21:35 <@matches> Even though we're supposed to be focusing on a literature review, I don't really like not having any code done yet
21:36 <@sulix> Yeah. I agree.
21:36 <@sulix> Code + fixing git stuff + preparing for this "talk" on Friday.
+--- Day changed Wed Mar 26 2014
+11:32 <@matches> I am in the super secret room
+11:36 <@sulix> Okay, I'll head in shortly. Had a small "parents fell for a scam email and entered passwords on dodgy websites" crisis here this morning.
+11:37 <@matches> Oh dear
+11:42 <@matches> The phone is ringing :O
+11:43 <@matches> Phew, it stopped
+22:42 <@matches> I think I have a way to do tests in the Makefile without using cmake
+22:42 <@matches> You can alter a variable for a target
+23:20 <@matches> Well, that ended badly
+23:21 <@matches> With me erasing my own Makefile using make
+23:21 <@matches> :P
+23:24 <@sulix> Better than erasing the source code, I guess.
+23:34 <@matches> This is why we have git
+--- Day changed Thu Mar 27 2014
+00:15 <@sulix> Crazy templated loading and saving!
+00:15 <@sulix> And now for bed!
+00:30 <@matches> Well
+00:30 <@matches> It doesn't break the test
+01:22 <@matches> We now have an arbitrary precision float
+01:22 <@matches> Where in this case arbitrary precision means I have no idea what the precision is but it is very bad
+01:35 <@matches> Ok I think I made a half precision float
+01:35 <@matches> They are quite bad
+01:36 <@matches> Um, I can probably make a graph of it being terrible as my contribution for Friday
+01:36 <@matches> Assuming I've done it right
+--- Day changed Wed Apr 02 2014
+09:41 <@matches> Dammit codejam is coming up again
+09:41 <@matches> There goes productivity
+09:42 <@matches> If you are not busy this afternoon we should do work
+09:42 <@matches> On the project I mean
+09:45 <@matches> Although it is tempting to just practice codejam problems for the next week
+12:44 <@matches> If I work on the project it will help when the inevitable "64 bits is not enough" problem comes up!
+12:45 <@matches> Maybe
+--- Day changed Sun Apr 06 2014
+13:40 <@matches> I get the feeling my part of the project could just be "typedef Real to something from boost"
+14:15 <@matches> I suppose I could talk about FPU and hardware
+--- Day changed Mon Apr 07 2014
+21:42 <@matches> I had a horrible horrible thought... implement a FPU in VHDL and then somehow run all our floating point operations on it :P
+21:42 <@matches> (This is not a good idea at all but it might be fun)
+21:42 <@matches> You know, for some definition of fun
+21:44 <@matches> So my lit review will probably be 1) We need higher precision documents because science (Pixels or Perish) 2) This is how FP works in hardware 3) This is how you can get higher precision in software
+21:45 <@matches> Oh, and 4) Document formats and rendering them (PDF/PostScript etc)
+21:46 <@matches> That is starting to sound suitably ridiculously broad?
+21:46 <@matches> Can always cut things out I guess
+21:47 <@matches> To reflect what we actually end up doing
+22:05 <@sulix> From what Tim was saying, I don't think "too broad" is a possibility.
+22:05 <@sulix> We could be talking about Aztec history and it'd probably not be "too broad."
+22:05 <@sulix> I do need to remember to read "Pixels of Perish," though.
+22:19 <@matches> I'll have a look into VHDL stuff, there seem to be compilers and simulators for linux
+22:20 <@matches> For a minute I was afraid I'd have to use the UWA EE VHDL environment
+22:20 <@matches> Which is like, running a Java program in a Windows XP VM
+22:20 <@matches> I heard you liked simulations of hardware so I simulated some hardware in your simulated hardware
+--- Day changed Tue Apr 08 2014
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+11:31 <@matches> The "Experiment Running" sign seems to have worked
+11:31 <@matches> Also open source VHDL stuff is less "actually compiles" than I had hoped
+11:32 <@matches> The two I've tried so far seem to generate absolute monstrosities of C or C++ files and then fail to compile and/or link
+--- Day changed Wed Apr 09 2014
+15:27 <@sulix> So I've been hitting my head against my desk for about half an hour trying to work out where some bugs were in some ipdf code I'm writing.
+15:27 <@sulix> Turns out to have mostly been precision issues due to the lack of precision in your Real data type.
+15:28 <@sulix> Switching it to double fixes them all.
+15:32 <@matches> Oh
+15:32 <@matches> Sorry
+15:37 <@sulix> Nah: it's good. It means that precision actually is important!
+15:37 <@sulix> (I was getting a little bit concerned for a while :P)
+15:40 <@matches> Well
+15:40 <@matches> I have rediscovered just how awful VHDL is
+15:41 <@matches> It seems like you can't define anything without typing it three times
+15:42 <@matches> You define an entity
+15:42 <@matches> Then you define a component with identical ports
+15:42 <@matches> Then you tell it to use the entity for that component
+15:42 <@matches> Then you tell it to map the identical ports to the entity ports
+15:42 <@matches> adder_0 : adder port map (a=>a, b=>b, cin=>cin, s=>s, cout=>cout);
+15:44 <@matches> Pretty much all the hardware papers I found talk about using VHDL for things
+15:46 <@matches> Let's see if I can make any sense of this jop-devel thing that appears to be a JVM implemented in VHDL
+15:47 <@matches> Uh oh, .bat files
+15:48 <@matches> This looks ominous
+15:51 <@sulix> The whole swapping out main thing breaks the makefile in a few ways btw.
+15:51 <@sulix> Because none of main.cpp's dependencies are listed.
+15:51 <@matches> Ah
+15:51 <@sulix> So if you change main.h, nothing gets recompiled.
+16:02 <@sulix> Okay, just pushed support for click+drag and zoom in and out in the viewer.
+16:03 <@sulix> (I did change the default precision to single, rather than half, as zoom out was totally broken with half-precision)
+16:05 <@matches> The half precision implementation is broken itself anyway
+16:07 <@matches> Hmm
+16:07 <@matches> I can't seem to compile anymore
+16:07 <@matches> Hang on
+16:07 <@matches> That would be because `uname -i` reports "unknown"
+16:12 <@matches> I have made unknown default to x86_64 :S
+16:13 <@matches> I can see the precision issues! Good work
+16:14 <@matches> These lecture notes seem useful: http://www.cs.berkeley.edu/~demmel/cs267/lecture21/lecture21.html
+16:14 <@matches> Lecture notes > Blog post in terms of suitable reference?
+16:16 <@sulix> It's got fortran in it, it must be suitably acedemic.
+16:18 <@matches> Haha
+16:18 <@matches> The VHDL compiler I am experimenting with uses Ada
+16:18 <@sulix> I'm getting my fill of new languages by trying out some c++11 features.
+16:20 <@sulix> I think I broak realtofloat by changing things to be single precision by default.
+16:22 <@sulix> (Hopefully fixed)
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+16:54 <@matches> What's with the netsplits
+16:55 <@matches> You're on mussel? I'm on mantis? They are VMs on the same host?
+16:55 <@matches> I don't know what this uniirc nonsense is
+16:56 <@matches> What is "arctic"
+16:56 -!- matches changed the topic of #ipdf to: Happy Bannana Netsplit
+17:33 <@matches> Well I compiled the VHDL FPU
+17:33 <@matches> It seems to work quite well
+17:33 <@matches> Except for the part where it never actually finishes an operation
+17:34 <@matches> One of the virtual transistors must have overheated
+17:43 <@matches> Oops it might help to actually give it a valid operation
+18:27 <@matches> Alright, so I'm going to experiment with getting our Real operations to run on the virtual FPU
+18:28 <@matches> Then I can look into both hardware and software ways of getting arbitrary precision.
+18:30 <@matches> VHDL appears to have text I/O so I could make everything read and write from pipes, but this seems like a terrible idea
+18:30 <@matches> On the other hand the compiler is using Ada
+19:21 <@matches> Oh wow
+19:21 <@matches> To open stdout
+19:22 <@matches> You pass it a string "STD_OUTPUT" for the filename
+21:40 <@matches> Ok, I give up trying to link this thing
+21:40 <@matches> fork() and exec() is seeming more and more elegant
+22:11 <@matches> Nooo, buffering
+22:11 <@matches> Ok, screw this
+--- Day changed Thu Apr 10 2014
+00:00 <@matches> Note: Actually exec'ing the program instead of just going straight to "exit(EXIT_FAILURE)" is generally important
+00:00 <@matches> Wall of text commit message incoming
+00:01 <@matches> Horribly inefficient interface to virtual FPU sort of implemented
+00:02 <@matches> I would have made it based on binary read/write rather than hex strings but I could not work out how to do that in VHDL
+00:08 <@matches> I still can't believe what I have just done, it seems ludicrous
+00:08 <@matches> Using an entire executable and stdio operations
+00:08 <@matches> To do a floating point addition
+00:10 <@matches> You should see how much is involved in compiling the VHDL FPU...
+00:11 <@matches> I'm very pleased that it actually compiled from the version in jop's github without much effort, but still
+00:11 <@matches> It's like 30 object files
+00:11 <@matches> This is why it isn't in the code repo
+00:19 <@matches> Whoops, there are some blatantly wrong comments in vfpu.cpp
+00:19 <@matches> Oh well
+--- Day changed Fri Apr 11 2014
+13:38 <@matches> Warning! I am about to make a ipdf/vfpu repo
+13:43 <@matches> You know what's really cool
+13:43 <@matches> You can run it as `vfpu --vcd=output.vcd`
+13:43 <@matches> And it will create a gtkwave file as it runs showing all the operations
+13:44 <@matches> You only get the simulated time from the point of view of the device
+13:44 <@matches> Which is probably useful
+13:46 <@matches> Or it would be if I wanted to compare different devices
+13:47 <@matches> To do that I need to actually make different devices...
+17:12 <@matches> Would you prefer seperate repos for the individual reports or just sub directories in the documents repo?
+17:12 <@matches> I can't decide
+17:12 <@matches> On the one hand 5+ repos is getting a bit out of hand
+17:12 <@matches> On the other hand they are individual work
+17:24 <@matches> Individual seems best
+20:31 <@matches> Hmm
+20:31 <@matches> The sqrt op in the fpu appears to have been commented out
+20:31 <@matches> Also despite having constants for the sizes of things they have just used magic numbers everywhere
+20:34 <@matches> I need an IRC script to prevent myself from saying stuff unless someone else has said things, or this channel will just be me ranting
+--- Day changed Mon Apr 14 2014
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+19:35 -!- ServerMode/#ipdf [+o sulix] by mussel.ucc.au.uniirc.com
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+19:57 <@13VAAAAGJ> Why am I now known as 13VAAAAGJ
+19:57 <@13VAAAAGJ> WHAT THE FUCK IS GOING ON
+19:57 <@13VAAAAGJ> ARE WE UNDER ATTACK
+19:57 <@13VAAAAGJ> Oh crap this is #ipdf
+19:57 <@13VAAAAGJ> Um, disregard this bit of the totally project related conversation
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+19:57 <@13VAAAAGJ> I'd edit the commit script to censor the swear words, but effort
+19:57 <@13VAAAAGJ> Oh dear
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+19:57 <@13VAAAAGJ> Hello
+19:58 <@13VAAAAGJ> I think mantis might be dying?
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+20:05 <@13VAAAAGJ> Sigh
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+--- Log closed Mon Apr 14 20:11:29 2014
+--- Log opened Mon Apr 14 20:18:05 2014
+20:18 -!- Irssi: #ipdf: Total of 2 nicks [1 ops, 0 halfops, 0 voices, 1 normal]
+20:18 -!- Irssi: Join to #ipdf was synced in 0 secs
+22:04 < matches> Ergh
+22:06 < matches> http://szmoore.net/ghdl.bug
+22:06 < matches> Pretty
+22:10 < matches> Looks like we'll be sticking with ASCII input files for the FPU
+--- Log closed Mon Apr 14 22:29:33 2014
+--- Log opened Mon Apr 14 22:44:34 2014
+22:44 -!- Irssi: #ipdf: Total of 1 nicks [1 ops, 0 halfops, 0 voices, 0 normal]
+22:44 -!- Irssi: Join to #ipdf was synced in 12 secs
+22:53 <@matches> Someone's VPS was compromised and killing our network
+22:53 <@matches> For reference
+22:53 <@matches> It affects this project because
+23:07 <@matches> Argh
+23:07 <@matches> So I thought I was being really clever
+23:07 <@matches> I had files of type "bit" and everything
+23:07 <@matches> Guess how a "bit" is represented...
+23:08 <@matches> It's an ASCII "0" or "1"
+23:09 <@matches> I guess I will just conclude that ASCII strings treated as hex is the only way
+--- Day changed Wed Apr 16 2014
+00:10 <@matches> I'm either about to perpetrate horrible things on your nice View class or give up and go to sleep
+00:28 <@matches> Yeah... the problem is if we want to overlay objects rendered using different precision's over each other
+00:28 <@matches> It leads towards templates
+00:29 <@matches> And templates lead towards fear
+00:29 <@matches> And fear leads towards anger
+00:29 <@matches> And anger leads to hate
+00:29 <@matches> I think
+00:29 <@matches> Saving an image
+00:29 <@matches> Recompiling the program
+00:29 <@matches> Overlaying the image
+00:29 <@matches> Is going to lead to less hate
+00:30 <@matches> Otherwise pretty much every occurance of "Real" needs to be come a template
+00:50 < sulix> So there are a couple of problems with doing that.
+00:51 < sulix> - You'd need some way of storing objects of different precision. Possibly an extra "high-precision bounds" struct.
+00:51 < sulix> - View also uses real for its internal bounds, which is where many of the problems appear.
+00:52 < sulix> (I guess you could have a "high-precision viewport" as well.)
+00:52 < sulix> - The actual upload of graphics data to OpenGL is done as 32-bit floats, no matter the type of real, as that's all OpenGL supports.
+00:53 < sulix> (At some point we'll have to actually do some view transforms on the CPU rather than just passing all of the bounds and viewport straight to OpenGL)
+01:02 <@matches> Yeah I don't want to replace Real with templates
+01:02 <@matches> That'd be horrible
+01:03 <@matches> By the way, the introduction of SDL_Renderer in SDL2 is confusing
+01:05 <@matches> I thought it was replacing Surface with Renderer and Texture
+01:05 <@matches> But Surface seems to still be a thing
+01:13 < sulix> Yeah: basically Surfaces are in CPU memory, textures in GPU memory.
+01:13 <@matches> Right
+01:14 <@matches> And renderers magically put stuff on surfaces/textures
+01:14 < sulix> Yeah.
+01:14 < sulix> So it basically represents the graphics card.
+01:15 < sulix> But if you want to just use OpenGL yourself, you don't need to create a renderer at all.
+01:15 <@matches> Ah, but the plot thickens
+01:15 <@matches> I'm saving the window to a bmp
+01:16 <@matches> Which requires a renderer
+01:16 < sulix> Hmm... I'm not sure if that will work.
+01:16 <@matches> It does
+01:16 <@matches> It seems rather convoluted though to be honest
+01:16 < sulix> (In theory, it shouldn't, but it probably actually does)
+01:16 <@matches> I seem to remember it not being this convoluted in SDL1.2
+01:16 <@matches> -_-
+01:16 <@matches> So the procedure is
+01:17 <@matches> 1. Get a surface associated with the window
+01:17 <@matches> 2. Allocate buffer of unsigned char for the pixels
+01:17 < sulix> Yeah, TBH I prefer SDL1.2's rendering API, but I generally just use OpenGL anyway.
+01:17 <@matches> 3. Get renderer from the window (NB: Don't use SDL_CreateRenderer, only the (undocumented) SDL_GetRenderer works because the Window already has a Renderer because it has been created with an OpenGL flag)...
+01:18 < sulix> In theory we should probably use glReadPixels.
+01:18 <@matches> 4. Use the magical renderer power to put pixels into the pixel array
+01:18 <@matches> 5. Create an RGB surface from the pixel array
+01:18 <@matches> 6. Now you can call SDL_SaveBMP, congratulations
+01:18 <@matches> What's this about a glReadPixels
+01:18 <@matches> I was just about to commit this
+01:19 < sulix> Well, you can use glReadPixels instead of steps 1,3 and 4.
+01:19 < sulix> (This is what SDL is doing behind the scenes)
+01:20 < sulix> Unfortunately, the SDL wiki is still down thanks to heartbleed. :/
+01:20 <@matches> :O
+01:20 <@matches> It was up when I looked at it before
+01:20 <@matches> Throwing python exceptions when I tried the search function though
+01:21 < sulix> Ryan said that it was up, but I'm still getting revoked certificate errors.
+01:22 <@matches> Hmm, I needed to do step 1 in order to know the size of the pixel array in step 2...
+01:23 < sulix> Screen::ViewportWidth(), Screen::ViewportHeight()
+01:26 <@matches> Yeah this is looking a lot shorter than what I had
+01:33 <@matches> It doesn't seem to work though
+01:35 <@matches> I'm getting a segfault
+01:35 <@matches> And of course valgrind automatically exits when it gets more than 1000000 errors from the flgrx driver
+01:38 <@matches> First call to glReadPixels is OK but the bmp is just white, second call segfaults
+01:39 < sulix> Hmm... what's the call?
+01:44 <@matches> Segfault was due to me forgetting about the pixels needing 4 bytes for RGBA
+01:44 <@matches> Still white though
+01:45 < sulix> (That was going to be my guess)
+01:45 <@matches> The advantage of getting the SDL_Surface
+01:45 <@matches> Was that you just pass all the surf->format->format->stuff
+01:45 <@matches> Everywhere
+01:45 <@matches> Also makes it rather verbose
+01:46 < sulix> The white screen might just be an fglrx bug.
+01:46 <@matches> There we go
+01:47 <@matches> No, it helps to remember that the pixels need 4 bytes for RGBA
+01:47 <@matches> I have very selective memory
+01:47 <@matches> I had to remember it for each line individually
+01:47 <@matches> Right I guess it is slightly nicer now
+01:47 <@matches> Although it has a bunch of magical "*4" everywhere
+01:48 <@matches> I'm going to put this on Stack overflow as an alternative to the answer I was originally following
+01:48 < sulix> Well, I'm going to attempt to sleep...
+01:48 <@matches> Thank you for fixing my bug without seeing it :S
+01:49 < sulix> I have far too much experience breaking glReadPixels...
+01:53 <@matches> We need an easy way to compare our document rendering the same thing using a different Real and/or view representation
+01:53 <@matches> Templates would only solve changing the Real and really they probably wouldn't actually solve it
+01:53 <@matches> They'd just create nightmares
+01:53 <@matches> Hmm
+01:55 <@matches> Um
+01:55 <@matches> Just looking at View::Render
+01:55 <@matches> Why is there a seperate loop for each type of object...
+01:56 <@matches> With "continue" statements for the other types in each loop
+01:56 <@matches> Is this so you can just make one call to glBegin and glEnd...
+01:56 <@matches> I am suitable scared
+01:57 <@matches> suitably scared and also suitable scared
+22:05 <@matches> Ok, trying again. This is the sort of thing a template is supposed to be used for... I just seem to always end up suddenly having to make everything all the way back to Document into a template class :S
+22:07 <@matches> blergh
+22:07 <@matches> trying again
+22:07 <@matches> After getting coffee
+22:07 <@matches> I think
+22:30 <@matches> Ok, templates is way too complicated
+22:30 <@matches> I am going to do the following instead:
+22:31 <@matches> 1. Allow a "save this region to bmp" argument
+22:31 <@matches> 2. It reads the specified bmp, saves a new bmp with the current view overlayed in a different colour or something
+22:32 <@matches> 3. Makefile hacks to recompile the program using a different typedef of Real and then do 1. and 2. for them all
+22:32 <@matches> 4. Realise I probably should have used templates
+23:02 <@matches> So, according to my timeline that I haven't looked at since submitting the proposal, I will have done a draft literature review by tomorrow...
+23:02 <@matches> Hah
+--- Day changed Thu Apr 17 2014
+00:26 <@matches> I am not good at OpenGL/SDL
+00:26 <@matches> I am the master of producing a black screen
+00:26 <@matches> Also we have FILLED and OUTLINE the wrong way round still
+14:01 < sulix> Bunch of bugfixes incoming.
+14:01 < sulix> I'm not proud of what I did to glReadPixels, but it works.
+14:02 <@matches> Uh oh
+14:02 <@matches> I just worked it out!
+14:03 <@matches> The dreaded merge begins
+14:03 <@matches> I'm tempted to just delete my changes and merge yours but I should probably do a real merge
+14:04 <@matches> I fixed it (on my machine at least) by: Using GL_BGRA instead of GL_RGBA (should probably detect which one to use from the screen's format)
+14:04 <@matches> And calling glReadBuffers and glPixelStorei before glReadPixels
+14:05 < sulix> glPixelStorei is probably nicer than what I'm doing.
+14:05 < sulix> I tried just giving SDL a negative pitch and a pointer to the bottom-right corner of the buffer, but somehow it didn't like that much.
+14:07 <@matches> You do actually check the byte order which is good
+14:08 <@matches> I worked that out but basically just changed it to match my machine :S
+14:08 < sulix> There are a bunch of endian problems in the load-save code anyway if we want it to run on big-endian machines.
+14:09 < sulix> (Well, big-endian documents don't load with little-endian code and vice-versa)
+14:10 <@matches> http://szmoore.net/ipdf/code/src/screen.cpp
+14:10 <@matches> Is the merge
+14:10 <@matches> Which one is better?
+14:11 < sulix> I think yours will still get the bitmaps upside down?
+14:11 <@matches> Ah yes they do tend to be upside down
+14:12 < sulix> I'm not sure you should need the front buffer stuff anymore with mine, so if you just keep mine (which is doing the flipping), everything should work.
+14:12 <@matches> Woah you fixed the FILLED vs OUTLINE
+14:12 < sulix> I did test overlaying bitmaps and it was fine.
+14:12 <@matches> Good
+14:12 <@matches> Does this seem like a better way to compare approaches than using a template and having View<float> View<double> etc?
+14:13 <@matches> It means recompiling
+14:13 <@matches> But it means a lot less templates
+14:13 <@matches> Pretty much the entire thing has to be templatified that way
+14:13 <@matches> And then there's the issue of what type the document is saving with
+14:13 < sulix> I think, long term, it'd be worth just extending the view to have a "bounds" and a "high_precision_bounds" or something.
+14:14 < sulix> But that is kind-of ugly.
+14:14 <@matches> I think it's probably nicer to just have real.h contain nothing but a typedef
+14:14 <@matches> And just recompile with a different typedef and overlay the images
+14:15 < sulix> Yeah, but there are some artefacts that really show better in motion, so it's probably worth supporting that at some point.
+14:15 <@matches> True
+14:15 <@matches> But including a video in the pdf will be difficult anyway
+14:16 < sulix> (Clearly, we should add embedded videos to ipdf)
+14:16 <@matches> You could also make a movie using ffmpeg
+14:16 <@matches> Haha
+14:16 < sulix> (I've got some OpenGL video playback code somewhere...)
+14:17 <@matches> In fact, if you can output a video you can just overlay two videos
+14:17 < sulix> Oh... my... god!
+14:17 <@matches> I don't know if there's a better way to make a video but I'd just be saving a .bmp every frame and then combine them all with fmpeg
+14:17 < sulix> Nope, that's probably a good way.
+14:18 < sulix> With some MAGIC it wouldn't even be slow.
+14:20 <@matches> Whoops your code isn't giving me a second bmp anymore
+14:20 <@matches> At least, not one that has pixels that aren't white
+14:20 <@matches> Does my glReadBuffer thing work for you?
+14:21 < sulix> Hmm...
+14:21 <@matches> Can fix the upside-downness some other way
+14:21 < sulix> Did you make clean
+14:21 < sulix> Because main.cpp/main.h won't recompile otherwise.
+14:21 < sulix> And I moved the glClear() calls.
+14:22 <@matches> I did make clean
+14:22 < sulix> Which is a less hacky way of solving the problem than reading the front buffer.
+14:23 <@matches> So the problem is that the texture rendered by Screen::RenderBMP isn't in the buffer that glReadPixels reads from?
+14:23 <@matches> (Even though it gets shown on the screen fine)
+14:25 < sulix> Hmm... it works fine here with or without glReadBuffers.
+14:27 < sulix> Try changing it to save the screenshot before calling scr.Present() in main.h
+14:29 <@matches> That works
+14:29 <@matches> But why?
+14:29 < sulix> Because when you call Present(), it allocates a new buffer to render into.
+14:30 <@matches> Right
+14:30 < sulix> This is so that you can start rendering the new frame immediately, rather than having to wait for the window manager to actually re-render the screen.
+14:31 <@matches> I have merged it
+14:33 < sulix> Excellent.
+14:33 < sulix> This is much more fun than literature!
+14:33 <@matches> :S
+14:35 <@matches> It's important
+14:35 <@matches> It's part of the timeline
+14:35 <@matches> Just you know
+14:35 <@matches> It comes after the Literature Review
+14:37 < sulix> Strictly speaking the Lit Review deadline is past, now, isn't it... :/
+14:38 <@matches> Well technically it was never a deadline for me... :P
+14:38 * sulix sighs
+14:38 < sulix> I'm special.
+14:39 <@matches> I need to read that last paper on FPUs more
+14:39 <@matches> It was talking about how there are all these software techniques from the 1960s that can actually be done on the FPU itself
+14:40 <@matches> I'll probably just work on getting our / jop's FPU working for different sized floats instead
+14:40 <@matches> In theory that will teach me how they actually work
+14:40 <@matches> Then I can actually understand the papers
+14:40 < sulix> But can you write about it in a Lit Review?
+14:42 <@matches> Maybe not so much the Lit Review, but it means I can write the Background section that explains how they work
+14:43 <@matches> There's probably some early papers on them that I can reference at the same time if I try hard enough to find them
+14:44 <@matches> The modern papers all have a lot of assumed knowledge
+15:59 <@matches> Instead of reading papers I have progressed towards compiling different types and then overlaying them
+16:02 <@matches> I didn't know you could do such cool things with Makefiles and flags to the compiler
+16:02 <@matches> If people knew more about this maybe we wouldn't have to have python
+16:03 <@matches> I will learn to do all my highlevel programming using Make
+19:48 <@matches> Our Render/Screenshot combo for overlaying bitmaps and $$$ only works the first time it is done
+19:49 <@matches> Or maybe it's RenderBMP that only works once
+19:49 <@matches> Hmm
+19:52 <@matches> I swear the format was BGRA earlier and now it's RGBA
+19:53 <@matches> This can probably get fixed after some Literature Review
+20:09 <@matches> Anyway you can now set the type of Real with `make DEF=-DREAL=X`
+20:09 <@matches> Or `make single` and `make double`
+20:09 <@matches> 0 and 1 respectively
+20:09 <@matches> I tried a little bit too hard to get it working with actual C strings
+21:32 <@matches> Minutes now have less "~*" in them
+21:32 <@matches> Wrong channel
+21:32 <@matches> Very wrong channel
+--- Day changed Mon Apr 21 2014
+12:32 <@matches> Literature Review O'Clock
+12:36 < sulix> I have just returned from my Easter holiday and have some horrible code for you to scream at while I have lunch. :P
+12:43 <@matches> Uh oh
+12:44 <@matches> stb_truetype ?
+12:44 <@matches> DejaVuSansMono.ttf ?!
+12:44 <@matches> Is this going to render a font...
+12:45 <@matches> Woah
+12:47 <@matches> Looks good
+12:48 <@matches> I think I will avoid looking at stb_truetype too closely...
+12:48 <@matches> Too late
+12:48 <@matches> Why are all the implementations in the .h file
+12:48 <@matches> And the .cpp file just has some defines...
+12:48 <@matches> shudder
+12:53 <@matches> I particularly like #define STBTT_assert(...) do {} while(0)
+12:53 < sulix> That's a standard way of doing that. SDL_assert does the same thing.
+12:54 < sulix> It lets you put a semicolon after it or use it in an if() statement without braces, etc, without things breaking horribly.
+12:56 <@matches> But... your assert doesn't actually assert anything?
+12:56 < sulix> That's because you generally only want it enabled in debug builds.
+12:56 <@matches> I guess
+12:57 < sulix> So typically you'd have it as do {} while(0) in release builds, and something like a function call in debug builds.
+12:57 <@matches> So what is this "more code" going to do :P
+12:57 < sulix> Slightly more modern opengl.
+12:58 <@matches> Yeah, that would be a good idea
+12:58 < sulix> In particular, uploading the content of a document to a VBO, and just re-rendering from that when needed.
+12:58 <@matches> Cool
+12:58 < sulix> Jumps from 9 fps -> 37 fps with 1024^2 objects.
+12:59 < sulix> I've been without internet, though, so it's pretty broken in many ways, still.
+12:59 < sulix> Like outline rects don't work.
+12:59 < sulix> And it still uses a bunch of OpenGL 1.0 stuff.
+12:59 < sulix> And for some reason the glPrimitiveRestartIndex() function isn't working.
+13:00 < sulix> Also I need to write shaders at some point, which will be work.
+13:00 <@matches> I just found the best comment in an IEEE email list
+13:00 <@matches> We should totally use it
+13:01 <@matches> "It is too late now to repair the mistakes of the past that are present in millions of installed systems, but it is good to know that careful research before designing hardware can be helpful"
+13:01 < sulix> Oh man, that's basically the thesis in one sentance.
+13:02 <@matches> Dibs!
+13:02 <@matches> Although I doubt anyone will care if we both quote it
+13:03 < sulix> One thing I did discover reading my OpenGL book is that I think we can get OpenGL to use doubles with some shader hackery.
+13:03 <@matches> :O
+13:03 < sulix> Then again, the book was (partly) written by (one of) the authors of fglrx, so take it with the requisite salt.
+13:04 <@matches> Ah, so how many goats were required?
+13:05 < sulix> Just the two, I think.
+13:06 <@matches> This email message seems sort of vaguely relevant? It's the "infamous double rounding problem"
+13:06 < sulix> I take it that you worked out how to swap between CPU and GPU transforms with right-click.
+13:07 <@matches> I read it in the commit message
+13:08 < sulix> I was quite happy with how much nicer things ran with CPU transforms and doubles.
+13:08 <@matches> I think I can see a difference zooming in far enough
+13:08 <@matches> Yeah that's a huge difference
+13:08 <@matches> I had a tester that was going to automatically make images of the difference when you zoomed in really far
+13:09 <@matches> But there were issues with the screen shot / bmp rendering
+13:09 <@matches> Probably the bmp rendering
+13:09 < sulix> .bmp files suck.
+13:10 <@matches> They are nice and simple though?
+13:10 <@matches> At least, the SDL API is nice and simple
+13:10 < sulix> That's more a triumph of SDL than of the .bmp file format.
+13:10 <@matches> After looking through gm6 files with a hex editor to try and extract sprites...
+13:11 <@matches> Well we could always just fwrite the pixel buffer and fread it back
+13:11 <@matches> If you want no one to be able to use our files without compiling our program :P
+13:12 < sulix> I'm personally a fan of LodePNG, but I'm too lazy to hack it in at the moment: http://lodev.org/lodepng/
+13:13 < sulix> I'm probably going to get around to fixing all of the warnings in stb_truetype one day.
+13:13 <@matches> Haha
+13:13 <@matches> What about implementing an Oct-tree?
+13:14 <@matches> So .bmp is just a header and then the raw pixel data? What's disgusting about that? No compression?
+13:16 <@matches> Wait png is also just a header and then an IDAT section
+13:17 <@matches> Oh well you can put lodepng in if you want I guess
+13:17 <@matches> As long as I can open the images in eom
+13:18 <@matches> Ah so PNG is compressed. I missed that
+13:19 <@matches> Meh
+13:19 <@matches> Oh and alpha channel
+13:19 <@matches> Yeah
+13:19 <@matches> I remember that now
+13:20 <@matches> xpaint is the least shitty of the shitty sprite editors in debian, but it only stores RGB because it was designed around bmp and I guess they just hacked on exporting to other formats later
+13:21 <@matches> If you open things with alpha it gets really confused
+13:23 < sulix> You can put alpha in .bmp files, but then they sometimes crash KDE.
+13:26 <@matches> We can just run all our bmp files through image magick
+13:26 <@matches> convert a.bmp a.png
+13:26 <@matches> Done
+13:27 <@matches> Hmm, maybe if I opened the data from the gm6 files as png they would work, I was assuming they were bmps -_-
+13:27 <@matches> Actually gif
+13:27 <@matches> Probably
+13:28 <@matches> Since it has "Save as gif"
+13:28 <@matches> But that is not relevant to this project
+13:33 < sulix> Damn, just discovered that the opengl feature I was using for rectangle outlines is not supported by my laptop's hardware.
+13:34 < sulix> (This explains one of the bugs I've been seeing, but sadly only one)
+13:47 < sulix> Okay, remaining code pushed.
+13:47 < sulix> I am sorry.
+13:53 <@matches> I'm messing around trying to do something evil so I'll merge later
+13:53 <@matches> But you don't seem to call ToggleGPUTransform when there is a right click
+13:54 <@matches> Oh wait, I need to make clean
+13:54 <@matches> Cool
+13:54 <@matches> (So much for our Makefile magically tracking the header files :S)
+13:58 < sulix> It does it for every header file except ones included by main.cpp because of the weird main.cpp swapping stuff.
+13:59 <@matches> That main swapping stuff is amazing
+13:59 <@matches> It is worth it
+13:59 <@matches> Except main.cpp ends up eventually including all the header files
+14:00 <@matches> I think there is an alternative Makefile that just has every single header file in the current directory as a dependency for each .o file
+14:01 <@matches> But I'm normally used to running make clean anyway
+14:22 <@matches> Eh I was going to make a video of the difference between GPU and CPU coord transforms but it's not that great
+14:23 <@matches> Whatever you have done does not look happy
+14:24 < sulix> It takes like 5 minutes to DebugDumpObjects with a million objects, but it works okay* after that.
+14:24 <@matches> Yeah ok
+14:24 < sulix> *well, sort-of.
+14:25 < sulix> If you just want to show off the precision, getting rid of most of those objects is probably the right thing to do.
+14:25 <@matches> Interesting things happen when you zoom out really far
+14:25 <@matches> Do we care about that
+14:25 < sulix> I'm going to go with "no".
+14:26 <@matches> Ah, but the rectangles are not all the same size
+14:26 < sulix> This is a product of rounding to the nearest pixel. They'd be fine with antialiasing.
+14:29 <@matches> I have pushed a single line contribution
+14:29 <@matches> I decided not to bother with all the changes I made to make the video prettier
+14:29 <@matches> Since I can't actually capture my desktop properly anyway
+14:30 <@matches> I suppose I could make it render bmps and ffmpeg them all but that is way too much effort
+14:31 <@matches> So
+14:31 <@matches> Literature Reviews
+14:31 <@matches> They are a thing
+14:38 <@matches> I probably should not reference an email thread
+14:53 <@matches> In other news, I think this jvm FPU doesn't actually implement sqrt
+14:57 <@matches> It always gives 0x0 on sqrt ops
+14:57 <@matches> I certainly hope there isn't a jvm somewhere that just doesn't do square roots
+14:58 <@matches> They probably hacked it into some other part of their project instead of putting it in the FPU
+16:08 <@matches> So fprintf style formatting isn't very clever when it comes to floats vs doubles vs long doubles
+16:11 <@matches> Eg: %lf will work for either floats or doubles and %f will work for either floats or doubles (by truncating) but %llf is the only thing that works for long doubles and it only works for long doubles
+16:12 <@matches> s/truncating/casting whatever
+16:52 <@matches> We can compile with long double
+16:52 <@matches> I suspect this may break things but whatever
+16:52 <@matches> Running calculatepi on motsugo to see how much difference it actually makes...
+17:08 <@matches> Charles Babbage seems like an interesting fellow
+17:09 <@matches> "e sought to prove the
+17:09 <@matches> reality of the devil by drawing with his blood a
+17:09 <@matches> circle on the floor and repeating the Lord’s prayer
+17:09 <@matches> backward"
+17:09 <@matches> The things one does for science
+17:44 <@matches> Reading about Charles Babbage counts as Literature Review...
+17:44 <@matches> Actually I'm trying to find a paper written *by* him
+17:44 <@matches> Since apparently he came up with Floating Point representations
+22:11 <@matches> Found an actual paper talking about floating points on GPUs
+22:12 <@matches> It says they don't conform to IEEE and also the manufacturers don't like to tell people what they do do
+22:12 <@matches> So they wrote a version of Paranoia, which was a test program for computers in the 1980s before IEEE, to work out the characteristics of flops on various GPUs
+22:13 <@matches> This is probably of interest
+22:14 <@matches> So far one of the best papers I have on algorithms in software is actually one talking about implementing those algorithms in hardware instead
+22:15 <@matches> I also have a random obituary to Charles Babbage just because
+22:16 <@matches> Unfortunately UWA directs me to some useless website that just tells me the citation details and doesn't give me a download for any of Babbage's papers
+22:17 <@matches> He has some books but they are mostly about economics
+22:18 <@matches> Would have been nice if he'd written something that says "I have invented floating point" but I guess not
+22:18 <@matches> That's only really of historical interest but it'd be nice
+--- Day changed Tue Apr 22 2014
+01:17 <@matches> Urgh looking at the git diff
+01:17 <@matches> I really have not accomplished much
+01:30 <@matches> Oooh, motsugo finally got to a number of intervals where long double is better than double
+11:56 < sulix> So it turns out that I've broken the open-source GL drivers.
+11:56 < sulix> They don't support one of the features ("primitive restart") we need when in compatibility mode.
+11:56 < sulix> So I guess now I've got to rewrite everything to use OpenGL 3.
+14:47 <@matches> ?
+14:48 <@matches> I should probably look more carefully at what the OpenGL stuff is doing nowdays
+14:49 <@matches> Downgrading to OpenGL 3 sounds drastic
+14:50 <@matches> Wait 3 is the OK one, 4 is the new one
+14:50 <@matches> 1 is the ancient one
+14:52 <@matches> I see pointer arithmetic...
+14:53 <@matches> banana would be furious
+14:53 <@matches> should be using std::super_ptr_unsegfaultable_arith
+14:53 <@matches> (I am not a fan of the smart pointers)
+14:55 <@matches> *indexData = 0xFFFFFFFF; // Primitive restart.
+14:55 <@matches> I do not know what is going on here :S
+14:58 <@matches> Ahh I get it now
+14:58 <@matches> Reading commit messages turns out to be useful
+15:04 <@matches> git blame for view.cpp reveals that I still own the opening braces on some things
+15:05 <@matches> That's about it :P
+15:06 <@matches> I'm going to keep looking at rounding errors and maybe have a better thing than calculating pi
+15:06 <@matches> As a bench mark
+15:07 <@matches> I might look at Paranoia
+15:07 <@matches> Although it was originally in BASIC
+15:07 <@matches> And ~7000 lines
+15:07 <@matches> With almost no whitespace characters
+15:07 <@matches> And totally no indents
+15:08 <@matches> I sometimes get the feeling people used to be smarter than we are now...
+15:08 <@matches> Then I remember that those people are ultimately responsible for the tools we use now
+15:15 < sulix> Speaking of tools we use now, I think I've just got the debug font code to not only randomly corrupt a varible, but also cause valgrind to crash.
+15:18 < sulix> Okay, we need to fix that makefile at some point.
+15:38 <@matches> make clean?
+15:41 <@matches> It's not actually swapping out main.cpp
+15:41 <@matches> It just doesn't have main.o in the link objects and has main in the $(BIN) target and the testers in the tests/% target
+15:42 <@matches> I guess that is swapping out main but MAIN is not being changed
+15:42 <@matches> derp
+15:45 <@matches> I think I fixed it?
+15:45 < sulix> Ah. Well, you've got a merge conflict to look forward to.
+15:45 <@matches> Not if I just NEVER COMMIT IT
+15:46 <@matches> I'm going to call your fix being right and mine being a horrible hack
+15:46 <@matches> Ok I pullsd some changes to graphics stuff, is that it or is there more?
+15:46 < sulix> I haven't fixed it, I've just gone and bu(gg|ff)ered up the font stuff.
+15:47 <@matches> So it's not meant to render unless something changes? But the debug font stuff is changing so it needs to keep rendering?
+15:48 <@matches> I see a lot of "Flushing Debug Font arrays"
+15:48 < sulix> The debug font stuff is separate from the whole view system.
+15:48 <@matches> That makes sense
+15:48 < sulix> It's just trying to fill up a buffer of quads with individual characters in it and then draws them when the buffer gets full.
+15:49 < sulix> One more step on the path of getting rid of all of the OpenGL 1.1 stuff.
+15:50 <@matches> Haha
+15:50 <@matches> git stash seems to think I modified graphicsbuffer.h and screen.h
+15:51 <@matches> git diff seems to think everything is identical
+15:51 <@matches> I'm just going to git reset the things I didn't actually change...
+15:52 < sulix> I do that far too often.
+15:52 <@matches> Oh there is a comment "//test" for testing the Makefile
+15:53 <@matches> And a comment "This isn't the Screen class?" where you copy/pasted the screen class description for the GraphicsBuffer class
+15:53 <@matches> I don't think they need to be preserved
+15:54 < sulix> Yeah, I should have got rid of that screen class bit by now.
+15:55 <@matches> Have a 2 line commit
+15:55 < sulix> The best kind.
+15:55 <@matches> I really need to cut back on the new line creep
+15:56 <@matches> It's like I can't add a line by itself without putting in extra whitespace
+15:57 <@matches> Uh oh we've ran out of coffee here
+15:58 <@matches> I'm slightly scared by how much the graphics code has increased since I last actually understood how it worked...
+15:59 <@matches> Can you change those *vertexData to *(vertexData++) or is that considered even uglier
+16:03 < sulix> I thought of that, but given how much pointer arithmetic debugging I was going to do, I wanted it to be really obvious when the pointer was being incremented.
+16:03 < sulix> The plan is to have a nice AppendFloat() function or similar that will do this eventually.
+16:05 < sulix> Hmm: "Buffer usage warning: Analysis of buffer object 2 (bound to GL_ARRAY_BUFFER_ARB) usage indicates that the GPU is the primary producer and consumer of data for this buffer object. The usage hint supplied with this buffer object, GL_STATIC_DRAW, is inconsistent with this usage pattern. Try using GL_STREAM_COPY_ARB, GL_STATIC_COPY_ARB or GL_DYNAMIC_COPY_ARB instead.
+16:06 < sulix> Thanks nVidia.
+16:06 < sulix> Now if only we were using OpenGL 4.4 which got rid of buffer usage hints entirely.
+16:29 <@matches> Also I think you forgot the naming scheme :P
+16:30 <@matches> vertex_data
+16:31 <@matches> I will go back to pretending to be doing a literature review
+16:32 <@matches> Instead I will probably plot some graphs
+16:48 <@matches> So
+16:48 <@matches> If you look up "Handbook of Floating Point Arithmetic" on google (which lots of things like to reference these days)
+16:48 <@matches> You can download the entire thing
+16:48 <@matches> I was prepared to pay like $20 for it on amazon
+16:49 <@matches> Oh amazon doesn't sell actual books anymore though does it?
+16:49 <@matches> No they do have it
+16:50 <@matches> For $100...
+16:50 <@matches> I think I'll just stick with my free pdf thanks
+16:55 <@matches> "Handbook" being 579 pages...
+17:04 <@matches> I think if a textbook is citing blog posts we can probably get away with it
+17:05 <@matches> Oh my god I love this textbook
+17:05 < sulix> I was watching a conference talk last night when the presenter just said: "this technique is described on this guys blog. Here's a link."
+17:05 <@matches> "Table 1.1 gives the results obtained by compiling Program 1.1 and running on a Pentium4, using the GNU Compiler Collection and the Linux system"
+17:06 <@matches> [Complete C code for Program 1.1 follows]
+17:06 <@matches> None of this "Pseudo code" crap
+17:07 < sulix> Clearly we should get an extra 10% for every line of pointer arithmetic in our theses.
+17:07 <@matches> There'
+17:07 <@matches> s a problem here
+17:07 <@matches> How do I not make the entire literature review just paraphrased from this one text book
+17:08 <@matches> Mr Gullible and the Chaotic Bank Society!
+17:08 <@matches> It has stories!
+17:08 <@matches> Parents should read this textbook to their children
+17:09 < sulix> I'm pretty certain I know someone with a data structures and algorithms picture book...
+17:09 <@matches> That reminds me of a children's book I wrote about multithreading
+17:10 <@matches> I should probably scan it one day
+17:10 < sulix> Did it begin "Once upa timeon...
+17:10 <@matches> I think it did actually
+17:10 <@matches> Once upon a time there was a process who had a lot of work to do...
+17:11 <@matches> "I should probably scan it one day" - Why not TODAY!
+17:11 * matches goes searching
+17:16 <@matches> It is no where to be found
+17:16 <@matches> I distinctly remember going to throw it out and deciding not to, but not where it actually went
+17:27 <@matches> So maybe compiling a bunch of HFPA's examples using our Real type is a good way to make benchmarks
+17:27 <@matches> I don't know
+17:27 <@matches> My part of the project seems to move further and further away from the document formats thing
+17:27 <@matches> Maybe I'll try and compile the GPU Paranoia
+17:28 <@matches> Hah
+17:34 <@matches> It seems like whatever Mathematica does is what we should do
+17:35 <@matches> I wonder if wolfram is open about how Mathematica actually works
+17:35 <@matches> I don't think they are
+17:35 <@matches> The CQM lecturer for physics found a bug in Mathematica's number representation once that she showed us
+17:35 <@matches> Apparently she reported it years ago and it's still there
+17:36 <@matches> This segued nicely into why we should learn fortran
+--- Day changed Wed Apr 23 2014
+14:00 <@matches> IEEE's float encoding is inconvenient
+14:01 <@matches> The mantissa is like, reversed
+14:01 <@matches> b_{23-i} * 2^{-i}
+14:19 <@matches> And the implicit extra 1 except when it isn't is a pain in the ass as well
+14:19 <@matches> It's like
+14:19 <@matches> I can't just copy the right bits I have to think
+14:19 <@matches> What is this
+14:19 <@matches> Mental effort
+14:19 <@matches> Blargh
+14:20 <@matches> I should have just stuck with the 8 bit floats with their 2 sign bits
+14:20 <@matches> The hydra float
+15:17 <@matches> Wow you get really different representations with an IEEE encoding of the bits
+15:17 <@matches> ...
+15:17 <@matches> I think I liked just treating the two parts as integers in the order they were stored better
+15:18 <@matches> I have to call pow(3) and a floating point division for every '1' in the mantissa to get it to agree with IEEE
+15:19 <@matches> Unless I'm missing some obvious trick
+15:20 <@matches> But in IEEE the mantissa is not an integer
+15:37 <@matches> Ooookkk
+15:38 <@matches> You're precision doesn't disappear as fast when you do it that way
+15:38 <@matches> Your
+15:38 <@matches> Whatever
+--- Day changed Thu Apr 24 2014
+14:40 -!- You're now known as notmatches
+14:40 -!- You're now known as matches
+14:41 <@matches> Ok, less spammy channel time
+14:41 -!- mode/#ipdf [+b m:matches!*@*] by matches
+14:41 <@matches> Spam
+14:41 <@matches> Dammit
+14:42 -!- mode/#ipdf [-o matches] by matches
+14:42 < matches> Spam
+14:43 < matches> Yay
+14:43 < matches> ... this will all appear in the next git commit won't it -_-
+14:52 -!- You're now known as notmatches
+14:52 -!- You're now known as matches
+--- Day changed Sat Apr 26 2014
+00:45 -!- mode/#ipdf [+o matches] by OperServ
+00:46 <@matches> Incoming "at least it is self consistent in its wrongness" floating point conversion
+00:48 -!- mode/#ipdf [-o matches] by matches
+00:48 < matches> Still can't talk
+00:48 < matches> Excellent
+--- Day changed Sun Apr 27 2014
+17:10 < sulix> I finally got ipdf working on my laptop again by porting everything to OpenGL 3.1.
+17:10 < sulix> I'm so sorry about how ugly the code now is, by the way.
+18:04 -!- mode/#ipdf [+o matches] by OperServ
+18:05 < Pommers> You know what a really good feature for a PDF reader would be? The ability to have it completely borderless without menus, so you just see the page!
+18:06 <@matches> Wat
+18:06 <@matches> Well we've got that
+18:06 <@matches> We just can't read pdfs
+18:07 <@matches> Did you get much done not going to the cleanup?
+18:07 <@matches> I managed to transfer some dust from one location to another location, and then the wind blew it back in my face
+18:08 <@matches> Then I looked at Frames' proposal and despaired at how much it is actually complete and has words in it
+18:08 <@matches> I think he's onto something with his plan of actually writing things
+18:14 -!- matches changed the topic of #ipdf to: ipdf the pdf doesn't stand for pdf
+18:14 -!- matches changed the topic of #ipdf to: ipdf the pdf doesn't stand for pdf but the df stands for df
+18:14 -!- matches changed the topic of #ipdf to: Sort of
+18:15 <@matches> I need a script to auto mute me...
+18:15 < sulix> I spent basically all of today on that one commit.
+18:15 -!- mode/#ipdf [-o matches] by matches
+18:15 -!- mode/#ipdf [+o matches] by OperServ
+18:15 < sulix> Whether or not that was more useful than the cleanup remains to be seen.
+18:16 <@matches> I should look at it I guess :P
+18:16 < sulix> It compiles*
+18:16 < sulix> *but has lots of warnings.
+18:16 <@matches> It can't be worse than my tester that converts floats to floats
+18:17 < sulix> I'm pretty certain it can be and is worse.
+18:17 <@matches> However I've realised I kind of actually do need to be able to do that
+18:17 <@matches> Woah 3k+ lines
+18:17 <@matches> * 4k+ lines
+18:18 < sulix> Most of it was autogenerated, but still...
+18:18 * matches weeps for OpenGL 1
+18:18 < sulix> You don't realise how much you miss it until it's gone...
+18:19 <@matches> So what does all this stuff actually do
+18:19 <@matches> Because I could see rectangles and things just fine without it
+18:19 < sulix> Exactly the same thing as before but it works on my laptop now.
+18:19 <@matches> I see a shader program, that's obviously good
+18:20 <@matches> Actually I see code for a shader but no shader yet
+18:20 < sulix> The shaders are all #defines, I'm afraid.
+18:22 <@matches> What was wrong with your laptop?
+18:23 < sulix> It doesn't support the OpenGL compatibility mode, so --- as I was using the OpenGL 3.1 feature of "primitive restart", I had to code the entire thing in OpenGL 3.1
+18:23 < sulix> On the bright side, this paves the way for doing things like getting the GPU to use doubles.
+18:26 <@matches> Ooh
+18:27 < sulix> (also halves)
+18:27 < sulix> (halfs?)
+18:27 <@matches> Do GPUs use IEEE floats? I had a reference that seemed to be complaining they didn't
+18:27 <@matches> Although it was circa 2007
+18:28 < sulix> I don't think that there's a requirement that they internally use them, but they do read and write them.
+18:28 < sulix> A bit like how x86 processors use(d) 80 bit reals internally and rounded when reading/writing to memory.
+18:28 <@matches> Do halves have a different mantissa encoding
+18:29 <@matches> The examples given on wikipedia seem wrong
+18:30 < sulix> I think this is the canonical description: http://www.opengl.org/registry/specs/NV/half_float.txt
+18:33 <@matches> That would be before IEEE specified half (binary16) but its the same summation for the mantissa anyway
+18:33 <@matches> binary16 is (briefly) in the 2008 revised 754
+18:34 <@matches> So I think wikipedia is giving a wrong example, but I'm not confident enough to go and change wikipedia
+18:35 <@matches> Also I just realised my conversion of the mantissa to a Real is horrible
+18:35 <@matches> Oh well, it can get fixed later
+18:36 <@matches> Hopefully I can finish my fluid mechanics assignment quick enough to actually work on my progress report / proposal / thing
+18:36 <@matches> (Hah)
+18:36 -!- mode/#ipdf [-o matches] by matches
+18:37 < sulix> Yeah, I'm going to see how much Lit review I can write for tomorrow. :/
+--- Day changed Mon Apr 28 2014
+22:06 -!- mode/#ipdf [+o matches] by OperServ
+22:10 <@matches> Must find motivation to work on Lit Review at 10pm...
+--- Day changed Tue Apr 29 2014
+10:06 <@matches> Must find motivation to work on Lit Review at 10am...
+--- Day changed Wed Apr 30 2014
+13:04 <@matches> I wanted to rasterise a vector image so I could compare them at the same scale ("These look the same!") and zoomed ("This one looks crappier!)
+13:04 <@matches> But because vector graphics editor/viewers don't use pixels as units but they do when they export to a bitmap, it's difficult to actually get them to look the same
+13:04 <@matches> Before scaling
+13:05 <@matches> I guess a screenshot tool might be the best way
+13:06 <@matches> I don't know if I need to do this really
+13:07 <@matches> I guess Mechanical and Chemical engineers marking this will probably benefit from having an example
+13:07 <@matches> Doesn't everyone know the difference between vector and raster graphics
+13:07 <@matches> Where was that paper that had tux vector and rasterised
+13:10 <@matches> Ah, worth2003xr.pdf
+13:11 <@matches> If it's in a paper I guess it can go in a Lit Review
+13:11 <@matches> At least until I have something better
+13:15 <@matches> Kind of ironic that the image I am using was actually scanned first as a bitmap and then converted to vector using Trace Bitmap
+13:57 <@matches> Ah, it's actually impossible to get it to be exactly the same, because even taking a screenshot on my own screen it will then be different depending on the display of whoever reads the digital pdf
+13:57 <@matches> Oh well
+13:58 <@matches> I suppose "It looks shittier" will have to suffice without trying to make them look exactly the same before scaling
+13:59 <@matches> I have spent WAY too long making this example
+13:59 <@matches> I could have just gone "See \cite{worth2003xr.pdf}"
+16:00 <@matches> So it might be worth talking about dpi in pdf viewers and how it SUCKS
+20:17 -!- mode/#ipdf [-o matches] by matches
+21:14 -!- mode/#ipdf [+o matches] by OperServ
+21:46 <@matches> I have perpetrated XML on the codebase
+21:47 <@matches> I have grand visions of our code supporting SVGs
+21:47 <@matches> I also have grand visions of actually doing a Literature Review
+21:50 * sulix git pull's with some trepidation.
+21:52 < sulix> Never heard of pugixml before but it looks okay.
+21:55 <@matches> The W3C XML specification is pretty terrifying
+21:56 <@matches> I will feel more like I've satisfied the "Document Formats" part of the Literature Review if I say some things about it
+21:57 <@matches> Well SVG in particular
+21:57 <@matches> SVG defines a "minimum" precision of IEEE binary32
+21:58 <@matches> But there's a specification for "High Quality" viewers that have to use binary64
+21:58 <@matches> That's probably the only real thing relevant directly to our problem
+--- Day changed Thu May 01 2014
+01:23 <@matches> It's May 1st
+01:23 <@matches> This means we can no longer say "The Literature Review is due Next Month"
+01:23 <@matches> IT'S DUE THIS MONTH
+01:23 * matches freaks out
+01:23 <@matches> ... but after sleep
+01:25 <@matches> Page 12 of my Literature Review by the way
+01:25 <@matches> Is the only page I like
+16:34 <@matches> The C version of paranoia compiled for me
+16:34 <@matches> Not terribly exciting (I have an IEEE 754 compatible processor! Amazing)
+22:17 <@matches> W Kahan's website is a very interesting if slightly difficult read
+22:24 <@matches> He appears to have written this 80 page pdf in a day
+22:27 <@matches> It kind of reads like one of those religious propaganda pamphlets
+22:27 <@matches> "Java is the Work of Satan"
+22:27 <@matches> "Kernighan-Ritcie C floating-point semantics are the light"
+22:28 <@matches> But every so often he has a graph or example that makes him seem less crazy
+22:34 <@matches> "And now Java forbits you to mention or use extra-precise long double arithmetic, though IEEE Standard 754 recommends its use and over 95% of computers on desktops have it built into their hardware. You paid for it, but Java denies you its benefits."
+22:34 <@matches> Java has long double now right?
+22:34 <@matches> Although that JOP I was looking at was just 32 bit
+22:36 <@matches> Ah, java.lang.math.BigDecimal
+22:37 <@matches> "But be careful with division, because it will throw exceptions if it's like 1/3, then it will be Non-terminating decimal expansion."
+22:37 <@matches> That sounds horrifying
+22:40 -!- mode/#ipdf [-o matches] by matches
+--- Day changed Sat May 03 2014
+22:01 < sulix> My crazy idea to you would be to research p-adic number representations.
+22:01 < sulix> It's been a while, but they were mentioned a couple of times in pure maths units and seemed interesting/crazy and I can't remember much about them.
+22:28 -!- mode/#ipdf [+o matches] by OperServ
+22:29 <@matches> I will look at them, the "just use a float but with more bits until you run out of memory" doesn't seem a very well thought out approach
+22:29 <@matches> Maybe someone actually cares enough to research better ways
+22:29 <@matches> I mean, something's wrong with an idea when you can write "1/3" and have a runtime exception (re: Java BigNumber)
+22:30 <@matches> I plan to write some nasty things about Java based on Kahan's rants so as to gloss over the fact that it has BigNumber built into it and forstall the inevitable "Why didn't you use Java!"
+22:31 < sulix> I think we want to truncate to whatever the most accurate you can see at the given zoom level.
+22:31 <@matches> Yeah
+22:32 <@matches> It annoys me that XML and HTML specs don't have a PDF version
+22:32 < sulix> I've been printing to pdf for some of those things.
+22:33 <@matches> None of the links to different sections would work though
+22:35 <@matches> Specifications are thrilling
+22:35 <@matches> "How to read this specification"
+22:35 <@matches> "This specification should be read like all other specifications"
+22:35 <@matches> Oh wait
+22:35 <@matches> It actually gets better
+22:35 <@matches> Is that...
+22:35 <@matches> Humour!
+22:36 <@matches> I thought that wasn't allowed!
+22:36 <@matches> "First it should be read cover-to-cover, multiple times. Then, it should be read backwards at least once. Then it should be read by picking random sections from the contents list and following all the cross references"
+22:37 <@matches> As much as I love the idea of reading 626 pages of specification backwards...
+--- Day changed Tue May 06 2014
+00:39 <@matches> http://szmoore.net/ipdf/sam/rate-my-litreview.py
+00:39 <@matches> Tim will be thrilled!
+00:40 <@matches> I'm probably going to really regret making that
+00:41 <@matches> The regret is rising to the surface
+00:41 <@matches> It's an example of an interactive document format
+00:41 <@matches> The pixels or perish guy would approve
+00:43 <@matches> So much regret
+00:43 -!- mode/#ipdf [-o matches] by matches
+23:37 -!- mode/#ipdf [+o matches] by OperServ
+23:38 <@matches> So, I have this book called "Computer Graphics" that is pretty amazing
+23:38 <@matches> Funnily enough it has all the algorithms in it
+23:38 <@matches> For computer graphics
+23:38 <@matches> Probably should have been reading it ages ago but I thought we were worrying more about precision
+23:38 <@matches> I don't even know anymore
+23:39 <@matches> Have to read 500pg textbook on graphics, 500pg textbook on floating point numbers, 500pg PDF/PostScript standards...
+23:39 <@matches> Too many pages
+23:39 <@matches> Anyway it has a section on Octrees
+23:39 <@matches> But don't worry
+23:39 <@matches> It mentions Quad trees
+23:39 <@matches> It also actually mentions fractals
+23:39 <@matches> As a thing
+23:40 <@matches> In other news, extending the document we have at the moment to allow anything other than rectangles will be interesting
+23:41 <@matches> Did you do this on purpose? :P
+--- Day changed Wed May 07 2014
+12:32 <@matches> We need to do something about all the warnings generated by the magic OpenGL 3 stuff
+12:32 <@matches> It's making it hard to sport warnings that I actually care about
+12:33 <@matches> Like: You forgot to return a value in this function :S
+13:52 <@matches> Gah I did it again
+13:52 <@matches> auto is dangerous
+13:53 <@matches> Possibly because it's buggy
+13:53 <@matches> I can't actually see any compiler warnings at all
+17:39 <@matches> So you can almost maybe see a difference between beziers calculated using floats and doubles
+17:40 <@matches> If you squint
+17:40 <@matches> And view them on different monitors
+17:41 <@matches> Ah there we go
+17:41 <@matches> I successfully broke it
+17:42 <@matches> When you round to pixel positions it doesn't make a difference
+17:43 <@matches> But on the other hand if you calculate beziers using really big numbers they look wierd :P
+17:43 <@matches> That's important
+17:43 <@matches> Because if you have an arbitrary infinite document you might be at coordinate positions that are really big
+17:43 <@matches> Captain Obvious strikes again
+17:45 <@matches> I think I will make a video of a circle moving towards infinity
+17:45 <@matches> This probably won't help the literature view much but it's too tempting to resist
+17:46 <@matches> I gave up trying to deal with our document format so I currently just generate vector<pair<T, T> > and then map that to a bitmap :P
+--- Day changed Thu May 08 2014
+10:57 <@matches> So circle was a terrible example
+10:57 <@matches> It stays as a circle
+10:58 <@matches> Hopefully the first curve I tried wasn't just a bug
+12:31 <@matches> I think it was a bug
+13:35 <@matches> There are bezier things in ipdf/code/src/tests now
+13:57 < sulix> I am very confused.
+13:57 < sulix> It generates bitmaps of circles in varying shades of red?
+13:58 * sulix decides to actually read the code.
+14:03 < sulix> Ah: I see what it's doing now.
+14:16 <@matches> Your first comment was pretty accurate :S
+14:17 <@matches> I was trying to obtain some amazing animation of a circle that hopelessly collapsed or exploded or something
+14:19 < sulix> I'm slightly terrified that it's generating a vector of points.
+14:19 < sulix> On the other hand, it looks like the rest of the world is realising what a mistake making OpenGL 3 terrifying was.
+14:19 <@matches> Yeah that's a bit lazy
+14:19 <@matches> Although, is returning a vector optimisable?
+14:20 < sulix> In C++11 it is.
+14:20 < sulix> (But not C++98)
+14:20 <@matches> C++11 is growing on me
+14:20 < sulix> Yeah: I've found the same thing.
+14:21 < sulix> I'm a bit scared about what that means, though.
+14:21 < sulix> Maybe one day I'll think boost was a good thing, and then I'll truly be lost.
+14:21 <@matches> Hahaha
+14:21 <@matches> The lambdas remind me of Javascript :S
+14:22 < sulix> I think lambdas are one of those things that are good for you in moderation, but poisonous in large quantities.
+14:22 <@matches> Probably
+14:23 < sulix> I won't be around on Monday, btw, so I'll miss the meeting.
+14:23 < sulix> (Also I'm missing out on Codejam, sadly)
+14:23 <@matches> No!
+14:23 <@matches> (To both of those things)
+14:24 <@matches> Oh god that means I need to make double the progress
+14:25 < sulix> I spoke to Tim, he said that it might be worth cancelling the meeting altogether.
+14:26 <@matches> Haha
+14:26 <@matches> I'm not sure if I should take that as a good or bad sign
+14:27 <@matches> I'm not going great with the literature review
+14:28 < sulix> I rated a bit of it.
+14:28 < sulix> (Though there wasn't a submit button, and it took me a few goes to get through the Turing test)
+14:28 <@matches> Page 20?
+14:28 <@matches> Haha
+14:28 <@matches> The turing test defaults to the accepted answer though!
+14:28 <@matches> You have to actually change it to get it wrong
+14:29 < sulix> Yeah, I thought it was a trick question.
+14:29 <@matches> Maybe I'll give Tim a slightly less joke-worthy version of Rate My LitReview when the draft is done
+14:29 <@matches> ... when hell has frozen over...
+14:29 <@matches> Whichever comes first
+14:31 < sulix> You should read James Mickens' USENIX articles: mkdir -p vogl/vogl_build/bin/release64 && cd $_
+14:31 < sulix> cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_X64=On ../../..
+14:31 < sulix> make -j 10
+14:31 < sulix> (Also I should paste the right thing in)
+14:31 < sulix> http://research.microsoft.com/en-us/people/mickens/
+14:32 <@matches> Ah yes, I will read those at some point
+14:32 * matches downloads the first one, telling himself he will not read it until working on the lit review
+14:33 * matches reads it anyway
+14:33 * sulix feels guilty about not doing lit review at the moment, too.
+14:40 <@matches> Have you heard of /read Computer Graphics by Hearn and Baker?
+14:40 <@matches> I have the ancient "In the dawn before OpenGL 1.0" version
+14:41 <@matches> There is a section mentioning "GL"
+14:41 <@matches> I don't think they use GPU anywhere, they call them "Display Rasterisers" or something
+14:42 <@matches> Display Processor
+14:43 <@matches> A Display Processing Unit is a Display Processor for a Random Scan (vector) display system
+14:43 <@matches> Input devices are interesting too
+14:44 <@matches> "Input Dials"
+14:44 <@matches> A box of variable resistors basically
+14:45 <@matches> Working with computers in the 70s/80s would have been interesting although probably just as horrible as it is today
+14:45 <@matches> But at least it would have been less "webby"
+14:46 <@matches> Where "How do I centre a div" is a deep philosophical question
+14:48 <@matches> I should probably obtain / read a newer edition of this if I want to put it in my lit review?
+14:48 <@matches> Although it is referrring to the same papers we had about Bressenheim
+15:14 <@matches> Oh my god they mention precision!
+--- Log closed Thu May 08 17:04:49 2014
+--- Log opened Thu May 08 18:56:39 2014
+18:56 -!- Irssi: #ipdf: Total of 2 nicks [0 ops, 0 halfops, 0 voices, 2 normal]
+18:56 -!- Irssi: Join to #ipdf was synced in 3 secs
+19:55 < matches> Bresenham made a tutorial on rasterisation
+19:56 -!- mode/#ipdf [+o matches] by OperServ
+19:56 <@matches> Bresenham has a nice tutorial about rasterising
+19:56 <@matches> Ties in with the "Since mankind came down from the trees" angle
+19:57 <@matches> "Needlepoint or counted cross-stitch, such as that popularised by the image on a box of Whitman Sampler chocolates..."
+19:57 <@matches> I'm not sure how to relate the rasterisation stuff to the precision stuff
+19:58 <@matches> You have to make a pretty big rounding error to end up in the wrong pixel
+19:59 <@matches> Hearn and Baker mention rounding errors as being one reason why you don't want to use floats and then round them when rasterising things
+19:59 <@matches> The (bigger) reason being that floating point operations are expensive
+20:00 <@matches> They say pixels could move from the line in the DDA algorithm for long lines... I wonder how long they mean... 1e38 pixels? :P
+20:02 <@matches> I want to actually make a drawing of things that look different due to rounding errors dammit!
+20:03 <@matches> None of this "here is a sentence or two of handwaving"
+20:04 <@matches> Maybe rounding errors were a problem on computers with 8 bit floats and terrible resolution displays :P
+20:04 <@matches> Except the worse your resolution the less you'd notice rounding errors
+20:04 <@matches> Well the more you'd notice them, the less they'd happen?
+20:04 <@matches> I don't know
+20:05 -!- mode/#ipdf [-o matches] by matches
+20:30 < sulix> These were recommended: http://www.amazon.com/Forman-S.-Acton/e/B001IYTXGY/?_encoding=UTF8&tag=mollrock-20&linkCode=ur2&qid=1358713701&camp=1789&sr=8-3&creative=390957
+20:30 < sulix> (By a blog post, which turned out not to be about floating point precision, but does mention it: http://mollyrocket.com/casey/stream_0009.html )
+21:21 < matches> I'll look at them at some point
+21:22 -!- mode/#ipdf [+o matches] by OperServ
+21:22 <@matches> I'll look at them at some point
+21:22 <@matches> I sort of got bogged down explaining how lines are drawn :S
+21:22 <@matches> Graphics is complicated dammit
+21:22 <@matches> I'll probably get more done if I just write about everything no matter how irrelevant
+21:23 <@matches> Sooner or later I'll actually write something important and the rest can be appendicised
+21:23 <@matches> Hopefully
+21:25 <@matches> Oh dear, I have located some primitive form of blog
+21:26 <@matches> Well, it talks about things, so I'll reference it...
+21:26 <@matches> "The good-looking textured light-sourced bouncy fun smart and stretchy page"
+21:26 <@matches> It's generally best to not go up a directory from the page you are looking at
+--- Day changed Sun May 18 2014
+15:47 <@matches> So things are due soonish
+15:47 <@matches> :S
+20:09 <@matches> Are you alive, because I don't think I'm alive
+20:10 -!- Irssi: #ipdf: Total of 2 nicks [1 ops, 0 halfops, 0 voices, 1 normal]
+20:11 <@matches> I'm feeling pretty guilty about all that work I didn't do last week...
+20:47 * sulix agrees entirely.
+22:11 <@matches> I give up
+22:11 <@matches> I will just have to face disappointment O'clock tomorrow
+22:22 < sulix> I still have to put more work in before I feel I even deserve disappointment, I think... :/
+22:23 < sulix> I made the mistake of deleting the irrelevant bits from my lit review, and now there's almost nothing left!
+--- Day changed Mon May 19 2014
+08:03 < sulix> At the risk of causing terror: is your final Lit review due on Friday too?
+08:05 * sulix has discovered that his is, and is currently trying to work out how to type in the foetal position.
+09:59 <@matches> Yeah it's due on Friday
+09:59 <@matches> Today is not off to a good start
+10:00 <@matches> I missed an 8am lab but I can't blame the 2 buses I missed because I actually forgot about it
+10:00 <@matches> Then I missed the 2 buses
+10:00 < sulix> Ouch.
+10:00 <@matches> I think missing my tutorial this afternoon is a bad idea but on the other hand... lit review
+10:02 < sulix> I'm frantically writing irrelevant stuff now.
+10:03 < sulix> I'm a little concerned about my entire section on "Document Formats" basically only referencing some specs and "Pixels or Perish".
+10:03 <@matches> That's what I do
+10:03 < sulix> Whereas I have like 20 references for graphics papers that are almost totally irrelevant.
+10:04 <@matches> I have a reference for shading on a vector display
+10:04 <@matches> That's pretty irrelevant
+10:04 < sulix> I've started referencing data structures that are "kinda similar I guess" to the Quadtree, as well. :/
+10:05 <@matches> I ham fisted it in with the paper about embedding 3d figures in documents
+10:05 <@matches> Like "in the 70s even though people had algorithms for things they still drew the diagrams by hand!"
+10:05 < sulix> Peasants!
+10:06 <@matches> My section on number representations is pretty shite
+10:06 <@matches> I still haven't finished floats
+10:06 < sulix> Mine is currently under construction, as it were.
+10:06 <@matches> And the whole point is supposed to be that floats are not good enough
+10:07 < sulix> I've got a terrible thing about floats, but have started talking about arb. precision floats now.
+10:07 <@matches> All I know about the alternatives are that they are basically still floats
+10:07 <@matches> But with more bits...
+10:07 < sulix> I also have some maths I made up that is maybe wrong.
+10:07 <@matches> Will you be here in time for doom O'clock?
+10:08 <@matches> *cough* I meant eleven
+10:08 < sulix> We can but hope.
+10:08 < sulix> I'm sort-of counting on the meeting not happening until 11:20 or so. :/
+10:09 <@matches> I'll show him Rate My Lit Review
+10:09 <@matches> That'll distract attention from the lack of Lit Review
+10:09 <@matches> I'm also assuming no one is ever going to read these IRC logs
+10:09 < sulix> We can but hope.
+10:10 < sulix> I'm feeling dirty because I've just referenced the java standard library.
+10:10 < sulix> Out damnéd
+10:10 < sulix> java.math.BigDecimal.
+10:15 <@matches> I was going to reference that at some point
+10:16 <@matches> I feel like you've made more progress than I have been
+10:17 <@matches> Possibly the decision to sleep last night was a poor one
+10:26 < sulix> Having done the opposite: it wasn't.
+10:30 <@matches> Argh I just got the icedove reminder for the meeting
+10:32 <@matches> So I washed out my Guild (TM) Keep Cup (TM) this morning and now my tea tastes like detergent
+16:37 <@matches> We didn't get the random asking about photoshop in here
+16:37 <@matches> I feel left out
+22:49 <@matches> sjy in #ucc mentioned Knuth's Metafontbook in regards to rendering fonts at infinite precision
+22:49 <@matches> Yet another thing to get around to reading :S
+22:49 <@matches> Before Friday :S
+22:50 <@matches> Wednesday I guess if we meet Tim's deadline for a draft :P
+23:08 <@matches> I guess I was meaning to reference the TeX book at *some* point
+23:08 <@matches> So many things
+23:08 <@matches> Oh dear it's 11pm already
+23:08 <@matches> :-(
+23:09 <@matches> Ok, so
+23:09 <@matches> Metafont seems to basically be symbolic ways to define fonts
+23:10 <@matches> Also Beziers
+23:10 <@matches> All the beziers
+23:10 <@matches> Good
+23:11 <@matches> I was on the right track when I said Beziers were really important
+23:11 <@matches> Knuth is so detailed
+23:12 <@matches> Now I feel guilty about my cartesian line
+23:12 <@matches> That I didn't reference Rene Descartes La Geometrie 1637
+23:12 <@matches> I'm a monster
+23:15 <@matches> I think instead of thinking of things as either interpreted or dom-y like Hayes does, the best way is to think about "What is in the document (eg: DOM)" and "How it is drawn" and you can either have your format care about both things or just one but obviously the most useful formats allow for both
+23:16 <@matches> Actually scratch that
+23:16 <@matches> I don't know anymore
+23:16 <@matches> It's too philosophical
+23:16 * matches goes back to floating point nubers
+23:18 <@matches> So I wonder how much of PostScript is a shameless rip off of METAFONT
+23:18 <@matches> It's not like you have to give credit when you are trying to sell something
+--- Day changed Tue May 20 2014
+09:29 <@matches> So it's quite easy to do a
+09:29 <@matches> "fractal" in SVG/Javascript
+09:29 <@matches> Where easy does not necessarily mean it isn't horrifying
+09:30 <@matches> Aaand there goes all my RAM
+21:43 <@matches> Casually slipping in a footnote directing the reader to rabbitgame.net in my lit review...
+21:43 <@matches> So my webby documents section is probably my least shitly written, or maybe that's just because it has pointless pretty pictures in it
+21:44 <@matches> It is basically
+21:44 <@matches> "Here are the w3c standards"
+21:44 <@matches> "Here are some pretty pictures made with SVGs, can't you just see the DOM leaching out of them?"
+21:44 <@matches> :S
+21:45 <@matches> I'm not sure how well I am treading the line between actually reviewing literature and just giving examples of things
+--- Day changed Wed May 21 2014
+12:09 <@matches> PDF is a mess of a "standard"
+12:09 <@matches> As are all useful things I suppose
+12:09 <@matches> As far as I can work out
+12:09 <@matches> It is not a DOM but a graph
+12:10 <@matches> However, it is also PostScript-y
+12:10 <@matches> But they deal with "interactivity"
+12:10 <@matches> By including XHTML
+12:10 <@matches> And having an "action dictionary" which is literally just a string of javascript
+12:11 <@matches> I just
+12:11 <@matches> Can't even begin to understand how it all works
+12:12 <@matches> But yeah, not really "Crippled Postscript" so much as "Everything including the kitchen sink except for a few bits of Postscript"
+12:13 <@matches> So the Postscript part of it is no longer turing complete, but I don't think you can pretend something in which you can stick arbitrary Javascript isn't turing complete :S
+12:13 <@matches> Oh and even though they have XHTML-ish stuff their Javascript API is totally different to W3Cs
+12:13 <@matches> Hooray
+12:14 <@matches> I suppose the fact that nothing except Adobe products seem to actually use Javascript/XHTML stuff is telling us something about this approach
+12:15 <@matches> I reckon the ideal standard
+12:15 <@matches> Would probably be the DOM but with the "we actually care about efficiency" parts of PDF
+12:18 <@matches> The interactivity of web pages combined with the actually professional looking type setting of PDF
+12:18 <@matches> Or just plain text files
+12:19 <@matches> Plain text files are an underapreciated Document Format
+12:23 <@matches> Ah, I think it sort of makes sense now
+12:23 <@matches> PDF uses what is essentially PostScript to construct this graph thing
+12:24 <@matches> And the graph thing can have elements in it that are just "Make this part of the graph the equivelant DOM from this XHTML"
+12:25 <@matches> And it can also have elements that are "Execute this Javascript to dynamically change this graph"
+12:25 <@matches> But the normal elements are just like PostScript as it would be sent to a printer to show the thing statically
+12:26 <@matches> So when it's rendered it is interpreting the Postscripty bits and when its being interacted with it is updating the Postscripty bits
+12:26 <@matches> I *think*
+12:26 <@matches> This is different from the webby standards which don't really specify how things are actually drawn
+12:27 <@matches> No wait it's not
+12:27 <@matches> Argh I don't know
+12:27 <@matches> You can't classify this shit
+12:27 <@matches> Document Goes In -> Pixels Come Out
+12:28 * matches despairs
+12:49 < sulix> You will find (slightly) less despair if you relegate javascript to the footnote where it belongs. :P
+13:07 < sulix> Hmm... the HTML 2 spec looks like it almost got properly IETF standardised. Might just reference that.
+13:12 < sulix> Oh, they obsoleted it and replaced it with a "Just look at w3c" standard...
+13:17 <@matches> But PDF isn't just flattened PostScript
+13:17 <@matches> It is like, everything
+13:17 <@matches> All merged into one horrifying standard
+13:18 <@matches> Oh well
+13:18 <@matches> I made my shape example in PostScript by removing the alpha
+13:18 <@matches> I'm not sure whether there's any point in including it as a figure
+13:18 <@matches> Most of the PostScript file is taken up by the header
+13:19 < sulix> Holy balls, I just looked up the CSS spec. There are like 200 of them.
+13:19 <@matches> Yeah I just used CSS2
+13:19 <@matches> The others are like
+13:19 <@matches> Colours
+13:19 <@matches> Or something
+13:20 < sulix> That's what I'm using, too.
+13:20 < sulix> The tired and tested "what gets top result on google" method of paper selection.
+13:20 <@matches> Closer examination reveals that most of the PostScript header is defining commands to be shorter :P
+13:20 <@matches> Amazing
+13:20 <@matches> Cairo probably needs to get referenced somewhere
+13:21 <@matches> If only so I have a way out of my Javascript in PDF section by saying that Cairo doesn't support it
+13:21 <@matches> I desperately need to escape the Javascript
+13:25 < sulix> I think the secret is to use the phrase "rendering model" wherever possible.
+13:51 <@matches> Dammit
+13:51 <@matches> So I have that wierd shape in both SVG and PostScript now
+13:51 <@matches> The SVG version fits beautifully and is wonderfully concise and you can see how SVG works
+13:51 <@matches> The PostScript version is just like, BLARGH WALL OF TEXT
+13:51 <@matches> ALSO WE DON'T HAVE ALPHA
+13:52 <@matches> So I'm not sure whether to cut just the PostScript one or both of them now :S
+13:53 <@matches> PDF looks distinctly not like it is just PostScript the more I think about it
+13:53 <@matches> It's like "We are using the same model as PostScript in that commands go in and pixels come out"
+13:54 <@matches> By that logic SVG is also the same
+13:54 <@matches> I think what I should do is just make an appendix
+13:54 <@matches> "A Shape in 20 Document Formats"
+13:56 <@matches> SVG really is the most concise compared to PS and PDF
+14:53 <@matches> Right I can simplify the god awful mess of PS a bit
+14:54 <@matches> I'm hoping I can just say "Here is the PS reference and here is some PostScript as you can see it is interpreted-ish"
+14:54 <@matches> Cairo appeared to draw each element backwards and reverse it after drawing it
+14:54 <@matches> It is stupid
+14:57 <@matches> Like, why bother doing definitions like m == moveto etc
+14:57 <@matches> If you're just going to stick pointless crap in
+14:57 <@matches> My document is half the size without using single letter definitions
+15:31 < sulix> Welp. The wrath of Tim is upon us...
+15:41 <@matches> I'm choosing to latch onto the "quite good" rather than "some way to go"
+15:45 <@matches> It sort of sounds like "Well at least you gave me a pdf file" :P
+15:48 < sulix> One day, all anyone will use are ipdf files...
+15:50 <@matches> Right, TeX is very different from PostScript I think
+15:50 <@matches> At least, pure tex
+15:50 < sulix> Also, holy mackerel, I might have just found a paper on precision in document formats...
+15:50 <@matches> :O
+15:50 < sulix> It even quotes Kahan
+15:50 <@matches> :OOO
+15:50 < sulix> https://www.tug.org/TUGboat/tb28-3/tb90beebe.pdf
+15:50 <@matches> What is it
+15:50 <@matches> Emergency rewrite of entire lit review
+15:51 < sulix> It's a bit TeX specific, but still.
+15:51 <@matches> That's alright
+15:51 <@matches> It ties in amazingly with my decision to hamfist TeX and Metafont into the lit review
+15:52 <@matches> Although I'm not sure it is wise because it means I have to talk about fonts and things
+15:53 <@matches> I wonder if "Fonts are just bezier curves" is sufficient
+15:53 <@matches> They are always treated seperately to curved paths
+15:53 <@matches> Which is understandable because it's a bit inconvenient if you want text in a document to have to define the paths for each glyph
+15:54 <@matches> Anyway I'm glad my assertion that Beziers are the only curves we care about is proving true
+16:33 <@matches> Are you in a position to retrieve this "envelope"
+16:57 < sulix> Not tonight: I'm going to pick it up tomorrow morning.
+16:58 < sulix> And hopefully replace it with a sparkling, glorious review of literature.
+17:00 <@matches> :(
+17:00 <@matches> I cannot concentrate now
+17:00 <@matches> Because I haven't read the comments, I could be doing everything wrong!
+17:02 <@matches> Admitedly I'm technically "working" right now
+17:27 < sulix> My "Document Format Taxonomy" is almost complete... Just need to add SVG.
+17:28 < sulix> (And close my eyes and assert that Microsoft Word documents are not actually documents or something)
+17:28 <@matches> I am jealous
+17:29 <@matches> I just added PostScript it's not particularly well written
+17:29 < sulix> (I don't have any pretty pictures or code, though)
+17:29 < sulix> I've discovered that, despite having totally different numbers for "implementation limits", the PostScript and PDF specs are (a) talking about the same data types and (b) lying.
+17:32 <@matches> Bahaha
+17:32 < sulix> Do you know where the SVG spec mentions precision?
+17:33 <@matches> Ah, I regret not noting the page number
+17:33 <@matches> But a text search should find it
+17:33 <@matches> It specifically says things
+17:33 <@matches> I am interested in whether or not Javascript is subject to the same requirements
+17:34 < sulix> All I've found is "must be correct within 1px at 1:1 zoom", and "It is suggested that viewers attempt to keep a high degree of accuracy when zooming".
+17:35 <@matches> There's something that is about IEEE floats
+17:35 < sulix> Aaah... and a "High-Quality Viewer" must support at least double precision on coordinate system transforms.
+17:35 < sulix> But "IEEE" does not show up in a search of the spec.
+17:36 <@matches> Ah right
+17:36 <@matches> My brain just inserts IEEE whenever I hear "single" or "double" now
+17:36 <@matches> "An IEEE Double Episode of MasterChef!"
+17:36 <@matches> (Which would probably be infinitely more exciting)
+17:37 < sulix> (Or would it be NaNly more exciting...? :P)
+17:38 <@matches> Speaking of "where things are" are we meant to reference page numbers in standards?
+17:38 <@matches> I guess I'll find out when I read Tim's comments
+17:39 <@matches> Excellent my lab finished 20 minutes early
+17:39 <@matches> And also 40 minutes later than the other demonstrators :S
+17:40 <@matches> Do you want me to pick up your comments and scan them and email them to you? :P
+17:40 < sulix> That'd be great.
+17:40 < sulix> Also probably depressing.
+17:41 < sulix> But great.
+17:41 <@matches> Alright, ETA Transperth + Scanner is probably broken O'clock
+17:42 < sulix> I'll savour the blissful ignorance.
+19:50 <@matches> I don't think scanning is worth it, I'll just spam the feedback into this channel
+19:50 <@matches> First up, David's Lit Review
+19:50 <@matches> There is either "Gool" or "Cool" or possibly "Good" written and underlined on the first page
+19:51 <@matches> The opening paragraph is "A little overdramatic?"
+19:51 <@matches> (Since it's a question, I'd like to voice a "No" opinion here)
+19:51 <@matches> The DOM in a footnote is not defined
+19:52 <@matches> Page 2
+19:52 <@matches> There is a tick
+19:52 <@matches> A question mark in regards to the hyphenated bit in the rendering paragraph
+19:53 <@matches> Say "avoid" instead of lack
+19:53 <@matches> Add what the "basic primitives" actually are
+19:53 <@matches> There appears to be an issue with hyphenated phrases the hyphens are circled
+19:53 <@matches> Another tick!
+19:54 <@matches> Oh, you have a $2^64 - 1$\footnote{} which is unfortunate because it looks like $2^64 - 1^2$
+19:54 <@matches> That footnote (probably others?) would work in the paragraph without being footnote
+19:54 <@matches> Fullstops go after \cite{}
+19:55 <@matches> A tick (in regards to the quadtree diagram)
+19:55 <@matches> The concluding comment
+19:56 <@matches> "OK, Much to do (underline) There doesn't seem to be much scholarly references used. You have enough, but you seem to cite them in the context of their contributions to standards as opposed to how they addressed a research question or open problem"
+19:57 <@matches> And (not even our references lists are safe!)
+19:57 < sulix> Oh dear.
+19:57 <@matches> Where referencing web pages, include the date retrieved
+19:57 <@matches> That's it
+19:57 <@matches> I shall move on to my own for completeness although you might not need to care
+19:58 < sulix> Phew, that's not quite as horrible as it could have been, I guess.
+19:58 <@matches> I also have "Good"
+19:58 <@matches> There are some "I didn't read this bit but it had words that seemed vaguely relevant" ticks in Chapter 1 (Introduction) and 2 (Proposal)
+19:59 <@matches> Sorry Tim if you read this
+19:59 <@matches> But when I mark lab reports for Physics that's usually where I put the ticks :P
+19:59 < sulix> (The secret comes out)
+20:00 <@matches> (In my defence I did spend two hours marking the reports this morning and I am paid for none of them, so...)
+20:01 <@matches> (It's the bits that I scribble all over that are where the marking gets done)
+20:01 <@matches> (I think I've covered myself in case the lawyers of any of my students read this channel now, so I will resume my story...)
+20:02 <@matches> Attention is called to the many glaring instances of [?] and "Refer to Section ?"
+20:02 <@matches> :S
+20:02 <@matches> I should probably define a vector image before comparing it to a raster image
+20:02 <@matches> Incidentally my Fox looks amazing
+20:02 <@matches> On printed paper
+20:03 <@matches> (Tim didn't say that, that's just my modest opinion)
+20:03 <@matches> Ahem.
+20:03 < sulix> Can you see the difference between the vector and bitmap versions easily?
+20:04 <@matches> At the original scale there is, alas, a very slight fuzziness
+20:04 <@matches> But I reckon the markers will be old and blind
+20:04 <@matches> Hmm, I should either be more careful about what I say here or stop logging this channel...
+20:04 * sulix hopes they don't read that.
+20:04 <@matches> Sorry markers
+20:04 <@matches> I worship your power
+20:04 <@matches> Please do not smite me
+20:05 <@matches> The scaled up version is interesting
+20:06 <@matches> It looks a bit like your circle with the blocky non-anti-aliased bit but actually anti-aliased by the pdf viewer
+20:06 < sulix> I guess the scaling would be done by the printer's postscript RIP.
+20:06 <@matches> Yeah I guess
+20:07 < sulix> (Side note: I find the whole idea of Postscript interpreters being called RIPs somewhat fitting)
+20:07 <@matches> The PDF decides not to antialias it and converts it to Postscript and then the postscript interpreter adds its own antialiasing?
+20:07 <@matches> I don't know
+20:07 * sulix joins the "SVG is the least broken format" club.
+20:07 <@matches> It's very tempting to descend into footnote madness with this lit review
+20:07 <@matches> "By the way, this very document is an example of this thing!"
+20:07 <@matches> Etc
+20:08 <@matches> Moving on
+20:08 <@matches> The point of talking about vector displays at all is questioned (at least I think that's what the "Why?" refers to here)
+20:08 <@matches> Or it could be "Why is there yet another ?? in this paragraph" I guess
+20:09 <@matches> But probably the former
+20:09 <@matches> I do not have space to include Bresenham's algorithm
+20:09 <@matches> Oh boy, he's going to love what I did with the SVG and Postscript images...
+20:09 <@matches> But I am glad I do not have to actually explain Bresenham's algorithm because it's actually annoyingly detailed
+20:11 < sulix> All sane descriptions of Bresenham's algorithm end up being cascades of "By symmetry" anyway.
+20:11 <@matches> I need to actually find a reference that applied Wu/Bresenham directly to a non-straight line
+20:11 <@matches> You said Bresenham adapted his algorithm to circles but I don't think I'll bother unless someone adapted them to beziers
+20:12 <@matches> Bresenham's paper on rasterisation techniques basically says "Compute some points close enough together and then just connect them with straight lines"
+20:12 <@matches> But I think things might have advanced since the 1980s
+20:12 < sulix> Well, we can compute points that are closer together and draw more lines, I guess.
+20:13 <@matches> Next, Tim wants an example of a spline
+20:13 <@matches> (Oh boy have I got that covered)
+20:13 <@matches> My mathematics terminology on Beziers is not really great
+20:14 <@matches> Well it's right but confusing maybe
+20:14 <@matches> Or I just need to say "t is a trajectory parameter"
+20:14 <@matches> Haha
+20:15 <@matches> He found one of my "????" that is actually just me typing question marks and not a broken reference
+20:15 <@matches> The *entire* section on shading and compositing has a big question mark
+20:15 <@matches> Oh dear
+20:15 <@matches> I just finished writing the compositing bit
+20:16 <@matches> I hope the question mark means "Why isn't this written" and not "Why is this in here"
+20:16 <@matches> Because it is quite useful for an excuse to say PostScript can't do alpha
+20:17 <@matches> I need to refer to the IM (I really don't think that's a thing) and DOM when citing Hayes
+20:17 <@matches> "I don't think Turing Completeness is essential" (Big cross through the Crippled Interpreted Model)
+20:17 <@matches> Fair enough
+20:17 <@matches> A tick appears
+20:18 <@matches> Predictably in the web based documents part
+20:18 <@matches> I need to explain why Ipython is cool if I want to talk about it
+20:18 <@matches> My entire section on Precision as defined in the various formats is ?
+20:20 <@matches> My still to be completed/started section on Graphics APIs, GPUs and Arbitrary Precision is three question marks and "How's all this going"
+20:20 <@matches> The progress report gets a single tick
+20:20 <@matches> And the references have similar issues
+20:20 <@matches> Well
+20:21 <@matches> I'll take a few minutes to quiver in terror
+20:21 <@matches> But I think if I can just find a way to not sleep and still maintain productivity, I might be able to pull this off
+20:22 <@matches> Interestingly he didn't call me out for just talking about standards
+20:22 <@matches> But now I realise that's because I didn't have all the crap I've just written on standards in there
+20:23 < sulix> It's going to be a long night, but I think we'll manage it.
+20:23 <@matches> Mine will be too long but I don't care
+20:24 <@matches> I'll ask for an extension to prepare a condensed version if I must :P
+20:28 <@matches> It's kind of funny I've been spending more time making my vector image in SVG and PostScript nice than actually writing about either of those standards
+20:50 <@matches> Argh the idea of making my koch snowflake example for PS just got in my head
+20:50 <@matches> Which would be brilliant I guess if the topic was still "Fractal Document Formats"
+20:50 <@matches> It probably would be useful if I could demonstrate precision issues..
+20:50 <@matches> NO
+20:50 <@matches> MUST WRITE
+20:50 <@matches> WORDS
+20:50 <@matches> NOT PICTURES
+20:51 <@matches> But still it would make the PostScript and SVG sections consistent with each other...
+20:51 <@matches> NO
+20:51 <@matches> Must control urge to put pointless pictures in
+20:51 <@matches> No matter how much it seems like a good idea
+20:51 <@matches> And not pointless
+20:52 <@matches> Help I'm losing this battle
+20:53 <@matches> It is probably actually a better way of making a Koch curve than the hideous Javascript parsing of strings version
+22:50 <@matches> By the way, you can totally have "pre layout" stages in PostScript since you can define your own operators
+22:50 <@matches> Or do I misunderstand your sentence
+22:50 <@matches> Oh well it sounds smart anyway
+22:51 <@matches> In fact it's a lot more concise than my DOM-y section
+22:52 <@matches> I should sign my Lit Review as Captain Obvious
+22:57 < sulix> My current version does have a "PostScript programs typically embody documents which have been type-
+22:57 < sulix> set, though as a turing-complete language, some layout can be performed
+22:57 < sulix> " sentence.
+22:57 < sulix> by the document.
+23:01 * sulix is still a little bit concerned about how he should reference things for their solutions to open problems rather than their contributions to standards.
+23:03 <@matches> I think I am managing to do it
+23:03 <@matches> I will commit something at some point
+23:03 < sulix> I'm hoping that rewriting most of the rendering section with painful discussions of algorithms will do it.
+23:03 <@matches> An example is Porter and Duff Compositing
+23:04 <@matches> Because PostScript doesn't have alpha and I am really hoping that's just because Adobe had moved on to PDF by the time alpha was a thing
+23:04 <@matches> And not because they thought alpha was dumb :P
+23:05 <@matches> So I can relate Porter and Duff's model to the standards that do use it and say how it solves a problem that the standards that don't use it still have
+23:05 <@matches> And then I can sit back in satisfaction
+23:05 <@matches> And realise this says fuck all about precision
+23:06 <@matches> But at least by talking about it, I have eliminated it from the set of things we need to worry about when talking about precision :P
+23:06 < sulix> I've got a section which basically goes through all of the different document formats and looks at what their specs say about precision now.
+23:06 <@matches> Yeah I have that, but it was dot-pointed
+23:06 <@matches> I thought that would be OK actually but it has a question mark here... :S
+23:06 < sulix> Basically most of them say "implementation-defined" anyway.
+23:06 <@matches> Oh right because I was saying random stuff about how Postscript *used* to not have IEEE
+23:07 <@matches> Yeah it is odd that the standards don't actually reference IEEE
+23:07 <@matches> You'd think, since it's a standard...
+23:07 <@matches> Instead they just say "single" or "double" or "it might be single if you're lucky but we don't care really"
+23:08 <@matches> I assume "single" is widely accepted to mean IEEE single
+23:08 < sulix> From my reading of the Postscript spec, it says basically "We've put IEEE here, but ask your printer manufacturer because they could be using anything for all we care."
+23:08 <@matches> Ah I will check that more carefully
+23:08 <@matches> But it sounds about right
+23:08 < sulix> They give "typical limits" for their data types, but specifically do not specify what they are to be implemented as.
+23:08 <@matches> I don't think I have the time to look at what PostScript did historically before IEEE-754 although it would be kind of interesting to know
+23:09 <@matches> PostScript also does a bunch of silly maths because of units
+23:09 < sulix> The idea being that each postscript interpreter could do whatever they liked.
+23:09 <@matches> Cool
+23:09 <@matches> I should know this already :S
+23:09 <@matches> I just included a single character as a figure
+23:10 <@matches> But I want to actually work out how to do it in LaTeX by setting the size of the font appropriately
+23:10 < sulix> The PDF spec says pretty much the same thing, but notes that Adobe's implementation uses "Mostly IEEE singles" but "used to use 16.16 fixed point" and "still uses it for some things"
+23:10 <@matches> I did see that
+23:10 < sulix> TeX using 14.16 fixed point.
+23:10 < sulix> DVI uses "up-to 32bit" signed integers.
+23:11 <@matches> So basically no one actually uses IEEE for anything :P
+23:11 <@matches> Good work
+23:11 <@matches> I shall panic a bit and then try and actually do that work myself
+23:11 < sulix> SVG uses "implementation defined" or "double-precision floating point" "for coordinate transforms" if you want to be certified "High Quality"
+23:12 <@matches> I saw that one
+23:12 <@matches> But I'm skeptical about how this plays with Javascript
+23:12 <@matches> Not for High Quality even, just in general
+23:12 < sulix> Javascript numbers are always IEEE 754 doubles.
+23:13 <@matches> Ah thanks
+23:13 < sulix> (Even their integers are IEEE 754 doubles, which just happen to be integers)
+23:13 <@matches> Yes I have heard this before
+23:13 <@matches> From you probably :P
+23:14 < sulix> I don't have a source for that, and I'm not going to read the ECMAscript spec to find one, though.
+23:16 <@matches> Oh right, Javascript is actually ECMAscript
+23:16 <@matches> I forgot that
+23:17 <@matches> Dammit I am struggling to stay awake here
+23:17 <@matches> I'm not sure whether it's healthier to try to not sleep and give Tim a draft tomorrow and demand he read it in enough time to make last minute changes
+23:18 <@matches> Or sleep and then be more coherant tomorrow
+23:18 <@matches> I guess I'll try and finish a couple more sections
+23:19 < sulix> I'm going to try to finish this tonight.
+23:20 * sulix has another assignment due Friday that needs significant work.
+--- Day changed Thu May 22 2014
+00:47 <@matches> So X just managed to totally shit itself
+00:47 <@matches> Time to see when I last pressed Ctrl-S
+00:48 <@matches> Oh good (I typically press it once per sentence)
+00:48 <@matches> I hope it wasn't one of my SVGs that broke everything
+00:49 <@matches> Making all my figures in SVG
+00:49 <@matches> Lovingly hand written
+00:49 <@matches> I'm not sure that was a good idea
+01:43 <@matches> Heh, converting SVG to PS in Inkscape appears to introduce rounding errors of up to 0.1 of whatever unit PS is using
+01:44 <@matches> 1.25*56
+01:45 <@matches> Disregard I appear to have mistaken this terminal for a calculator
+01:45 <@matches> They do look similar at this hour in the morning
+01:49 < sulix> I'm seriously doubting whether starting to write stuff about how all of the rasterizing algorithms work was a good idea.
+01:49 <@matches> Haha
+01:49 <@matches> I don't really have much rasterising as such
+01:49 <@matches> Straight lines
+01:50 <@matches> Beziers aren't really "rasterising" so much as defining curves
+01:50 <@matches> Then I mention fonts and how they are all bezier-ish
+01:50 < sulix> I've just spent about an hour trying to prove that bresenham's algorithm can be made to not depend on any coordinates outside the screen.
+01:50 <@matches> Then I have a bit on shading that I can't do
+01:50 <@matches> :S
+01:50 <@matches> That's probably not important
+01:50 <@matches> To quote Tim in my thesis regards to actually explaining algorithms
+01:50 < sulix> It turns out that if you clip the endpoints (even correctly), you adjust the slope of the lines slightly.
+01:51 <@matches> "No you don't have space. [...] details should be left to where they are useful"
+01:51 <@matches> Having said that absolutely none of this is "useful"
+01:51 < sulix> To fix it you have to initialize bresenham's "accumulated error" properly.
+01:51 <@matches> That sounds sort of relevant
+01:52 <@matches> Well I just copied some SVG into PostScript and discovered that the coordinates are all reflected :S
+01:52 < sulix> My choices for referencing this is either a textbook I don't have that "apparently mentions this" or a blog post which rants about it a bit.
+01:52 <@matches> Bahaha
+01:53 <@matches> That sounds like work for the final lit review rather than this one
+01:53 < sulix> Still need to work out how to actually work in how my references solved problems rather than contributed to standards or whatever.
+02:05 <@matches> minipage for latex is great by the way
+02:06 <@matches> Like <div> but not awful
+02:40 <@matches> Oh year
+02:40 <@matches> The best spline curve example ever
+02:41 <@matches> Fuck it took about 3 hours to do that
+02:41 <@matches> Dear god
+02:41 <@matches> Ergh remind me to go censor the log before Friday 1am
+02:50 <@matches> I pushed my references changes by the way
+02:51 < sulix> Yay merging!
+02:51 <@matches> Oh I forgot the actual pdfs but whatever
+02:51 <@matches> I am jealous of your actual concise and to the point lit review
+02:51 <@matches> Mine suddenly exploded into figures
+02:51 <@matches> I should stop
+02:51 <@matches> I think I will delete the Shading section
+02:52 <@matches> No wait it would be a gap to take it out now
+02:52 <@matches> Argh
+02:53 <@matches> I will just have to resist the urge to put a diagram in showing how shading works
+02:53 <@matches> All these diagrams will probably kill me
+02:53 < sulix> I'm thinking of scrapping chunks of the Rendering section of mine just so I don't have to finish them and can go to sleep.
+02:54 <@matches> Tim did seem strongly in favour of covering the rendering stuff
+02:54 <@matches> At least referencing the papers and giving the definitions of things if not actually how to render them
+02:55 <@matches> Anyway I think Beziers at least are important
+02:55 <@matches> I'm discovering a few interesting things about SVG
+02:56 <@matches> The path definitions are basically exactly the same as postscript's commands except less stack-y
+02:56 <@matches> But it has relative commands as well
+02:56 <@matches> Which is interesting because if you have a really really long curve defined with relative commands
+02:56 <@matches> Maybe, just maybe, it will actually cause a precision issue
+02:57 <@matches> I doubt it though
+03:00 <@matches> Well good luck, I am going to sleep
+03:01 < sulix> Thanks. I will see what I can say about Béziers.
+03:38 * sulix collapses.
+08:07 <@matches> Nice work
+08:07 <@matches> Mine is too detailed I think
+08:07 <@matches> It's horrible because now I'm committed to following through on that level of detail everywhere
+08:09 <@matches> Removing detail feels like murder
+08:12 <@matches> Would you be offended if I cited your lit review as a "more concise" overview for the bored reader? :P
+14:28 < sulix> So apparently the entire internet is talking about Bézier curves today.
+14:28 < sulix> This would have been really useful, say, yesterday.
+14:30 < sulix> Also this page looks amazing... http://pomax.github.io/bezierinfo/
+14:39 <@matches> Haha
+14:39 <@matches> I think I've got the Beziers covered
+14:39 <@matches> If you could just hop over to ratemylitreview and check me on that...
+14:39 <@matches> :P
+14:42 < sulix> Ratemylitreview has broken some of the equations...
+14:46 <@matches> If I had time I would include a "rate ratemylitreview" field
+14:46 <@matches> I sent an email
+14:46 <@matches> Now to fear the wrath
+14:47 <@matches> Half time
+14:48 <@matches> Haha I'm somewhat regretting choosing such condescending ratings
+14:49 < sulix> I got terrified seeing that email before I realised it was from you.
+14:49 <@matches> Bahaha
+14:49 <@matches> Well I have to give him something
+14:50 < sulix> You should clearly make the ratings be all amazing, like: "Good, Great, Amazing, Truly Spiffing, Superlative and \"Everything in creation has been leading up to this page of my Lit review\""
+14:51 <@matches> You can POST your own ratings but expecting that might be a bit much
+14:51 <@matches> They are emailed to me as text and they are also stored in the database as text
+14:51 <@matches> Not the most objective of systems :S
+14:51 <@matches> I thought the ratings covered all the bases though
+14:52 < sulix> You could always do what the Shakespeare proramming lanugage does. Positive adjectives +1, negative adjectives -1.
+20:18 <@matches> I haven't said half of what I thought I should about floats
+20:18 <@matches> Tim has been scarily silent :P
+20:19 <@matches> I guess I will assume that means everything is FINE
+20:19 <@matches> I finally got my Table of Contents and things to not take up 6 pages
+20:20 <@matches> I have to resist the urge to add some snarky comments to my section on LaTeX
+20:22 <@matches> About how in theory you don't have to worry about where things go but in practice you spend hours doing horrible things like arbitrarily adding vertical space to force something into position because the anchor position doesn't take into account your line spacing and thus isn't where you expect and the next element overlaps things as a result
+20:22 <@matches> Blargh
+20:22 < sulix> Just stumbled upon a mention of numerical precision causing issues with Wu's algorithm in a book.
+20:22 <@matches> Cite it
+20:23 <@matches> Also give it to me to cite if I can stay awake long enough to read it
+20:23 <@matches> You have contributed some good last minute references
+20:23 <@matches> I seem to have contributed Javascript
+20:23 <@matches> I should be ashamed
+20:24 < sulix> It's in Abrash's Black Book, end of Chapter 42 ("Wu'ed in Haste; Fried, Stewed at leasure"(
+20:24 <@matches> Haha
+20:24 <@matches> My venerable graphics book doesn't even have Wu in it :S
+20:25 <@matches> It also doesn't really properly reference people's papers, or I guess you don't need to in a textbook?
+20:26 <@matches> It gives De Casteljau's method without crediting him for example. It does credit Bezier with things though.
+20:26 <@matches> But they clearly didn't have to worry about putting \cite{} after every single statement
+20:27 <@matches> I'm not sure how well my "I couldn't find a reference, have a look at my website" footnotes are going to go down
+20:27 < sulix> Casey from the Jeff & Casey show did a video blog on Bézier curves and interpolation this morning.
+20:28 <@matches> I really should start reading blogs more, but I was in no position to be watching blogs this morning
+20:28 < sulix> He claims that Bézier did not invent the Bézier curve, so why the hell are they named after him.
+20:28 <@matches> Had I known
+20:28 <@matches> Oh he didn't
+20:28 <@matches> I know that
+20:28 <@matches> That's in Metafont
+20:28 < sulix> I should read Metafont.
+20:28 <@matches> They were named after him because he was the first guy that said "These look useful for things"
+20:28 <@matches> However
+20:28 <@matches> I can't find the paper in a peer reviewed journal
+20:29 <@matches> I think it was for Industry (TM)
+20:29 <@matches> And also in French
+20:29 <@matches> I just cited a paper he did write in English about his experiences with Computer Aided Design
+20:29 <@matches> He doesn't define anything, just shows pictures of nice bezier curvey car bodies
+20:30 < sulix> I saw a bunch of french papers by him, but couldn't be bothered trying to work out which ones were useful.
+20:30 <@matches> De Casteljau's paper is also hard to find
+20:30 <@matches> The order of events was
+20:30 <@matches> 1912 - Bernshtein comes up with the basis polynomials for some sort of mathematical fitting
+20:31 <@matches> 1959 - De Casteljau decides to approximate the curves using his algorithm
+20:31 <@matches> (De Casteljau is only an approximation by the way, but it would converge to the true bezier curve)
+20:31 <@matches> 196? - Bezier does stuff
+20:31 <@matches> 1983/4 - Knuth decides to use them for fonts
+20:32 <@matches> Somehow they ended up in PostScript around that time as well
+20:32 <@matches> Now we're stuck with them
+20:34 <@matches> Hmm I hope my Tensor Equation is right there
+20:34 < sulix> Here's that Wu thing, btw: http://www.jagregory.com/abrash-black-book/#notes-on-wu-antialiasing
+20:36 <@matches> I'm struggling to make my floating point section sound sane
+20:36 <@matches> Too many little details
+20:37 <@matches> Like that you can choose different bases
+20:37 <@matches> What even is a number anyway
+20:38 <@matches> I think the proper way to approach it is talking about a number represented by digits and some numbers take infinitely many digits etc
+20:39 <@matches> Then computers can only fit X binary digits in their registers
+20:39 <@matches> A floating point is basically where you have a fixed point mantissa and then shift the location of the fixed point
+20:39 <@matches> Let's try and ignore the implicit leading one...
+20:40 <@matches> It sort of all falls apart when trying to fit IEEE in there
+20:40 <@matches> This thing is too big as well :(
+20:41 <@matches> Page limits are stupid
+20:42 <@matches> I can't remember what it even is but it's definitely less than what I have
+21:06 <@matches> Ah I see, the aliasing of Wu's line isn't perfect
+21:06 <@matches> I think Wu admits that
+21:06 <@matches> Hmm, that is interesting
+21:11 <@matches> Argh that blog is all like "We should use web based documents instead of PDF"
+21:11 <@matches> Pixels or Perish detected
+21:11 <@matches> To be fair it does actually look nice
+21:14 <@matches> The table of contents in the black book are quite amusing
+21:14 <@matches> No! I finished writing about graphics stuff I need to do floating stuff
+21:15 < sulix> It's a brilliant book, but possibly for another day.
+21:16 <@matches> Dammit I guess I do need to produce more figures
+21:16 <@matches> Sigh
+21:17 <@matches> A picture is worth a thousand words and all that
+21:17 <@matches> And therefore takes at least as long as writing a thousand words to make
+21:27 <@matches> The more I look at SVG files the more convinced I am that they are actually the write way to do things
+21:27 <@matches> right
+21:28 <@matches> Despite all that philosophical guff, you can do the same things as postscript in similar ways, but you also have a DOM that isn't terrifying like whatever PDF supposely does
+21:28 <@matches> I guess PDF would be more efficient though
+21:29 < sulix> That's pretty much the conclusion I've come to.
+21:31 <@matches> Unfortunately now I know more about SVG I keep hand editing my figures
+21:32 <@matches> I don't need to use gnuplot's terrible data point markers anymore!
+21:32 <@matches> I am free!
+21:40 <@matches> I particularly like
+21:40 <@matches> That I can make the points have alpha now
+21:40 <@matches> So if you plot overlapping points it is no longer impossible to see them
+21:40 <@matches> Of course we are restricted by the zoom in the pdf viewer...
+21:41 <@matches> This project is too meta
+21:41 <@matches> It is doing my head in
+--- Day changed Fri May 23 2014
+11:22 < sulix> Welp. Submitting this version: http://davidgow.net/stuff/LitReviewDavid.pdf
+11:23 < sulix> (The introduction has only got more over the top, I'm afraid)
+11:48 < sulix> Do you know what is happening/isn't happening RE: Revised project proposals?
+12:03 < sulix> Well: Literature review is submitted.
+12:03 < sulix> (In person to the coordinator, which is a little bit scary)
+--- Day changed Sun May 25 2014
+15:42 <@matches> No meeting tomorrow by the way
+15:43 < sulix> Ah. Cool. I have like 300 things to do.
+15:43 < sulix> Just pushed fixes for all of the compile warnings, btw.
+15:43 <@matches> Cool
+15:44 <@matches> I want to keep editing my Lit Review :S
+15:44 < sulix> I had thought that Float() always returns a "float", but it sometimes returns a double.
+15:44 <@matches> Oh
+15:44 <@matches> Whoops
+15:44 <@matches> Well a double is technically still a float...
+15:44 < sulix> (Also, it turns out OpenGL actualy breaks the C++ spec, and is therefore impossible to use without hacks if you have -Werror enabled)
+15:45 <@matches> Sigh
+15:45 < sulix> It was warning that I was losing precision from float x = Float(blah);
+15:45 <@matches> One of the things I want to put in my lit review is a snarky paragraph about how no one actually obeys standards anyway
+15:46 < sulix> There are points where you get function pointers as void* pointers, but C++ needs to work on systems where code and data are stored in different bits of memory with different size pointers.
+15:46 <@matches> On the other hand no matter how much better I make the lit review no one will read it because I'm being assessed on a conference paper not a dissertation
+15:46 <@matches> Ah
+15:46 < sulix> So casting any data pointer to a function pointer is apparently illegal.
+15:47 <@matches> That's annoying
+15:47 < sulix> Fortunately, gcc doesn't complain if you start the line that does it with "__extension__", so that's what we do.
+15:47 <@matches> Haha
+15:54 <@matches> Ok I am still about 3 days behind on sleep but I guess I should do work
+15:54 <@matches> Bye
+--- Day changed Tue May 27 2014
+12:49 <@matches> We missed the Computable Document Format (CDF) by Mathematica by the way
+12:49 <@matches> Wolfram would be offended
+12:50 * matches hopes none of the Mathematica fanatics read the lit review
+12:50 <@matches> Or this channel
+12:54 <@matches> I did have both Mathematica and IPython as a dot point and they got the mighty question mark of confusion over them
+12:54 <@matches> Maybe I'll add them in later
+12:55 <@matches> Frames does not seem to agree with my assertion that practically anything can be considered a document format :P
+12:55 <@matches> Plain text!
+12:57 <@matches> So I was looking through last year's Mech/Chem final year conference
+12:57 <@matches> Naturally there is nothing remotely like this project in there
+12:57 <@matches> :(
+--- Log opened Tue Jun 10 13:59:54 2014
+13:59 -!- Irssi: #ipdf: Total of 2 nicks [1 ops, 0 halfops, 0 voices, 1 normal]
+13:59 -!- Irssi: Join to #ipdf was synced in 3 secs
+16:29 -!- mode/#ipdf [+o matches] by OperServ
+--- Day changed Wed Jun 11 2014
+13:13 <@matches> JVB just asked me if it was possible to have a self updating pdf
+13:13 <@matches> I suppose he didn't ask whether it would be easy
+13:15 <@matches> As in, one that would download itself if there was a newer version
+13:16 <@matches> Technically with the crippled PostScript it would be "No" but with all that stuff in the standard about DRM and "Action Objects" and Javascript and stuff...
+13:18 <@matches> Hmm, a webserver running git and a cronjob and requiring authentication may solve his problem
+13:18 <@matches> With pdf.js or just relying on browsers to have pdf plugins
+13:18 <@matches> Wait why am I solving JVB's problem
+--- Day changed Fri Jun 13 2014
+16:31 <@matches> So exams have finished
+16:31 <@matches> Well my exams have finished
+16:32 <@matches> Now I can go back to panicking about the project again
+16:37 <@sulix> Excellent: it's your turn to do something impressive for the meeting on Monday, then. :P
+--- Day changed Mon Jun 16 2014
+14:49 <@matches> Some of this OpenGL stuff doesn't quite add up
+14:49 <@matches> Like m_cahed_display.UnBind(); m_cached_display.Blit();
+14:50 <@matches> Oh
+14:50 <@matches> I see
+14:50 <@matches> There is a difference
+14:51 * matches -> OpenGL documentation
+14:53 <@matches> Right I see
+15:03 <@matches> Well, this makes a lot more sense than tpg's "Adventures in VEMS" in #ucc at least
+15:18 <@sulix> Well that's an achievement, I guess.
+15:18 <@sulix> Also http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2431.pdf
+15:18 <@sulix> It's the spec for "nullptr"...
+15:20 <@matches> "Pointers are pretty cool. Pointers that are NULL are pretty cool. We address these issues by proposing nullptr" ?
+15:21 <@sulix> Haha: Pretty much.
+15:22 <@matches> Why not just reserve the word "null"
+15:22 <@matches> I could get behind it then
+15:23 <@matches> It is not a null reference
+15:23 <@matches> But if you ever have a null reference something is horrifyingly wrong
+15:23 <@matches> Bah humbug
+15:24 <@sulix> They have a page about that where they said "everyone was naming their variables \"null\"".
+15:24 * sulix realises he just escaped those quote. Oh dear.
+15:24 <@matches> A valid point, which should have lead to "Everyone are morons"
+15:24 <@matches> Fun fact
+15:25 <@matches> Matlab (like fortran actually) will let you use key words as variable names.
+15:25 <@sulix> "It's a feature!"
+15:25 <@matches> Question on CITS2401 exam: "Why is 'ii' preferred over 'i' and 'jj' over 'j' for loop iteration?"
+15:26 <@matches> Both i and j are the complex number sqrt(-1)
+15:27 <@matches> It seems like naming it 'nullptr' instead of 'null' missed an opportunity to stop people naming their variables really confusing things :P
+15:30 <@matches> Well I am infinitely wiser about nullptr now but I don't think it will stop me just using NULL
+16:15 <@matches> This is slowly starting to make sense
+16:35 <@matches> I'm having a bit of difficulty because it's all so optimised for the GPU
+16:35 <@matches> I think what we need is an ObjectRenderer class or similar
+16:36 <@matches> Have one for each type of object and implement RenderUsingGPU and RenderUsingCPU
+16:36 <@matches> I will see what monstrosity I can come up with
+16:36 <@matches> But a lot of that code for the circles and rectangles is exactly the same just copied and pasted with different variable names
+16:37 <@matches> I think there is an official software engineering term for that sort of thing...
+16:46 <@matches> Alright, breaking everything
+16:46 <@matches> This will probably take a while
+16:47 * matches dreads merges
+17:02 <@sulix> Yeah, I was going to basically end up with an ObjectRenderer class, too.
+17:02 <@sulix> So I'll leave it to you for now and procrasinate from doing my maths in some other way.
+17:07 <@matches> Cool :)
+17:52 <@matches> Now I'm not very strict about the whole RAII thing myself, but there seem to be some cases where things can probably just go in the constructor?
+17:52 <@matches> I guess we can fight about those later
+17:54 <@matches> I guess I can see us wanting to set m_render_inited to false and have it automatically recreate everything, maybe, but I can't see a case where we will want to recompile the shaders, so I am going to put the shader initialisation in the constructors
+17:54 <@matches> I have gone mad with power
+17:54 <@matches> Maaad
+20:30 <@matches> This ObjectRenderer is like a two headed hydra
+20:31 <@matches> I thought about using just the ibo and vbo and getting the indices out of it, but that's a bit terrible
+20:31 <@matches> So it will have an ibo for the GPU and an array for the CPU
+20:35 * sulix thinks this makes sense.
+21:47 <@matches> Good news! I have things on the screen. Bad news. They are still on the GPU and they are wrong.
+21:49 <@matches> More coffee required...
+21:58 <@matches> Not sure if code wrong or fglrx having an existential crisis
+22:04 <@matches> Unrelated to the segfaults of doom, but I just realised that there's all this interest in using GPUs for scientific computation, and everything seems to point to them having vastly inferior floating point computation to a CPU, which is a bit disconcerting
+22:05 <@matches> I imagine the OpenCL libraries etc actually use the IEEE floating point capabilities? I hope?
+22:05 * matches files under "beyond the scope of project"
+22:06 <@sulix> If you commit code I can test it on non-fglrx if that'll help.
+22:06 <@matches> I'd rather not commit it just yet, I am 90% sure it is something I have done wrong and don't want to shame myself by committing broken code
+22:06 <@matches> It'd be like vomiting all over the codebase
+22:07 * sulix is pretty sure half of his commits broke something.
+22:29 <@matches> Ok I committed stuff that should in theory work with the test pattern again
+22:30 <@matches> Using new and improved ObjectRenderer classes
+22:30 <@matches> For some definition of improved
+22:30 <@matches> It doesn't actually use the CPU yet
+22:30 <@matches> It'll get there
+22:33 <@matches> You can go and add your MandleBrotSetRenderer now though :P
+22:36 <@sulix> Cool.
+22:37 <@sulix> The circles do trigger that intel driver bug again, though...
+22:38 <@matches> Ah damn
+22:38 <@matches> Would making CIRCLE_FILLED the first ObjectType fix that?
+22:38 <@sulix> It does.
+22:38 <@sulix> (I just checked)
+22:38 <@sulix> Yay intel!
+22:39 <@matches> Haha
+22:49 <@matches> Hey, does our rendering approach completely break compositing?
+22:49 <@matches> Render all circles
+22:49 <@matches> Then render all rectangles...
+22:49 <@matches> There's no depth...
+22:49 <@sulix> Um, maybe.
+22:49 <@matches> :P
+22:49 <@matches> I was just worrying about how to make compositing work using the CPU
+22:49 <@matches> and then I realised it won't work using the GPU as it is either
+22:50 <@sulix> If we're not doing alpha-blending, we could just add a z-coordinate and use the z-buffer.
+22:50 <@sulix> Otherwise, they need to be sorted if they intersect.
+22:50 <@matches> Let's not worry about this for now...
+22:50 <@matches> Even though I spent a rather significant part of my lit review explaining how awesome compositing is
+22:51 <@matches> I guess it doesn't matter, clearly the lit review was not intended for anyone to actually read
+23:42 <@matches> I suspect RenderPixels doesn't work
+23:45 <@sulix> This may be the case.
+--- Day changed Tue Jun 17 2014
+01:05 <@matches> Behold the magnificence of CPU based rendering
+01:06 <@matches> In which we pass a massive pixel array to the ObjectRenderer's and just save it to a BMP
+01:06 <@matches> Because OpenGL
+01:06 <@matches> I'll probably fix it later
+01:11 <@matches> Whoops seg faults ahoy
+01:12 <@matches> Wait I swear it wasn't segfaulting before I commited that
+01:19 <@matches> It segfaults sometimes depending on where you have the view. If you just have one circle and zoom in you can see the amazingly less jagged looking lines.
+01:19 <@matches> That, is a certified result
+10:13 <@sulix> I got the CPU rendered version to show up on the screen.
+10:14 <@sulix> RenderPixels was pretty broken.
+10:38 <@matches> Nice
+10:39 <@sulix> I think the segfaults are it trying to draw outside of the display.
+10:39 <@matches> Yeah
+10:39 <@sulix> I haven't managed to zoom in too much yet.
+10:39 <@matches> My clipping is probably wrongish
+10:40 <@matches> fonttex_frag.glsl? Fear
+10:40 <@sulix> Yeah, the "basictex_frag" file did a bunch of pretty font-specific things.
+10:40 <@matches> Ah
+10:43 <@sulix> The CPU renderer also shows some random lines when there are no outlines on the screen.
+10:43 <@matches> Is it just me or does it look slightly nicer on the CPU when zoomed out a bit
+10:44 <@matches> Well it looks different
+10:44 <@matches> I can't quite work out whether it looks nicer or worse :P
+10:44 <@sulix> Okay, it doesn't segfault if the rectangle outlines are disabled.
+10:45 <@matches> Ah
+10:45 <@matches> Yeah it is setting top/bottom/left/right outside the pixels
+10:45 <@sulix> I think there are just some slightly different edge-case rules when zoomed out.
+10:47 <@matches> With my skills at writing renderers I should be working on the fglrx drivers
+10:47 <@matches> :P
+10:47 <@sulix> Things vanish if you zoom in too much, too.
+10:48 <@matches> Blame it on floats
+10:49 <@matches> The CPU renderer is using a width of 1 pixel less than it should be
+10:49 <@sulix> Why are the floats sinking? :P
+10:49 <@matches> That's unrelated
+10:49 <@matches> It's probably an integer rounding issue somewhere
+10:49 <@matches> When the view gets big something goes to zero
+10:50 <@matches> The CPU renderer transforms everything to pixel positions and then renders using those
+11:02 <@matches> The GPU renderer occassionally leaves off the corners of things
+11:02 <@matches> I never noticed before
+11:02 <@matches> Anyway I think the segfaults are fixed
+11:03 <@matches> Looking at the mysterious disappearances next
+11:04 <@matches> It's integer overflow!
+11:04 <@matches> Facepalm
+11:05 <@sulix> Is it int64_t time?
+11:05 <@sulix> Or magic huge bigint time?
+11:05 <@matches> No I don't think that's necessary
+11:06 <@matches> If the transformed width is smaller or larger than the width of the screen you can surely just ignore it
+11:06 <@matches> Well, depending on what you are drawing
+11:08 <@matches> Well it does matter unless you do some clever maths
+11:08 <@matches> The clever maths was your part of the project...
+11:09 <@matches> So I will just make them int64_t for now
+11:50 <@matches> Pushe
+11:50 <@matches> *d
+11:50 <@matches> I should probably just make all the coorinates into Real instead of int64_t actually
+12:03 <@sulix> Wow: this is pretty awesome.
+12:03 <@sulix> I still get the artefacts, but I have to zoom in a lot more.
+12:03 <@matches> Haha
+12:04 <@sulix> Also, the CPU rendering artefacts and the GPU rendering artefacts are pretty similar on my machine, so it looks like it's just precision causing them.
+12:04 <@matches> That is nice
+15:20 <@matches> I'm trying to do a performance graph. Gnuplot doesn't like it much
+15:20 <@matches> Well actually it's python's crappy interface to gnuplot that doesn't like it
+15:23 <@matches> ... tempted to implement the performance graph in ipdf...
+15:23 <@matches> Just keep adding circles to the document
+15:24 <@matches> So meta
+15:25 <@matches> We need a cool performance graph-y thing
+15:26 <@matches> I think doing it in OpenGL is going to be the least shitty way actually
+15:26 <@matches> This is a wheel that's probably been invented but it was invented wrong
+17:11 <@matches> I've got a performance graph sort of working
+17:11 <@matches> It almost looks like we are doing real science!
+17:13 <@matches> I think we'll need to put some effort into our data analysis though because it's extremely noisy
+17:13 <@matches> Smoothing averages or something
+17:13 <@matches> Smoothing averages are the best
+17:14 <@matches> They make any data look amazing
+17:15 <@matches> Anyway, CPU rendering is only worse than GPU rendering when you force re-rendering
+17:16 <@matches> So well done with the amazingly efficient cached frame buffer
+17:18 <@matches> We can probably make it draw every frame both on the CPU and GPU to compare them in real time
+17:18 <@matches> The possibilities are limitless!
+17:19 <@matches> Graphs graphs graphs!
+17:20 <@matches> Also I did end up using Gnuplot and python (sorry) but I made it slightly less shitty
+17:27 <@matches> I have pushed things
+17:27 <@matches> Also we probably don't need all three of those ways to measure performance
+21:00 <@sulix> I got the graphs working on my laptop: very nice.
+21:00 <@sulix> I can see how more GPU time is used with GPU rendering and more CPU time with CPU rendering quite well, actually.
+21:59 <@matches> So the objects all being in one structure of arrays is sort of inconvenient because the size of objects has to be constant
+21:59 <@matches> Also the size of Real has to be constant
+22:03 <@matches> I guess we could have union {Rect rect, Bezier bezier} and do rectangles and Beziers in the same thing but that is slightly terrifying
+22:04 <@matches> But there's still the problem of Real because as soon as Real becomes arbitrary precision it will start allocating memory and not be fwrite/fread'able
+22:04 <@matches> :S
+22:05 <@matches> You'll still want the struct of arrays because that will make view reparenting much easier
+22:05 <@matches> Gah
+22:06 <@sulix> I'm tempted to just split it by type: Have an array of Rects, an array of Béziers, an array of Circles, etc.
+22:06 <@matches> Yeah but you need to store an "indexes" array as well
+22:06 <@matches> But that might be the least terrible
+22:07 <@matches> Yes that should work
+22:07 <@matches> Our fwrite/fread is still doomed though
+22:07 <@matches> When shit gets Real
+22:07 <@sulix> Yeah, you'd need some indices one way or another.
+22:08 <@sulix> And yeah, we'll need a massive "ConvertWhateverRealIsStoredInTheFileToWhateverRealIsDefined" function or something.
+22:08 <@matches> That will totally be its name
+22:08 <@sulix> (Some old compilers had function name limits... I wonder if modern gcc has)
+22:09 <@sulix> (There is but one way to find out!)
+22:09 <@matches> We don't need an array of circles/ellipses since we get those for free with Rect. Unless you want circular arcs as well as bezier curves
+22:10 <@matches> Which you probably will? So you can approximate beziers
+22:10 <@matches> Anyway I'll worry about adding Beziers first and once we've worked that out others should hopefully be easier
+22:11 <@matches> I was sort of thinking it would be good to be able to define groups of objects as a special object type
+22:11 <@matches> Then you can make paths out of your beziers
+22:11 <@matches> But they won't be fixed size
+22:12 <@matches> Anyway I will see if you have magically solved the problem for me in the morning :P
+22:14 <@sulix> I wouldn't count on it...
+--- Day changed Wed Jun 18 2014
+16:50 <@matches> Behold, the glory of Beziers and Bresenham!
+16:50 <@matches> Breseniers I shall call them
+16:54 <@matches> I'm getting a very strong vibe of "Reinventing graphics technologies from the 1990s" at the moment
+16:55 <@matches> I should probably look at floating point some more
+16:55 <@matches> And reinvent numerical computation technologies from the 1980s
+16:56 <@matches> We need a GPU renderer for the Beziers, and we need to fix save/load to not assume everything is a fixed size, and ...
+16:56 <@matches> Argh
+16:56 <@matches> All the things
+17:00 <@matches> Maybe I'll multithread the CPU rendering too, just to make things more difficult :P
+22:48 <@sulix> So I got some béziers rendering on the GPU.
+22:48 <@sulix> They're not the ones in the document, and they're not in the right spots, though.
+23:12 <@sulix> First 3 béziers are rendering properly on the GPU, then we get corrupted memory or something.
+23:14 <@sulix> Ah: I see, I need some way of uploading which bézier IDs are being used.
+23:41 <@sulix> Okay, Béziers now render on the GPU as well.
+23:43 <@sulix> The code is a little bit ugly, and for that I am sorry, but blame the fact that the GL feature that makes this nice is only about a year old and so nothing supports it.
+23:43 <@sulix> So we're basically uploading all of the raw document data into a huge texture.
+23:47 <@sulix> (If you ask me, the GPU ones also look slightly nicer, though that's probably a bug)
+--- Day changed Thu Jun 19 2014
+13:55 <@matches> From those papers I was under the impression just rendering a bezier on a GPU was an impressive feat, so well done :P
+13:57 <@sulix> (It's basically just a direct port of your CPU implementation, tbh)
+13:59 <@matches> When I zoom out the GPU ones look nicer, there's probably something wrong with my Bresenham implementation
+13:59 <@matches> Although it was mostly shamelessly copied from "Computer Graphics"
+13:59 <@matches> Except they were like "Here it is for 0 < m < 1, the rest can be done by symmetry"
+14:02 <@matches> The lines definitely have gaps on the CPU, and they also seem too thick as you zoom out
+14:02 <@matches> Having said that, I don't think the GPU starts at x0,y0
+14:03 <@matches> Anyway I'm going to implement a Rational number type and see if anything exciting happens (that's how you do research right?)
+14:06 <@matches> Fortunately I sort of did most of this for one of the codejam problems (where it turned out I didn't really need Rational numbers but I thought I did)
+14:20 <@sulix> Fixed the missing bit off the end.
+16:43 <@matches> I suspect Rationals are either not a very good idea, or there is a bug in one of my fundamental operations
+16:43 <@matches> +, -, *, / are hard
+16:56 <@sulix> Is it at least a pretty bug?
+16:59 <@matches> Um...
+16:59 <@matches> No
+17:00 <@matches> It seems buggy for anything other than the {0,0,1,1} starting view
+17:14 <@matches> I suspect it's the expf in the mouse wheel scrolling
+17:14 <@matches> Since you know, exp is definitely not a rational number...
+17:15 <@matches> Hmm, but it shouldn't matter because it will just convert to the nearest rational number
+17:16 <@matches> ie: p = (int64_t)(whatever*1e10) q = (int64_t)1e10
+17:28 <@matches> Oh
+17:28 <@matches> Oh
+17:28 <@matches> Head -> Desk
+17:28 <@matches> Rational & operator*=(const Rational & r) {this->operator=(*this*r); return *this;}
+17:28 <@matches> Rational & operator/=(const Rational & r) {this->operator=(*this*r); return *this;}
+17:29 <@matches> Rational & operator-=(const Rational & r) {this->operator=(*this+r); return *this;}
+17:29 <@matches> I think the worst part is that I actually said "It is probably a bug in my +,-,*,/
+17:29 <@matches> And it still took me this long to notice
+17:30 <@matches> The second worst thing is I've made that sort of mistake like 1000 times before
+17:30 <@matches> The third worst thing is I am recalling that article where the guy says "At least plus and times are sort of the same thing"
+17:30 <@sulix> Feel the power of copy and paste flowing through you.
+17:32 <@matches> Well let's not celebrate just yet, the view still goes to shit. Just slightly slower :P
+17:33 -!- matches changed the topic of #ipdf to: NaNpdf
+17:33 <@matches> Our document supports a view of {-inf,-inf,nan,nan} thus making it truly infinite precision
+17:34 <@sulix> I had that happen a lot when I was writing the original zoom code.
+18:19 <@matches> So I suspect that Rationals are just a really shitty number representation :P
+18:20 <@matches> Specifically, you get integer overflows really really fast
+18:20 <@matches> And if you are going to have a Rational that's BigInt / BigInt you may as well just have a BigFloat
+18:21 <@matches> The ancients were probably right.
+18:21 <@matches> When they decided not to use rationals.
+18:23 <@matches> I guess floats are rationals technically, I mean the representation using P/Q
+18:23 <@matches> I kind of wish I'd done some pure maths here...
+18:23 <@matches> Or paid more attention in second year
+18:28 <@matches> At least I sort of have conclusive evidence that rationals suck. As opposed to "it should be obvious to anyone with half a brain"
+19:00 <@sulix> Floats are not rationals.
+19:00 <@sulix> Not exactly.
+19:01 <@sulix> Something which can be stored in a finite amount of space as a rational cannot always be stored in a finite amount of space as a float, but not vice-versa.
+19:01 <@sulix> e.g.: 1/3
+19:04 <@sulix> Basically floats = rationals where the denominator must be a power of two.
+19:05 <@sulix> (Of course, these are all the same in the limit, but the limit of a cauchy sequence of rationals gives the reals, so the point is kinda moot, there, anyway)
+19:18 <@matches> Yeah floats are a subset of the rationals I think I meant
+--- Day changed Sat Jun 21 2014
+16:22 <@matches> So I got a new smartphone today... I'm having fun trying to zoom in on things
+16:24 <@matches> Actually the zooming isn't annoying so much as the needing to pan around to view all the text in a pdf
+16:25 <@matches> This is what I get for buying the cheapest phone with the lowest resolution they had :P
+16:26 <@matches> I didn't want to get one more expensive than my old one because I'm still convinced I will get around to fixing it one of these days
+16:26 <@matches> Or months. Or years. But eventually.
+--- Day changed Mon Jun 23 2014
+11:51 <@matches> The meeting happened at ~11:30
+12:49 <@sulix> Oh damn. I thought there wasn't going to be one today.
+12:49 <@sulix> What did I miss?
+13:04 <@matches> Basically I told him what we'd done
+13:05 <@matches> Which was rendering on CPU or GPU, and Beziers (but only degree 2)
+13:06 <@matches> And I implemented Rationals but they are terrible, so he sent me some code from an ACM competition about approximating things with Rationals
+13:13 <@sulix> Some javascript guy is trying to convince people that the only numeric data type should be some custom 64-bit decimal thing.
+13:13 <@sulix> A lot of people have started quoting Kahan at him.
+13:20 <@matches> Haha
+--- Log closed Tue Jun 24 16:07:29 2014
+--- Log opened Tue Jun 24 16:17:39 2014
+16:17 -!- Irssi: #ipdf: Total of 2 nicks [1 ops, 0 halfops, 0 voices, 1 normal]
+16:17 -!- Irssi: Join to #ipdf was synced in 15 secs
+--- Day changed Wed Jun 25 2014
+21:41 < matches> So... if we need to put a HTTP server in IPDF I've got us covered...
+21:44 <@sulix> You terrify me.
+21:45 < matches> I still have to work out Websockets
+21:45 < matches> They are silly
+21:46 <@sulix> I take it they aren't compatible with regular sockets.
+21:46 < matches> Well you use a TCP socket, but they aren't just plain text
+21:46 < matches> There's a protocol on top of it
+21:46 < matches> It's wired
+21:47 < matches> *wierd
+21:47 < matches> There are frames and things
+21:47 < matches> And copious amounts of base64 encoding the SHA1 hash of a string prepended to a magic string
+21:48 < matches> Apparently this makes it more secure
+21:48 * sulix looks doubtful.
+21:48 <@sulix> I could understand it being more secure if they actually encrypted things.
+21:48 < matches> They have wss:// as well which is just the same thing through ssl
+21:48 < matches> Yes it doesn't make sense
+21:49 <@sulix> But plain "boring" TCP has been used since (I am assured) the beginning of time and there are still one or two things that use it which are not currently being hacked into.
+21:49 < matches> Haha
+21:49 < matches> I'd like websockets so I can control my robot via my phone through its web browser...
+21:50 < matches> I can probably do that without websockets but it will also be useful for humphrey the rabbit
+21:50 <@sulix> Surely with plain old TCP you could control your robot via telnet, which is more awesome and just as user friendly.
+21:51 < matches> :P
+21:51 < matches> It will have a webcam image though
+21:51 * sulix mutters "ASCII art" under his breath.
+21:52 < matches> I figure if I implement everything in C++ it will be less "Webby"
+21:52 < matches> And more segfaultastic
+21:52 * sulix has a new favourite word.
+--- Day changed Thu Jun 26 2014
+14:58 < matches> I think the WebSocket RFC put this "Framing" business in just to confuse people
+14:58 < matches> My RFC Compliant* WebSocket server just sends the entire message in a single frame
+14:59 < matches> Doesn't TCP already do framing or something
+15:00 < matches> I mean, they specifically allow for frames with up to 2^63 bytes
+15:00 < matches> Sorry, bits not bytes
+15:02 < matches> So server -> client is pretty much TCP but you stick some stupid frame guff on the message
+15:02 < matches> client -> server involves... "masking"
+15:02 < matches> There are several long paragraphs on it
+15:10 < matches> I'm going to pretend this is related to precision
+--- Day changed Wed Jul 02 2014
+17:30 < matches> I put the code repository on github
+17:32 < matches> This is where a more hip and cool person would say something like "#yolo" but I prefer to wonder how I got 26K of lines and you have 65K...
+17:32 < matches> "How many lines of code does it take to draw a rectangle?" 91000
+--- Day changed Fri Jul 04 2014
+12:59 < matches> Found my rational bug
+13:00 < matches> ...
+13:00 < matches> Copy paste strikes again
+13:00 < matches> My operator/ looked suspiciously similar to operator+ -_-
+13:00 < matches> -____-
+13:02 < matches> Not sure how it got like that, it was definitely working at one point
+13:02 * matches should probably use git properly
+13:12 < matches> Pushed it
+13:21 < matches> So yeah, it should work fine until you zoom
+13:21 < matches> Then crazy things happen
+16:44 < matches> I think all the references you added at the last minute break my litreview
+16:45 < matches> (he says several months later :P_
+21:00 <@sulix> Question: in Rational::Simplify(), why is (-P)/(-Q) becoming (-P)/(Q) rather than P/Q?
+21:01 <@sulix> Shouldn't P = -P here? http://git.ucc.asn.au/?p=ipdf/code.git;a=blob;f=src/rational.h;h=41cce09078b4e96eb17a6bb6e28478ea64637b57;hb=HEAD#l74
+21:02 <@sulix> Also zoom can be improved (but not totally fixed) by reducing precision when overflow would be possible.
+21:19 < matches> Yeah, that's the idea of using the Stern Barcot tree Tim was talking about
+21:20 < matches> Which I still need to read about
+21:20 < matches> Also yes P should be -P because I am just that amazing at maths
+21:22 < matches> In other news assembly happened
+21:22 < matches> http://git.ucc.asn.au/?p=ipdf/code.git;a=blob;f=src/tests/add_digits.s
+21:22 < matches> Which no doubt has terrible bugs in it :P
+21:23 < matches> It was a bit confusing how passing and returning arguments with x64 was completely and utterly different from x86 and almost every tutorial is from at least ten years ago talking about x86
+21:24 < matches> x64 is actually much easier though
+21:25 < matches> At least, I think they are different, I didn't have to mess with the stack which seemed to be a thing with x86 and also that motorolla language we used in first year
+21:25 < matches> Just got all the arguments in a bunch of registers
+21:31 <@sulix> I think I just worked out why you have 16 "inc" instructions, and am loving it!
+21:32 <@sulix> inc doesn't change flags!
+21:32 < matches> I wonder if it would be faster to just store the carry flag in a register though
+21:33 < matches> Actually probably not because there'd be branches involved
+21:33 < matches> Hmm
+21:33 <@sulix> Traditionally, mucking about with flags is slow.
+21:33 < matches> Yep cool
+21:34 < matches> I've got the AMD64 ABI
+21:34 < matches> Chapter 2 is a good one
+21:34 < matches> "Software Installation"
+21:35 < matches> "This document does not specify how software must be installed on an AMD64 architecture machine"
+21:35 < matches> End chapter
+21:35 <@sulix> Just a thought, can use use the lea instruction instead of all of those incs.
+21:37 <@sulix> Like lea rsi, [rsi+8h]?
+21:37 * sulix ponders.
+21:38 < matches> Maybe, my assembly is very rusty and was based on those ELEC1301 labs in the first place...
+21:38 < matches> I don't even remember if they had lea
+21:39 <@sulix> (Also I just got a message from KDE: "could not launch a process. perhaps you have reached the limit of running processes")
+21:39 < matches> :S
+21:40 < matches> When did you last reboot?
+21:40 <@sulix> This morning, actually.
+21:40 < matches> Integer overflow in PID?
+21:40 <@sulix> It looks like it was an out-of-memory problem.
+21:40 <@sulix> On a related note, the intel instruction set documentation is a 3 and a half thousand page pdf.
+21:41 <@sulix> and firefox has a PDF viewer written in javascript.
+21:41 <@sulix> ...that runs by default.
+21:44 < matches> Hahaha
+21:44 < matches> Yes, pdf.js is apparently the best thing since sliced bread...
+21:45 < matches> I'm having some difficulty with lea, possibly the syntax
+21:47 < matches> "lea (%rsi+8), %rsi" is wrong
+21:48 <@sulix> Yeah, gcc's assembler uses whacked syntax.
+21:48 < matches> I thought it was just () instead of [], add % to all the registers, and swap destination and source
+21:48 <@sulix> http://git.ucc.asn.au/?p=ipdf/code.git;a=blob;f=src/tests/add_digits.s;hb=HEAD
+21:49 <@sulix> They replaced the arithmetic operators with strange things, too.
+21:49 < matches> Riight
+21:49 < matches> Thanks
+21:49 < matches> So 8(,%rdi,1) means [rdi+8]
+21:49 < matches> That is dumb
+21:49 <@sulix> I'm not sure if it's worth using nasm or the ".syntax intel" directive.
+21:51 < matches> Hopefully there won't be too much more assembly to write...
+21:51 <@sulix> Technichally lea (and other memory addressing instructions) take the form "[register+register*(1,2 or 4)+(number)]" in intel and "number(%register,%register,(1,2 or 4))"
+21:51 <@sulix> in gcc
+21:51 < matches> ok
+21:51 < matches> Well once I know the syntax I can cope with it
+21:51 < matches> But all the documentation being written in a different syntax doesn't help :P
+21:52 <@sulix> Yeah, there are a lot of people who hate gcc syntax, which was an (unsuccessful) attempt to make assembly for different machines more consistent)
+21:52 < matches> I decided to go with it because I vaguely remembered your commander keen patches looked like they were in gcc syntax :P
+21:53 <@sulix> Hah: they were in "ckpatch" syntax.
+21:53 <@sulix> And were just the final output bytes.
+21:53 < matches> The memory can play strange tricks...
+21:54 <@sulix> I used the "debug.com" utility that came with dos to assemble them, which let you write assembly to arbitrary memory.
+21:54 <@sulix> and then read the contents of that memory to see what it assembled down to.
+21:55 < matches> So, I need subtraction and multiplication but not division to implement arbitrary rationals
+21:55 < matches> I'll try sort those out tomorrow
+21:56 < matches> I'm pretty sure I'm doing better than at least one arbitrary integer representation
+21:56 < matches> Which had a int32_t word and int64_t "double" word
+21:56 < matches> So they could tell if they had a carry by doing the additions using double words
+21:57 < matches> The code in C was longer than add_digits is in assembly
+21:57 < matches> Although to be fair it might actually work on things that aren't amd64
+21:57 <@sulix> Well, the good news is that there's an "sbb" instruction like "adc"
+21:57 < matches> Excellent
+21:58 <@sulix> The bad news is that multiplication is harder.
+21:58 < matches> Yeah, at least I don't need division though
+21:59 < matches> Although converting it to a string will be annoying
+21:59 <@sulix> IIRC, the IMUL instruction gives an output twice as long as the inputs, to prevent overflow.
+22:00 <@sulix> Converting to a string won't be so bad if you get division done.
+22:00 <@sulix> And you can always just implement multiplication and division by slow recursive addition/subtraction.
+22:03 < matches> There's a bunch of papers on number representations that use things that aren't floats or rationals from a quick look
+22:04 < matches> I guess I just need to implement as many things as possible and compare them all
+22:04 < matches> Seems easy enough...
+22:04 < matches> (Famous last words)
+--- Day changed Sat Jul 05 2014
+11:09 < matches> Well... subtraction took me two seconds
+11:09 < matches> Should probably have just done it last night
+11:09 < matches> I got distracted
+11:09 < matches> By someone actually using my websocket library
+11:09 < matches> Does this mean I'm officially an open source developer now
+11:09 < matches> I didn't even give it a license :S
+11:11 < matches> Hmm
+11:12 < matches> Multiplication...
+11:12 < matches> It is tempting to just use a for loop and call the += operator...
+11:40 < matches> I'll do that for now I think
+11:41 < matches> Once += actually works
+11:41 < matches> Turns out I will definitely need division also
+11:42 < matches> I was looking at the rationals going "There are no divisions here!"
+11:42 < matches> But there are
+11:42 < matches> In the gcd
+11:42 < matches> Mind you maybe I don't need to call gcd if I have arbitrary integers :P
+11:42 < matches> Just use all the memory
+12:39 < matches> Ok for loop for multiplication is not easy
+12:39 < matches> Bah
+12:39 < matches> Having to actually learn assembly properly
+12:40 < matches> I mean I could use a for loop but it would have to use an Arbitrary integer and take a very long time...
+12:47 <@sulix> There's no need to have a for loop index > 64bit because there will never be enough memory for an integer that big.
+12:47 < matches> True
+12:54 < matches> Putting "_asm" in filenames so that our Makefile can do the .s files is kind of irritating
+12:54 < matches> Would naming them .cpp work? That would be even more irritating though!
+12:54 < matches> Oh well it compiles
+12:58 < matches> I bet it turns out 128 bit integers would have been more than sufficient for any zoom range people could feasibly get to by scrolling
+13:15 <@sulix> I'm told 256-bit integers can represent the visible universe to the width of a proton or something.
+13:45 < matches> I might put a maximum length in once this works
+13:45 < matches> So I'm not doing a Java
+13:46 < matches> Where 1/3 becomes "Runtime Exception!"
+13:46 < matches> That's with BigDouble not BigInt but whatever
+14:00 < matches> I must admit, assembly is pretty nice for this sort of thing
+14:00 < matches> At least, the inner operations
+14:00 < matches> Not for managing the memory
+15:29 < matches> Alright. We have an Arbint class that is equivelant to an int64_t when it only has one digit.
+15:30 < matches> I'm not sure how to test that extra digits function correctly
+15:30 < matches> Other than just looking at a few cases and going "Yep that looks right" :S
+16:40 < matches> Well... somewhere along the way I lost kcachegrind and now I seem to have to run dist-upgrade to get it back
+16:41 < matches> Currently 10% of the way through upgrading tex-live...
+16:41 < matches> The mystery of just how shitty the Arbints are will have to wait
+16:42 < matches> Well it's clear they are shitty but I suspect there is a bug in division
+16:42 < matches> Maybe I should actually read my code
+16:42 < matches> Blargh
+16:47 < matches> Ok constructing a rational takes infinite time
+16:51 < matches> Ah, 1 % 1 == 1
+16:51 < matches> That is definitely not correct :P
+17:56 < matches> Oh my goodness I just rendered a frame
+17:56 < matches> On the GPU...
+18:00 <@sulix> Hmm... {add,sub}_digits_asm.s are missing from git.
+18:05 < matches> Really
+18:05 < matches> Whoops
+18:07 < matches> There you go
+18:07 < matches> Addition, subtraction, multiplication should be fine, I need to actually do division properly
+18:08 < matches> Also probably pow at some point
+18:08 < matches> Since pow still just casts things to doubles
+18:22 <@sulix> It works!
+18:22 <@sulix> (Eventually)
+18:24 < matches> Haha
+18:24 < matches> Of course it's still in the single digit range
+18:24 < matches> Or did you manage to wait long enough to zoom a bit
+18:25 < matches> I'm sure I can make this division better if I use some kind of binary searchish type algorithgm
+18:25 < matches> I could look up the proper algorithm too I guess
+18:25 <@sulix> Yeah, I was thinking binary search.
+18:26 <@sulix> You'd want a decent bitshift implementation.
+20:32 < matches> Yeah it is more difficult than I thought
+20:33 < matches> I'm going to need "shift_digits" assembly functions
+20:33 < matches> C style bit shifting has too many wierd edge cases
+20:36 < matches> 0x7000000000000000 >> 3 == 0x0e00000000000000 ?
+20:36 < matches> There are more bits set in the second number than the first!
+20:38 < matches> And unlike multiplication where it fills an extra register for you, you just lose the extra bits with shr and shl :S
+20:39 < matches> Except for a carry
+20:39 < matches> So I'd have to do a loop one bit shift at a time
+20:39 < matches> Blergh
+20:40 < matches> I shall resume my epic battle with primary school level mathematics tomorrow
+--- Day changed Sun Jul 06 2014
+00:32 <@sulix> long division of an arbint by a uint64 worksish.
+09:47 <@sulix> long division of an arbint by a uint64 now actually works and is less obviously badly designed
+10:32 < matches> Thanks...
+10:33 < matches> In other news I seem to have broken X again
+10:34 <@sulix> Oh no!
+10:35 < matches> We need an ASCI renderer...
+10:36 <@sulix> That can not possibly end badly.
+10:40 < matches> shouldn't be too hard...
+10:40 < matches> Lets see if reinstalling fglrx works
+10:41 < matches> I need to add that to a boot script :S
+10:42 < matches> uhoh installation failed
+10:48 <@sulix> Hmm... enabling optimization makes Arbint segfault.
+10:49 < matches> You should probably make quadtrees
+10:50 < matches> Although I admit you're better at Arbints than me :P
+10:50 <@sulix> Yeah... I should.
+10:50 <@sulix> But segfaults...
+10:51 < matches> Yeah somewhere in std vector I had some as well
+10:51 < matches> I think I might change to a custom dynamic array
+10:52 < matches> Then fast copying is easier
+10:52 <@sulix> Yeah, it's segfaulting in std::swap somewhere, I think.
+10:52 < matches> I'll fix it when I have X
+10:53 < matches> Or an ascii renderer...
+10:54 < matches> Probably more realistic at this stage
+10:55 <@sulix> I'm pretty certain there's a unicode character for "face of disapproval due to fglrx bugginess".
+10:56 < matches> Yeah but when you try and render it you get a seg fault
+11:24 < matches> Woo, xvesa
+11:26 < matches> I see what you mean about fglrx being hard to remove
+11:58 <@sulix> So: quick profile. 98% of frame rendering time is spent in Arbint::Division.
+11:59 < matches> Yeah
+12:00 < matches> I *was* trying to install kcachegrind you know
+12:00 <@sulix> The vast majority of that time is spent in malloc and free.
+12:01 < matches> Well copy constructing an Arbint requires copy constructing the vector
+12:01 < matches> I'll investigate
+12:01 < matches> Now I have X again
+12:01 < matches> Go make a quad tree
+12:02 <@sulix> Also, should add_digits clear the carry flag at the beginning?
+12:02 < matches> Hmm
+12:02 < matches> Probably
+12:02 < matches> Yeah
+12:09 < matches> I suspect having a copy-on-write Arbint won't help as much as having a non-terrible division algorithm so I'll try fix that first
+12:09 < matches> But copy-on-write Arbint shouldn't be too hard
+12:09 < matches> Oh unless the original changes
+12:10 < matches> Yeah it would be hard
+12:10 < matches> I'm sure I did something like it before
+12:10 < matches> Back when I actually made my own data structures instead of just using std::vector
+12:15 <@sulix> My custom vector class: http://davidgow.net/stuff/DynamicArray.h
+12:15 <@sulix> Probably won't compile without a bunch of other files, though.
+12:16 < matches> I think I have several, in different versions of neurosis
+12:16 < matches> Which was never under git
+12:16 < matches> Some of them were prone to segfaults though
+12:17 < matches> So, will you have some kind of quad-tree-y thing by monday? :P
+12:17 <@sulix> Mine works, but doesn't call constructors or destructors, so it's only really useful for ints/floats/pointers or structs thereof.
+12:18 <@sulix> I have a "struct QuadTree".
+12:18 <@sulix> (You can't do anything with it, but the basic idea is there)
+12:20 < matches> My shifting operators might not have been as fith as I thought last night
+12:20 < matches> Since 7 and e do actually have the same number of bits
+12:21 < matches> I'm not sure where that came from
+12:21 < matches> Ah dammit
+12:21 < matches> Cannot find -lGL
+12:22 <@sulix> Try just removing that from the Makefile
+12:22 <@sulix> I think when I GL-3'd everything I made it load libGL at runtime.
+12:23 < matches> Well it will compile but I get glx errors
+12:23 < matches> I get similar errors running glxinfo though...
+12:24 < matches> Odd
+12:26 <@sulix> I think you still have some of fglrx breaking things.
+12:26 <@sulix> It replaces the system libGL.so
+12:26 < matches> I installed mesa's stuff
+12:27 <@sulix> You need to also get the version of libGL that runs as part of the X server, IIRC.
+12:28 < matches> I'll try some apt-get --reinstalls
+12:29 < matches> I think most of my problems were that debian was going "You don't have a graphics driver, here, have one" and then things were breaking and reinstalling fglrx would give me graphics but leave me with a partially installed debian driver as well :S
+12:30 < matches> Well ok
+12:30 < matches> most of my problems were fglrx
+12:30 <@sulix> I remain sceptical that installing fglrx by hand will ever cause anything that is not pain.
+12:30 < matches> Well it worked better than the open source drivers for a very long time
+12:30 < matches> It all ended in tears and segfaults though
+12:32 < matches> Also it worked better than the non-free fglrx package in the debian repos which always ended in tears and segfaults
+12:33 <@sulix> I use the non-free nvidia package, which works fine, even if it is horribly outdated.
+12:34 <@sulix> I'm scared of the sheer amount of ripping up the rendering code getting quadtrees working will take.
+12:39 < matches> Haha
+12:40 < matches> It might be easier to do the CPU rendering in quad trees first?
+12:40 < matches> I'm not quite sure how you'll do it
+12:41 < matches> CPU rendering at least gives you direct control over the rendering target as a pixel buffer
+12:41 < matches> GPU rendering is a bit shady (ho ho)
+12:41 <@sulix> ...
+12:42 <@sulix> That was terrible, yet accurate!
+12:42 < matches> With the CPU rendering we're already passing the objects list, view, and target bounds
+12:42 < matches> So maybe you can adapt View or something to be quad-tree-ish
+12:43 < matches> Good luck
+12:44 <@sulix> Yeah, the current plan is to adapt the rendering stuff to accept a "first object id" and "last object id", and then only render those.
+12:47 < matches> Hmm, you could call RenderUsingCPU with a different target pixel buffer for each part of your quad tree or something
+12:48 < matches> Oh well, hopefully I can adapt whatever you do into RenderUsingASCII :P
+12:49 < matches> I don't need GLX working to try and fix division but I'd really like to have GLX working
+12:49 < matches> Sigh
+13:12 < matches> I'm making progress, instead of reporting an invalid operation glxinfo segfaults now
+13:13 < matches> So I have the wrong libraries or something... how to get the right ones...
+13:32 <@sulix> Woo. I got it compiling again!
+13:32 <@sulix> And the rendering is only half-wrong.
+13:33 < matches> Nice
+13:33 < matches> Manually deleting anything on my system with fglrx in it...
+13:34 <@sulix> Someone really needs to write an "fglrx removal guide".
+13:34 < matches> I'm not sure why reinstalling the radeon driver and mesa isn't actually giving me a libGL
+13:34 < matches> At least
+13:34 < matches> I suspect it is just leaving the existing broken one
+13:36 <@sulix> So it turns out that *2 I don't understand is important.
+14:01 < matches> Ok
+14:01 < matches> I have glxgears
+14:01 < matches> An epic achievement
+14:01 < matches> I had to go back to fglrx but at least this time its the debian packaged version
+14:02 < matches> The radeon driver seems to work better for stuff that isn't glx
+14:03 < matches> Which is pretty cool but I kind of like glx actually working
+14:11 < matches> Ok... time to fix division
+14:11 < matches> Finally
+14:11 < matches> No wait time for coffee
+14:11 < matches> Then time to fix division
+14:24 < matches> Did you test the div_digits function at all?
+14:25 < matches> # We want to point to the end of the buffer (LSB)
+14:25 < matches> Aren't I doing it the other way around...
+14:25 < matches> I'll test it
+14:28 <@sulix> With long division you do things in the opposite direction to addition.
+14:29 <@sulix> I tested it with some simple things and it worked.
+14:34 < matches> Hmm
+16:35 < matches> Well the good news is that division is faster now
+16:35 <@sulix> Cool!
+16:36 < matches> The bad news is that I can't see anything
+16:36 < matches> Even when GPU rendering
+16:36 < matches> Also segfaults
+16:36 <@sulix> I've just pushed some initial quadtree-enabling breakage.
+16:36 < matches> I didn't work out how to apply the div_digits to a multi digit number either
+16:36 <@sulix> Yeah, I thought about that, then went to bed.
+16:36 < matches> I might convert the current algorithm which is all based on bit shifting
+16:36 < matches> To assembly
+16:37 < matches> But maybe not
+16:37 < matches> Actually being able to see something render would be good even if it were slow
+16:37 < matches> Then I can think about making it faster
+16:38 <@sulix> The old one had all of the beziers connected for no readily apparent reason.
+16:38 < matches> I have a tester called "Arbitrary Rationals" (arbrationals.cpp) which sounds like some kind of political party
+16:39 < matches> A rather indecisive political party
+16:39 <@sulix> That's amazing.
+16:48 < matches> Ah, I might be having trouble with the sign of things, hm
+16:49 < matches> Rational 15625/288230376151727369 (0.000000) is not close enough at representing 1.000000 (1.000000 vs 0.001000)
+16:49 < matches> That doesn't look like a sign problem...
+16:52 <@sulix> I admit, 15625/288230376151727369 is not really similar to 1.
+16:54 < matches> So, somewhere along the way Arbint(1e6) became 15625 and Arbint(1e6) also became 288230376151727369 ?
+16:54 < matches> Uninitialised things?
+16:54 < matches> Constructing from int64_t seems fine
+17:00 < matches> That amazing moment when it works perfectly and then you realise that's because you compiled with reals as doubles and not rationals
+17:00 <@sulix> Ha: I've done that a few times.
+17:19 < matches> Maybe I shouldn't have pulled your latest commit
+17:19 < matches> Now I have two problems :(
+17:22 < matches> Meeting tomorrow
+17:22 < matches> "So how much progress have you made?"
+17:22 < matches> "Segfaults are up 100% to a record high!"
+17:26 < matches> Oh ok
+17:26 < matches> I'm not sure if this is new
+17:26 < matches> But if there is nothing in the document the GPU rendering doesn't like it
+17:27 <@sulix> Hmmm... there might be some issues with that.
+17:28 < matches> Ok
+17:28 < matches> Rectangle renders
+17:28 < matches> With arbitrary rationals
+17:28 < matches> In the default view
+17:29 <@sulix> Ooh!
+17:31 < matches> I'm going to commit this even though it's totally broken
+17:32 <@sulix> Things being broken hasn't stopped me from committing them.
+17:35 < matches> I love this though
+17:35 < matches> When you activate CPU rendering
+17:36 < matches> You get like a billion errors from Rational<Arbint>::CheckAccuracy
+17:36 < matches> And then the Bezier appears!
+17:36 < matches> Magically!
+17:36 < matches> I guess I shouldn't rule out a bug in CheckAccuracy :P
+17:36 < matches> Although zooming will definitely cause a segfault
+17:38 <@sulix> I tried running the really slow version under valgrind, but that turned out to be a bad idea.
+17:39 < matches> I've pushed the slightly less really slow version
+17:39 < matches> That is still really slow
+17:39 < matches> I can't install kcachegrind
+17:39 < matches> It is really annoying
+17:40 < matches> There aren't any valgrind analysis things that don't require the entirity of KDE are there?
+17:40 < matches> Or should I just learn how to read the raw output files
+17:40 <@sulix> Cool: it works.
+17:41 <@sulix> (I dunno, I just use KDE :P)
+17:41 <@sulix> You can try "perf" or "oprofile".
+17:41 < matches> Well I can't even install KDE :S
+17:41 <@sulix> They're terminal-based.
+17:41 <@sulix> Well, perf is, at least. There's a gtk+ oprofile gui.
+17:41 <@sulix> They both measure the entire system by default though.
+17:43 <@sulix> Rational::Simplify is ~54% of time (w/ GPU rendering) with the new build, according to callgrind.
+17:50 < matches> I'm a little confused by some of the outputs of Rational::CheckAccuracy given that it does actually seem to render the bezier properly on the CPU
+17:50 < matches> I think the segfault might be related to my (ab)use of things like memcpy on std::vector::data()
+17:52 < matches> Also I think I've fixed my dependency hell
+17:52 < matches> Well
+17:53 < matches> Depending on how this turns out I will end up with the entirity of KDE hopefully including kcachegrind, or I will end up with no X again
+17:53 < matches> And much swearing will ensue
+17:54 <@sulix> Yeah, it segfaults immediately if you enable optimization level 2 or higher.
+17:55 < matches> Hm
+17:56 < matches> I'll probably get rid of std::vector then
+17:57 <@sulix> The problem I'm seeing is in the vector<Bezier>::push_back() bit, so who knows what is going on.
+17:58 < matches> Oh that's odd
+17:58 <@sulix> Okay, don't run it in valgrind.
+17:58 <@sulix> I'm getting about 200 "uninitialized values" a second in the nVidia driver.
+17:58 < matches> But I just installed kcachegrind!
+17:59 <@sulix> (Oh wait, that was with REAL=double)
+17:59 < matches> Haha
+18:00 < matches> Wait, vector<Bezier>::push_back causes problems even with REAL=double :S
+18:00 <@sulix> Nah, the nVidia driver seems to.
+18:01 <@sulix> I've now compiled again with REAL=5 and I'm getting a number of invalid reads off the end of the vector<digit_t> in GetBit()
+18:02 < matches> Division
+18:02 < matches> Oh
+18:02 < matches> oooh
+18:02 < matches> > -> >=
+18:02 < matches> ...
+18:03 <@sulix> Well, my first attempt to fix it just broke rendering.
+18:04 <@sulix> Ah, yep, I see it.
+18:05 < matches> I think I need to do less memcpy/memseting and more std::vector::operator= -_-
+18:05 < matches> I mean, they implemented it for a reason
+18:05 <@sulix> So, with that change it no longer segfaults!
+18:05 <@sulix> (It corrupts memory and throws an exception instead)
+18:05 < matches> Woah
+18:06 < matches> I changed Arbint operator= to use std::vector operator=
+18:06 < matches> And now I get a filled circle on top of my bezier...
+18:07 < matches> Ok, I will rewrite Arbint to just rely solely on std::vector operations
+18:08 < matches> That might slow it down but it's impossible to test that the maths works properly with all these memory errors
+18:09 <@sulix> Should you be using m_sign more often?
+18:09 <@sulix> It seems to be "forgotten" in a number of places...
+18:10 <@sulix> Hmm... everything looks like it's working at the moment, actually.
+18:10 < matches> What else did you change?
+18:10 < matches> Try zooming
+18:11 < matches> That will break it
+18:11 <@sulix> Zooming seemed to work, actually.
+18:11 < matches> Are you sure you compiled with REAL=5
+18:11 < matches> The sign is a bit wierd
+18:12 <@sulix> It works for a little bit, then the view bounds suddenly become huge.
+18:12 < matches> Haha
+18:12 <@sulix> For no reason, the y coordinate jumps to 10^8.
+18:13 <@sulix> Also after you've zoomed, sometimes translating goes in the wrong direction or is otherwise broken.
+18:15 < matches> That might be related to m_sign...
+18:15 < matches> The joys of implementing your own number representation
+18:16 <@sulix> Trying to "fix" the sign fixed zoom, but broke translation even more.
+18:18 <@sulix> Also: best representation of 1 ever: 9223372036854775807/9223372036854775807
+18:18 < matches> Hahaha
+18:18 < matches> Oh
+18:18 < matches> I think I commented out a Simplify() somewhere :P
+18:18 < matches> No
+18:18 < matches> I didn't
+18:18 < matches> Hmm
+18:19 < matches> Well I am going to push some minor changes
+18:20 <@sulix> Also: T g = gcd(T(llabs(P)),T(llabs(Q)));
+18:20 <@sulix> Is that "llabs" truncating everything?
+18:20 < matches> ...
+18:20 < matches> Probably
+18:20 < matches> !
+19:05 <@sulix> Well, my attempt to write a templated abs() function that worked for Arbint may have worked, but it crashed X before I could find out.
+19:05 <@sulix> I do not want to know how that is possible.
+19:05 < matches> Heh, I was trying to do that before dinner
+19:06 < matches> I just got segfaults
+19:08 < matches> Oh
+19:08 < matches> I see
+19:08 <@sulix> I suspect the best thing for me to do is to just stash all of my changes and break some more quadtrees.
+19:08 < matches> Yeah
+19:08 <@sulix> But first I'll have to get X working again.
+19:08 < matches> The problem with overriding llabs is that the constructor for Arbint calls llabs...
+19:08 < matches> And Arbint has a constructor from int64_t...
+19:09 < matches> So as soon as you implement llabs using Arbint it will call itself for eternity
+19:09 <@sulix> I made a new function called "real_abs" (because "i_went_to_the_gym_now_look_at_my_abs" was too long) and just used that.
+19:09 < matches> Bahaha
+19:10 <@sulix> Then X started using 100% of my CPU and nothing responds to anything.
+19:10 < matches> :S
+19:10 <@sulix> The mouse cursor still moves, but everything else is a black screen.
+19:11 <@sulix> Excellent, "sudo pkill -9 Xorg" has made everything work again.
+19:12 <@sulix> (And even fixed an unrelated problem, which is good but worrying)
+19:17 <@sulix> Note to self: if something crashes X when you run it once, don't run it again after fixing X.
+19:18 < matches> Haha
+19:18 <@sulix> Now to try it for a third time.
+19:18 < matches> I've got an abs working
+19:18 <@sulix> Ah, excellent.
+19:19 <@sulix> Does it make things better? Worse? The same but slower?
+19:19 <@sulix> Crash X?
+19:20 < matches> It doesn't crash X but I think I have an infinite loop in gcd now
+19:21 < matches> I should probably work out why X/X for really big X is not simplifying to 1/1
+19:43 < matches> So it turns out it's a pretty good idea to have a tester that actually tests lots of different numbers with every single operation
+19:43 < matches> As opposed to
+19:43 < matches> "1/2 == 0.5" yep looks good she'll be right
+19:43 < matches> One could say
+19:43 < matches> There are *signs* of serious problems
+19:44 * matches puts on sunglasses
+19:44 < matches> No wait I got the order wrong
+19:44 < matches> Oh well I wasn't cool enough to watch that show anyway
+20:18 < matches> So now I have a tester that actually tests things
+20:18 < matches> I just need to blindly fumble around with m_sign until all the tests are passed!
+20:18 < matches> Right?!
+20:26 < matches> Heh, it's amazing how many errors fixing the sign in Division prevents
+20:27 < matches> Well amazing until you realise that every single Rational calls a division at least once
+20:44 <@sulix> Hmmm... there seem to be a lot of cases where we get things becoming 1 (randomnumber/randomnumber) instead of what they should be, according to CheckAccuracy.
+20:46 < matches> Yeah
+20:46 < matches> It should work nicer nowish
+20:46 < matches> At least, the tester works most of the time...
+20:46 < matches> It still randomly fails sometimes
+20:46 <@sulix> Yeah, it's working much better.
+20:46 < matches> Now 12% of the time is in std::vector::size()
+20:46 <@sulix> All of the things I've seen have been to do with subtraction in ScaleAroundPoint()
+20:47 < matches> Ah
+20:47 < matches> Wait I haven't pushed the 12% in std::vector::size yet
+20:47 < matches> tl;dr I was allocating one extra digit every single addition operation and then deleting it if it wasn't used
+20:48 < matches> Because I am just that good :P
+20:48 < matches> I suspect the Arbint is going to break when it actually does need to resize itself
+20:49 < matches> But for now I will settle for "At least as good as an int64_t"
+20:49 < matches> * But slower
+20:49 <@sulix> I'm curious as to why digit_t is int64_t and not uint64_t.
+20:49 < matches> Oh it is uint64_t now
+20:49 < matches> It was int64_t mainly because geany doesn't syntax highlight uint64_t
+20:50 <@sulix> Ah.
+20:50 < matches> Then I realised being int64_t instead of uint64_t broke the shift operators
+20:50 < matches> Because they try to preserve the sign
+20:50 <@sulix> Shift on signed ints is undefined behaviour, IIRC.
+20:51 < matches> Yeah I was considering writing the shift in assembly but its easier to handle the underflow/overflow into the next digit in C
+20:52 < matches> Zooming is still incredibly slow
+20:54 < matches> In fact it is infinitely slow
+20:54 <@sulix> I once waited about 10 minutes and did get another frame.
+20:54 < matches> In fact the Arbint appears to want to grow an infinite number of 0L digits
+20:55 <@sulix> Ah ha! I have realised why CheckAccuracy is only throwing errors on "-".
+20:55 <@sulix> The CheckAccuracy calls for everything else have been commented out,
+20:55 < matches> They should all be commented out so I can use tests/realops.test instead
+20:57 < matches> 23 / 12000 operations failed... doesn't seem too bad...
+20:58 <@sulix> Keep in mind that == isn't precise as it casts to doubles.
+20:58 < matches> You get more like 40 out of Rational<int64_t>
+20:58 < matches> Yeah they are "equal" if it is within 1e-1 :S
+20:58 < matches> I'm searching for the more totally catastrophic failures like the wrong sign first :P
+21:20 < matches> Ok tomorrow I might just try using boost arbitrary integers or something
+21:28 <@sulix> All of the failures I'm getting are with "/="
+21:28 <@sulix> Except one, which was only just outside the error bounds, so probably the doubles' fault.
+21:30 < matches> I was restricting the test values somewhat though
+21:30 < matches> (With rand()%100 + 1)
+21:33 <@sulix> You do know that the Rational<Arbint> -> double conversion is totally broken if either P or Q have > 1 digit.
+21:33 < matches> Yeah I noticed that
+21:37 <@sulix> Oh man, re-enabling the operator double on Arbint totally breaks things.
+21:40 < matches> Yeah don't touch it
+21:40 < matches> Basically touching anything will totally break something else
+21:40 < matches> :S
+21:40 < matches> I should probably sleep some more before attempting to fix things
+21:40 <@sulix> The other bug I just found is that Arbint didn't have the unary "-" operator, so writing "-P" would silently cast to int64_t.
+21:41 < matches> Ah ok
+21:41 < matches> I thought unary - was equivelant to "0 - x" but I suppose that doesn't make sense
+21:41 <@sulix> Nah, it has to be written explicitly.
+21:44 <@sulix> Okay, I think I've got realops.test down to 0 errors with Arbint.
+21:45 < matches> Well you're doing better than me
+21:46 <@sulix> I'm running it with a huge number of tests now.
+21:47 <@sulix> 85.95% of my entire computer's processing time is in IPDF::Rational<IPDF::Arbint>::operator/=
+21:48 < matches> Can you push what you have?
+21:48 <@sulix> Yeah, I will in a second.
+21:48 <@sulix> It's basically a lot of hacks.
+21:49 <@sulix> CPU rendering is broken, though.
+21:49 < matches> There were cases where it would grow an infinite number of digits; did you fix those?
+21:49 <@sulix> Probably not: it still gets very, very slow zooming.
+21:51 < matches> Yeah there's something wrongish it shouldn't need extra digits so fast
+21:51 <@sulix> Pushed now.
+21:52 <@sulix> Now to look at the diff and see what I actually changed.
+21:53 < matches> Oh
+21:54 < matches> Simplify call in Rational operator= is good
+21:56 < matches> I think I fixed some more bugs but I also introduced an infinite loop so...
+21:57 < matches> How is the quad tree bit going :P
+21:57 <@sulix> Yeah, about that...
+21:58 < matches> Remember Arbints don't have to work for quad trees to work :P
+21:58 < matches> Or do they
+21:58 <@sulix> In theory, no.
+21:58 <@sulix> In practise, it probably depends on how one defines "success".
+21:59 < matches> I think we need to design a test pattern where you actually want to zoom forever
+21:59 <@sulix> Highly theoretically, I'm pretty certain the QuadTree basically ends up isomorphic to the Arbint.
+21:59 < matches> Seems legit
+21:59 < matches> Can you prove it?
+21:59 < matches> That would be a useful result
+21:59 <@sulix> Yes*
+22:00 <@sulix> *hopefully
+22:00 < matches> I'm afraid most of my "theory" is based solely on intuition at this point :S
+22:00 < matches> Well the division algorithm came from wikipedia but division isn't as intuitive as the other operations
+22:01 < matches> Actually if I can fix all these other stupid bugs I'll try my binary searchish division idea
+22:01 <@sulix> Yeah, I spent a while racking my brain for long division, and then only managing to work it out for dividing by a single digit.
+22:02 <@sulix> That's really, really easy in asm, as well, which is nice, but not quite as useful as I'd hoped.
+22:02 < matches> It's pretty useful; we can still have a "if div.m_digits.size() use the assembly function"
+22:02 < matches> * size() == 1 that is
+22:02 <@sulix> Wikipedia mentioned doing newton-raphson for division, which is a terrifying thought.
+22:02 < matches> Haha
+22:03 < matches> So I've got Arbint::Shrink() calls pretty much after every operation now for no apparent reason
+22:04 <@sulix> Does it help?
+22:05 < matches> On the 551st test Shrink has been called 4 times in a row and then something after that causes an infinite loop
+22:05 < matches> I can't work out what it is
+22:05 < matches> I have a GrowDigit that spams Debug messages now
+22:05 < matches> So its not that
+22:05 < matches> It's silent
+22:05 < matches> Let's see what callgrind has to say
+22:06 < matches> A few minutes should be enough for it to be obvious right
+22:07 < matches> I think the division loop runs forever
+22:07 < matches> Bugger
+22:08 < matches> Wait that doesn't make sense there's only 1 digit
+22:08 < matches> Blargh
+22:17 <@sulix> So using the asm version when possible makes realops.test 20x faster, but there were a couple of failed tests.
+22:18 <@sulix> I'm not sure if they're new or not, because I was able to run many more tests.
+22:20 <@sulix> Also, I think I've found your infinite loop.
+22:23 <@sulix> Okay, maybe I've just obfuscated the code some more.
+22:24 < matches> Infinite loop is due to subtraction bug
+22:24 < matches> I'm pretty sure
+22:24 <@sulix> Yeah, pushing a "fix"
+22:26 <@sulix> Pushed, but think I might have found a bug in the fix.
+22:26 < matches> Ok
+22:27 < matches> (0,0) - +(16292953875657448384,1) = -(16292953875657448384,2) seems wrong
+22:28 <@sulix> Pish! Nothing could be more beautiful.
+22:28 < matches> It's pretty hard to debug with such huge numbers :P
+22:31 <@sulix> Try this...
+22:31 * sulix pushes.
+22:32 < matches> What does that do...
+22:33 < matches> oh
+22:33 < matches> You negate the entire thing and add one
+22:33 < matches> Seems legit
+22:33 <@sulix> So "two's complement" negatives mean that -A == flip all bits of A and add 1.
+22:33 < matches> Yeah
+22:34 <@sulix> There seems to be a bug in the asm div_digits though.
+22:35 < matches> I'm taking that out until I know the main algorithm works :P
+22:35 < matches> Silly I spent so much time wondering why division was broken without checking subtraction
+22:36 < matches> After I spent all that time thinking I was so clever for doing division using bit shifts and subtractions
+22:37 <@sulix> It still takes forever.
+22:37 <@sulix> (Zooming in, that is)
+22:37 < matches> Nah there's still a bug
+22:37 < matches> You're running with an older version of realops test
+22:37 < matches> Hang on
+22:37 < matches> I will push things
+22:38 < matches> Trying to avoid a merge...
+22:38 <@sulix> And I will get a drink.
+22:44 < matches> So if you run enough tests you eventually get a bunch of SubBasic spam
+22:45 < matches> Which is actually occuring due to "<" operators
+22:45 <@sulix> Yeah: I'm going to add a bunch of hacks to "<" at some point.
+22:45 < matches> Which are in the Division loop ( >= is implemented in terms of <)
+22:45 < matches> Don't add the hacks until subtraction works!
+22:46 < matches> I don't want to optimise it yet
+22:46 < matches> Otherwise all the optimisations hide the bugs
+22:47 < matches> Time for a tester that just does subtractions I think
+22:48 <@sulix> It might be worth adding a bunch of SDL_assert_paranoid()'s everywhere that check that (a - b)+b == a and similar on every - call.
+22:49 < matches> Most of the tested numbers can be represented in a single digit which is causing problems
+22:50 < matches> With finding the bugs in the multi-digit algorithm
+22:52 < matches> For small enough multi digit Arbints testing against doubles might work?
+22:52 <@sulix> Maybe.
+22:53 <@sulix> You'd lose enough precision that it's not worth it for anything > 2 digits, I'd say.
+22:53 < matches> Yeah, 2 digits should be enough to make sure the algorithms actually work though
+22:54 < matches> 2 digits in one operand and 1 in the other (which will resize itself to have a leading zero if necessary)
+22:55 < matches> At some point I am going to have to use a library for Arbints and compare ours to it
+22:55 < matches> But I kind of want ours to work properly before bringing in an external one
+22:56 < matches> When I try floats I might just bring in the external library :P
+22:56 <@sulix> Two questions:
+22:57 <@sulix> 1. What is "borrow" supposed to be? Is it the "carry" or the "result has changed sign" or something else?
+22:57 <@sulix> 2. What do you think of replacing Sub() with Add() + Negate()?
+22:59 < matches> borrow's like carry (I'm using subtract with borrow in asm) it should get subtracted from the next digit, and if at the end it is still set then it means your result is less than zero
+22:59 < matches> and 2 sounds like an excellent idea
+23:00 <@sulix> Okay.
+23:00 <@sulix> 'cause there's a separate "carry" flag and "sign" flag, so I wasn't sure.
+23:01 < matches> subtract actually working would be slightly faster than add and then negate I think
+23:01 <@sulix> I'm not 100% sure if all the code is using m_sign as the sign or if some of it is trying to use 2's complement, which isn't really possible with arbints.
+23:03 < matches> When I was testing the subtraction code I was using int64_t instead of uint64_t and it seemed to work :S
+23:04 < matches> I should check whether sbb does unsigned or signed subtraction
+23:04 <@sulix> Both, I think.
+23:04 <@sulix> 2's complement makes them the same, which is why it's so nice.
+23:04 <@sulix> But it requires a fixed number of bits to work.
+23:09 < matches> Whoops now the bit shift tester runs forever as well
+23:13 < matches> Oh no it doesn't
+23:13 < matches> It just exceeds the limit on GrowDigits
+23:14 < matches> Phew
+23:14 < matches> Bit shifting works at least
+23:14 < matches> Or at least it is consistently broken
+23:14 < matches> (a >> X) << X == a
+23:14 < matches> But == could be broken
+23:14 < matches> NOTHING IS SAFE
+23:14 < matches> When you are writing your own number represntation :(
+23:15 <@sulix> Idea: 2's complement subtraction will make -ve numbers have an "infinite" number of 1s at the front, so would that be infinite looping, trying to continually add digits with 1s.
+23:15 < matches> Operator overloading is amazingly powerful and yet it seems like the best way to make seemingly sane code do batshit insane things
+23:15 <@sulix> I think the answer is "no: we're always trapping it and converting it" but am not sure.
+23:16 < matches> Our subtraction doesn't take forever
+23:16 < matches> The issue is when the result would be less than zero
+23:16 < matches> Hang on let me make another tester
+23:17 < matches> Well, I'll put it in the arbint tester instead of the real tester
+23:18 < matches> Since it's pretty clear the bugs are in arbint not rational<arbint> itself
+23:18 < matches> Although there might be bugs in rational<T> as well
+23:18 < matches> But we'll squish those when we get to them
+23:18 < matches> Also quad trees are they a thing yet?
+23:20 <@sulix> "The quadtrees aren't in the code, they were in your heart all along."
+23:21 < matches> Haha
+23:21 < matches> Tell that to Tim :P
+23:21 < matches> Ok (45,10) - (128,0) = -(83,18446744073709551605)
+23:21 < matches> But I'm pretty sure it should be -(83,9)
+23:21 < matches> + even
+23:22 < matches> (The least significant digit is first)
+23:23 < matches> Actually the plot thickens
+23:23 < matches> +45,10 - +128,0 = +18446744073709551533,9
+23:23 < matches> +45,10 - +128 = -83,18446744073709551605
+23:23 <@sulix> What is 0 + -1?
+23:24 < matches> +0 + -1 = -1
+23:24 <@sulix> I am pleased to hear that.
+23:25 < matches> +0 - +1 = -1
+23:25 <@sulix> -1 + 2?
+23:25 < matches> Now you're getting tricky...
+23:25 <@sulix> (As a maths major, I should know this)
+23:25 < matches> -1 - +2 = +1
+23:25 < matches> They're all single digit though
+23:26 <@sulix> Do you mean -1 + +2 = +1?
+23:26 <@sulix> Otherwise I'm slightly concerned.
+23:26 < matches> Uh yeah
+23:26 < matches> Sorry I have to change both the Arbint c(a + b) and the Debug
+23:26 < matches> Before copy pasting
+23:27 < matches> So I guess I should calculate if 45 + 10*2^64 - 128 == 18446744073709551533 + 9*2^64
+23:31 < matches> Expletive grenade
+23:31 < matches> I started Mathematica
+23:31 < matches> fglrx segfaulted
+23:31 < matches> startx
+23:32 < matches> -bash: /usr/bin/startx: No such file or directory
+23:32 < matches> Also now I am getting zenity int3 error messages all over the bottom line of my terminal
+23:33 < matches> Whyyy
+23:33 <@sulix> That's terrible.
+23:33 < matches> Why does this computer persecute me so
+23:34 < matches> I gave it a good life
+23:34 <@sulix> You should ask frames how he runs mathematica on the command line.
+23:34 < matches> I fed it lots of AC power
+23:34 < matches> I replaced that keyboard that I broke
+23:34 < matches> I only spilled coffee on it once
+23:34 < matches> I *tried* to use the drivers that weren't fglrx
+23:35 < matches> I give up, see you tomorrow. Try not to totally rewrite all the Arbint code :P
+23:35 < matches> I think the subtraction might actually work except for the resizing bit
+23:35 <@sulix> Nah, I'm calling it a night here too.
+23:36 <@sulix> I tried replacing the carry bit with the sign bit and all went to hell there, so I'm inclined to agree with you.
+23:37 < matches> Well using my calculator I get something with a 184 ish at the start and too many digits to display
+23:37 < matches> Hence the mathematica disaster
+23:40 < matches> Oh well, I got startx back by installing "xinit" so that's something
+23:41 < matches> I guess apt decided to remove it as part of apt-get autoremove in its infinite wisdom
+23:41 <@sulix> I have decided to never call apt-get autoremove.
+23:42 <@sulix> If at any point there are too many old packages for me to get things done, I'll just reinstall the OS entirely.
+--- Day changed Mon Jul 07 2014
+08:40 < matches> I try to avoid it, but sometimes apt won't let me do anything because it would break some dependency
+08:40 < matches> Although usually even after I run autoremove it complains
+08:41 < matches> Had to use aptitude to fix my "You can'd have kde-runtime!" issues
+08:45 < matches> Anyway wolfram alpha says that example +45,10 - +128 == +18446744073709551533,9
+08:45 < matches> is correct
+08:45 < matches> Checking the algorithm using 8 bits it should work too
+08:46 < matches> So it works as long as you supply the leading zeros...
+08:46 < matches> (On that particular case...)
+08:48 < matches> I hope it's not interpreting Arbint(128L) as Arbint(128u, ...)
+08:48 < matches> Nope sanity seems to prevail there
+08:50 < matches> Ah
+08:50 < matches> Ok
+08:50 < matches> First bug of the day: The subtracted argument needs to be resized
+08:50 < matches> As I am doing (45,10) - (128)
+08:59 < matches> :O
+08:59 < matches> I passed the realops test
+09:00 < matches> And it's also a lot faster now!
+09:00 < matches> Probably because the subtraction bug meant it was spending a long time in division to get the wrong result
+09:01 < matches> Yeah it should have been obvious division can't have been that slow for numbers starting at 64 bits since it does at most as many iterations as the number of bits
+09:01 < matches> Oh well
+09:02 < matches> Should probably not celebrate just yet, now the bezier looks really wierd again
+09:04 < matches> Ok
+09:04 < matches> Actually compiling with Real == Rational<Arbint> might be a better test
+09:04 < matches> But it still passes
+09:05 < matches> In particular it passes with Arbints where int64_t fails horribly
+09:05 < matches> So something is right
+09:05 < matches> Just not all of it...
+09:08 < matches> The GPU rendering seems to workish
+09:09 < matches> We really quickly end up with Arbints of size 30 digits or so :S
+09:09 < matches> Which is big enough to give an overflow in doubles I think
+09:10 < matches> Rational::ToDouble can probably be written as double(integer division) + Rational(remainder, quotient).ToDouble()
+09:10 < matches> (With some things to stop it recursing infinitely)
+09:20 < matches> Or even double(integer division) + double(remainder)/double(quotient)
+09:20 < matches> I don't think any recursion is needed
+09:22 < matches> Oh, there's a "pow" call that is probably broken
+09:24 <@sulix> Yeah, I feel the growing quickly is just a fact of life.
+09:25 <@sulix> Perhaps changing the zooming to avoid coprimes or something.
+09:27 <@sulix> I'm pretty certain that about 3 seconds of zooming is enough to make us need precision and range to match measuring the size of the visible universe in Planck lengths, too.
+09:28 <@sulix> "New biggest Arbint of size 173"
+09:28 <@sulix> and counting...
+09:34 < matches> haha
+09:34 < matches> There are more issues I spotted with add and subtract
+09:34 < matches> Basically you have to add the leading zeros - all of them
+09:35 < matches> My patch only simulates adding one leading zero
+09:35 < matches> Actually maybe I don't need to add them all, just enough until the borrow becomes zero
+09:36 < matches> But whatever
+09:36 < matches> If you're left with a borrow you can't assume that subtracting it from the next digit won't cause a borrow as well
+09:37 < matches> Realops is not a good enough tester
+09:42 <@sulix> Surely if there's borrow bit, subracting it from zero will always give another...?
+09:42 < matches> You only need as many as there are digits in your number
+09:42 < matches> At most
+09:42 < matches> If you still have a borrow at the end
+09:42 < matches> That means the result is negative
+09:43 <@sulix> Yeah, that's what I thought: you need to cap the number of digits you add.
+09:44 < matches> The problem was the algorithm before didn't finish all the borrows
+09:44 < matches> eg: 100 - 2 would have become "-8"
+09:44 < matches> Because 2 only has one digit
+09:44 <@sulix> My powers of mathematics tell me that that is not quite correct.
+09:45 < matches> What, that our algorithm was wrong?
+09:45 <@sulix> No, that 100-2 is not -8
+09:45 < matches> Yes
+09:45 < matches> Yes that's the problem :P
+09:46 < matches> So basically the two numbers need to be the same size but since we have a constant argument I'm sticking in a "borrow_digits" vector if there is a borrow
+09:46 < matches> Addition also needs it for carry
+09:46 < matches> Damn
+09:47 < matches> I'd hoped that might fix the beziers not looking like beziers on the CPU bug
+09:50 <@sulix> I've pushed code to clear the carry/borrow flag before adding/subtracting.
+09:50 <@sulix> I don't think any bug is triggered, but there was the potential for off-by-one errors.
+09:52 < matches> Argh no
+09:52 < matches> Merge
+09:53 < matches> Yeah I'm pushing a fix for bugs that I don't think we've seen (yet)
+09:54 <@sulix> Out of curiosity, I tried removing the Simplify() calls from Rational.
+09:54 <@sulix> Relatedly, I've coined the term "NaN soup"
+09:54 < matches> Oh, clearing the carry/borrow flag might actually fix a bug with the code I just committed
+09:54 < matches> No wait it won't
+09:55 < matches> Eh it's still kind of dangerous to assume it isn't set to start with
+09:55 <@sulix> I think the flag was probably already cleared by the code the compiler generated, but that might not be the case if it's optimized.
+09:55 < matches> One of my early attempts had inline adc instructions in a for loop
+09:56 < matches> Which failed miserably because the for loop was clearing the carry flag :P
+09:57 <@sulix> For some reason "*=" segfaults if optimization is enabled, but I don't know why.
+09:57 < matches> Yuk
+09:58 <@sulix> Somehow we end up with "mul" as a null reference.
+09:58 < matches> Rataional::*= or Arbint?
+09:58 <@sulix> Arbint
+09:58 <@sulix> (So, also rational)
+09:58 <@sulix> Valgrind isn't picking anything up.
+09:58 < matches> null references are the worst
+09:59 < matches> Since I'm pretty sure the point of a reference is that it is never null...
+09:59 < matches> I'm sure this doesn'
+09:59 < matches> t stop people from deliberately creating null references
+09:59 < matches> And also checking that they are not null
+10:02 <@sulix> Tried compiling with clang. Nope.
+10:02 <@sulix> Apparently not even #include <iostream> compiles with clang.
+10:02 < matches> It might be worth implementing a non assembly version of those functions
+10:03 <@sulix> Yeah, that's always a good idea.
+10:03 <@sulix> The assembly ones are more fun, though.
+10:16 < matches> Hmm I should probably head towards the meeting
+16:23 < matches> I have pushed a Gmpint wrapper thing
+16:23 < matches> It mimics Arbint as closely as possible.
+16:24 < matches> Well by that I mean I just wrapped all the calls to mpz_add() etc in operators
+16:24 < matches> It doesn't have all of Arbint's more esoteric functions
+16:24 < matches> If we need bit shifts I think I can add them
+16:27 < matches> So, writing stuff...
+16:28 < matches> Running arbint_vs_gmpint.test in valgrind takes a fair while
+16:28 < matches> We will have the definitive answer of just how terrible our multiplication is compared to the Professional (TM) implementation
+16:29 < matches> I do have some good news, I think our string conversion might be better
+16:29 < matches> Well if you ignore the division
+16:31 < matches> *= is about 11 times slower
+16:32 < matches> Most of that is in std::vector::resize()
+16:32 < matches> But even just mul_digits is greater than the entire Gmpint::operator*=
+16:32 < matches> The plot thickens as I try division
+16:32 < matches> Which is a good opportunity to get food because it will probably take an hour
+16:34 < matches> Note: Don't disable Debug messages if you want time to get food :(
+16:35 < matches> And division is just under 100* slower
+16:36 < matches> No
+16:36 < matches> 1000*
+16:37 < matches> So... if we change Rational<Arbint> to Rational<Gmpint>...
+16:41 < matches> We still get {nan,nan,nan,nan} eventually but it is generally less shoddy
+16:50 <@sulix> Cool: looking at this now.
+16:50 <@sulix> I'm digging through the gmp source code as well.
+16:51 <@sulix> They have a similar "divide by single int64_t" optimization.
+16:51 <@sulix> Also their code is 90% preprocessor macros.
+16:51 < matches> Welp
+16:51 < matches> At least we have a readable Arbint
+16:52 < matches> I don't know what use a readable but slow implementation is
+16:52 <@sulix> Ah: I see what they're doing: this is quite clever, particularly from a pure maths point of view.
+16:52 <@sulix> They've got a natural number implementation, and have then built their integer representation around that.
+16:53 <@sulix> The natural numbler implementation is just a huge set of directories with different assembly implementation.
+16:53 <@sulix> So there's an "x86_64" directory, and in that there's a bunch of assembly + a bunch of directories with optimized versions for different individual processor models.
+16:55 <@sulix> Also their assembly has lots of ASCII art comments.
+16:56 <@sulix> and macros.
+17:07 < matches> Yeah "just use GMP" is probably the answer
+17:08 < matches> Their Makefiles are pretty intimidating
+17:22 < matches> I like that they seem to store the sign as part of the size
+17:22 < matches> If something has a negative size it is negative and has |size| digits
+17:34 < matches> I guess I will try and write some sort of report about how we implemented Arbitrary Integers but they are terrible compared to existing implementations :P
+--- Day changed Thu Jul 24 2014
+14:44 < matches> So I was going to work on the project but existential dread
+14:45 < matches> About whether my major exists
+14:45 < matches> Do I exist?
+14:49 <@sulix> Are you thinking? Because cogito ergo sum.
+14:50 < matches> I'm not sure I was thinking when I picked this major...
+14:50 <@sulix> I did some project code yesterday and then a bug I thought I'd fixed reappeared so I got distracted failing to fix that.
+14:50 < matches> Haha
+14:53 < matches> Should I upset everyone and recommend freshers for wheel again...
+14:54 <@sulix> I'm all for it, but I think the consensus was that we need to make them actually do wheel-y projects first.
+14:55 < matches> That seems kind of hypocritical though
+14:55 < matches> Because nearly none of active wheel has actually done wheel-y projects
+14:55 < matches> Certainly not before getting on wheel
+14:56 <@sulix> My current random guess is that the problem is that people used to fix the desktops and stuff, and now everyone has their own laptops to break.
+14:56 < matches> But I'll be quiet or people might decide I need to be removed due to lack of doing useful things
+14:56 < matches> Yeah
+14:56 < matches> That too
+14:57 <@sulix> I'll definitely bring it up at the meeting.
+15:02 <@sulix> So which CoderDojo forms do I need to fill out?
+15:02 < matches> Ooh!
+15:02 < matches> http://coderdojowa.org.au/volunteer
+15:02 < matches> This one
+15:03 < matches> But now you've said that I'm already adding you to the mailing list...
+15:04 < matches> There's a thing on Saturday in 2.01 in CS at 12:00pm
+15:04 < matches> I hope people actually show up because we are pretty short on presenters
+15:04 <@sulix> Yeah, I've got a programming competition then. I'm trying to work out how much of the schedule for the competitions exists.
+15:06 <@sulix> Okay, apparently there are programming competitions every saturday in August, which will be fun.
+15:07 <@sulix> Although half of them are "details TBD," which sounds ominous.
+15:07 <@sulix> Also there is a round 2 and a round 4 but no round 3.
+15:11 <@sulix> Okay: it looks like the only weeks I don't have programming competitions on are the last 3 on the form.
+15:13 <@sulix> Also I suspect they're running out of names for the programming competitions, because this Saturday's is called the "South Pacific Winter Programming Carnival".
+15:21 < matches> Haha
+15:27 <@sulix> Form submitted. Sorry for the snarkiness.
+15:40 < matches> Brilliant
+15:40 < matches> You can do a C or C++ workshop or something :P
+15:40 < matches> Or just talk about Commander Keen that'll work
+15:40 < matches> Or "Why Javascript is awful and you should forget all the lessons"
+15:42 <@sulix> "Intro to DOS programming." :P
+18:38 < matches> I did a sort of half hearted attempt at writing more about Arbints
+18:39 < matches> Maybe I'll try put fonts in
+18:39 < matches> That seems vaguely like not what I am supposed to be doing right now :P
+18:43 < matches> There's that virtual FPU sitting there doing nothing
+18:43 < matches> That I promised to do things with in my lit review
+18:43 < matches> That Tim is marking
+18:43 < matches> When I haven't actually done anything with it and he knows it...
+18:44 < matches> I can't help but feel like we need a more impressive thing to zoom in on
+18:44 < matches> Or even a way to draw things once we have zoomed in
+18:46 < matches> Does "We implemented Arbitrary Precision Integers but GMP did it better" count as research?
+19:13 < matches> Do we have a memory leak?
+19:13 < matches> I've been running it for a while and things are slowing down
+19:25 <@sulix> matches: With GMP or just doubles?
+19:27 <@sulix> My quick check has us not leaking memory with doubles.
+19:27 <@sulix> Well, X leaks memory and the nVidia driver leaks memory, but we're fine.
+19:35 < matches> I was actually running with singles :S
+19:35 < matches> See push to documents repo
+19:35 < matches> There is a pdf
+19:35 < matches> I did a thing
+19:38 < matches> I'm basing the assumption that x86-64 is IEEE compliant on the fact that it passed the "paranoia" program
+19:39 <@sulix> Yeah, x86_64 is IEEE compliant.
+19:39 <@sulix> x86_32 is "mostly" IEEE compliant if I recall.
+19:41 < matches> Well a picture tells a thousand words
+19:41 < matches> So I think I wrote 8000 words today
+19:41 < matches> Progress!
+19:43 <@sulix> http://cgit.freedesktop.org/mesa/mesa/tree/src/mesa/drivers/dri/i965/brw_defines.h?id=9d6166880da83887e3246fb4498c3a07d979cc3b#n162
+19:43 <@sulix> I'll see if I can find where they actually set it to non IEEE.
+19:43 < matches> Oh I was going to say fglrx did different things to nVidea but as I don't have nVidea that's difficult to do
+19:45 <@sulix> Although there's this: http://lists.freedesktop.org/archives/mesa-dev/2013-July/041555.html
+19:45 <@sulix> Yeah, nVidia, Intel and fglrx all seem to do different things.
+19:45 <@sulix> fglrx does the strangest things.
+19:45 <@sulix> nVidia does the most consistant things.
+19:45 <@sulix> Intel sits nicely in the middle.
+19:46 < matches> If we can get four screenshots of the different things at the same view bounds that might be useful
+19:47 < matches> Also working out more about what the jagged edges implies about the precision/rounding might be helpful
+19:47 < matches> All I've got is "This is clearly not a circle"
+19:48 < matches> So it's still doing that with the quad trees enabled, so I assume the quad trees aren't amazingly quadifying everything yet :P
+19:48 <@sulix> The quadtrees are basically doing nothing but occasionally causing bugs.
+19:48 <@sulix> http://davidgow.net/stuff/ipdf-nvidia.png
+19:48 < matches> That is progress at least
+19:49 < matches> Thanks
+19:49 < matches> I will update the others to be the same view bounds
+19:49 < matches> I *think* we have code to set the view bounds at start?
+19:51 <@sulix> http://davidgow.net/stuff/ipdf-intel.png
+19:51 < matches> Haha
+19:51 < matches> Well it's really obvious that that's different
+19:52 < matches> Can you rerun it with -b 0.0869386 0.634194 2.63295e-07 2.63295e-07
+19:52 < matches> Obsessive compulsive...
+19:52 < matches> Must all be same view bounds...
+19:53 < matches> I'd run it on my other laptop with intel integrated graphics except the keyboard still doesn't work
+19:55 < matches> Actually don't bother
+19:55 <@sulix> http://davidgow.net/stuff/ipdf-nvidia1.png
+19:57 <@sulix> http://davidgow.net/stuff/ipdf-intel1.png
+19:59 < matches> oah wierd stuff is happening with the quad tree
+19:59 < matches> There is a big circle and a little circle
+19:59 < matches> Is that supposed to be here...
+20:00 < matches> The distance between them is not constant :S
+20:09 <@sulix> Yeah, that doesn't happen on intel and is the bug I've been hitting my head against.
+20:09 <@sulix> Pretty certain I'm trying to render one more object than there actually is somewhere, maybe corruping memory in the process.
+20:32 < matches> Ok so it turns out the CPU is actually about as terrible as the GPU at those view bounds when you replace the "double" with "float" in the Circle Renderer :S
+20:32 <@sulix> That's what I expected.
+20:32 <@sulix> It looks like the nVidia one, right?
+20:32 < matches> But it does slightly different wrong things!
+20:34 < matches> It looks similar-ish
+20:35 < matches> It is blocky as opposed to zig zaggy
+20:39 < matches> As in it doesn't look as whack as intel
+20:43 <@sulix> Hmm... I'm not sure what I'm doing wrong, but I can't see any artefacts at all with CPU rendering w/ those bounds.
+20:55 < matches> They are hard coded as doubles
+20:55 < matches> Not floats
+20:55 < matches> Or reals rather
+20:56 <@sulix> Ah.
+20:56 <@sulix> This explains much.
+21:08 < matches> I have pushed a thing
+21:09 < matches> It almost sounds like a real paper
+21:09 < matches> Until you realise all it is is "we drew some circles and they look different"
+21:09 < matches> Also your screenshots had some kind of crazy blue glowy border
+21:10 <@sulix> Yeah, that's the KDE window shadow.
+21:10 < matches> Fancy
+21:10 <@sulix> It used to make the nVidia driver corrupt screenshots, but it seems to work now.
+21:11 < matches> I'm pretty pleased with that 4 way comparison figure...
+21:12 < matches> "One of these things is not like the others..."
+21:12 < matches> *cough* intel
+21:12 <@sulix> The conclusion is brilliant.
+21:15 < matches> If we assume the nVidia and x86-64 figures are what things are supposed to look like
+21:15 < matches> fglrx tries really hard
+21:15 < matches> But doesn't quite make it
+21:16 < matches> (I'm pretty sure that's just a particularly good view for it)
+21:16 < matches> (If you move it around it goes insane)
+21:16 < matches> I can respect the intel shader
+21:16 < matches> It isn't afraid to blatantly disregard the rules
+21:17 < matches> intel driver rather
+21:17 < matches> Not sure why I put "shader" there
+21:17 < matches> This has not been as productive as I hoped
+21:18 < matches> Still
+21:18 < matches> We finally have something written that Tim can pass judgement on
+21:18 < matches> He's still in the country right?
+21:19 < matches> He might want to finish passing judgement on my literature review first :S
+21:21 <@sulix> I think he's still in the country, but don't hold me to that.
+21:22 < matches> Ok, so if you translate around with the CPU things don't go insane, but they do on the GPU. That might be caused by something else though.
+21:23 < matches> I'll be at University tomorrow
+21:24 <@sulix> I might head in, too, then.
+21:25 <@sulix> Do things still "go insane" on the GPU with CPU-side coordinate transforms.
+21:26 < matches> Yeah
+21:26 < matches> It looks like there is a tear
+21:27 < matches> So you get this rectangle pattern
+21:27 < matches> If you move it around on the CPU it maintains its shape
+21:28 <@sulix> I think that fglrx (or maybe just the AMD hardware) calculates the coordinates per-triangle rather than per-vertex or something.
+21:28 < matches> Under fglrx the bottom part of it sort of maintains its shape but there is a big diagonal line and the stuff above that changes
+21:28 <@sulix> That's pretty weird.
+21:29 < matches> Also the bottom part doesn't have concave bits but the top occasionally gets one
+21:29 < matches> concave/overhanging whatever
+21:29 <@sulix> The whole thing maintains its shape on nvidia (and even intel)
+21:29 < matches> Well, the bottom half (and also the CPU/nVidia entire thing) looks kind of like a stair case
+21:29 < matches> The top bit gets all these sticky out bits and overhangs
+21:30 < matches> Which brings us to our next paper
+21:30 < matches> The geology of fglrx
+21:30 <@sulix> Intel also does the "staircase" on the other side of the circle.
+21:30 < matches> On the other side...
+21:30 < matches> Hmm the plot thickens
+21:31 < matches> Oh well I need to sleep
+21:31 < matches> Why do I feel like I have actually lost sleep over the holidays...
+21:32 < matches> I am not ready for semester to start :(
+21:32 <@sulix> I know exactly what you mean.
+21:33 < matches> I seem to have been roped into unpaid work with physics
+21:34 <@sulix> Oh dear. More lab demonstrating or something more interesting?
+21:34 < matches> Hopefully if I visit ECM they won't make me do GENG5505 yet
+21:34 < matches> Fixing my honours experiment I think...
+21:35 <@sulix> Another pipe corroded through?
+21:35 < matches> Haha
+21:35 < matches> They were wondering where all the electronics went
+21:35 < matches> (I have most of it)
+21:35 < matches> (Also it's no longer functional)
+21:36 < matches> (I may have taken some of it apart...)
+21:36 < matches> (Although really the sensible option would have been to burn it with fire)
+21:37 < matches> Goodnight anyway
+21:37 <@sulix> I'm required to "correct" anything they want to change with this project after submitting it.
+21:37 <@sulix> On the morrow, then!
+--- Day changed Fri Jul 25 2014
+11:24 < matches> I'm at UCC
+11:39 <@sulix> Okay, I'll show up once I've sorted out this acedemic record stuff.
+12:05 < matches> I went to ECM but apparently just a few other people are having difficulties...
+18:24 < matches> So steam browser supports html5 canvas but not keyboard events
+18:24 < matches> This seems to happen with a lot of browsers
+18:25 < matches> We support html5 canvas (which is pretty much solely designed for web based games)
+18:25 < matches> But we don't support any way to actually pass input to the page that doesn't suck
+18:25 < matches> (I'm looking at you Safari)
+18:31 < matches> It sort of spoils the "HTML5 is AWESOME" message the HTML5 people are aiming for
+18:31 < matches> The best bit of html5 is <canvas> and that you no longer need to use html because you can just draw everything in the canvas...
+18:32 < matches> Which is scarily similar to using PostScript
+--- Day changed Mon Jul 28 2014
+10:05 < matches> In 2.07 now
+10:07 < matches> You removed SDL from contrib
+10:07 < matches> So now it won't compile on the lab machines
+10:07 * matches gets out the laptop then
+--- Day changed Tue Jul 29 2014
+09:59 < matches> I seem to have this bizarre illness
+10:00 < matches> Where half my head feels fine
+10:00 < matches> And the other half feels like I've been trying to read brainfuck
+10:00 < matches> I hope you don't catch it
+10:00 < matches> The side that is sick is the side that was closest to the group hug
+10:00 < matches> Coincidence!?
+10:00 < matches> I think not!
+10:08 < matches> You know how there's this theory about the two halves of the brain being semi independent and sort of subconsciously able to think by themselves
+10:08 < matches> I think the left side of my brain is dead
+10:08 < matches> It's not responding to pings
+10:09 < matches> I think the project working side might be the alive one though, so we shall see if I can actually do something useful
+--- Log closed Tue Jul 29 23:13:08 2014
+--- Log opened Wed Jul 30 12:03:38 2014
+12:03 -!- Irssi: #ipdf: Total of 2 nicks [1 ops, 0 halfops, 0 voices, 1 normal]
+12:03 -!- Irssi: Join to #ipdf was synced in 0 secs
+--- Day changed Sun Aug 03 2014
+12:43 < matches> So I found my moronic mistake with the virtual FPU and it seems to actually work
+12:44 < matches> I think it's even slower than using Rational<Arbint>
+12:44 < matches> Unless everything's slow because of the QT now
+12:45 < matches> There's an awful lot of "Rendering QT node" debug
+12:46 < matches> No its the VFPU that makes sense
+12:47 < matches> Since every floating point operation now requires writing 18 hex characters over a unix domain socket
+12:47 < matches> Hooray VHDL
+12:48 < matches> (I'm sure if you have $$$$ and like Enterprise(TM) software VHDL is great)
+12:48 < matches> I'll just do some miscellaneous things and hopefully some of them will be useful
+12:48 < matches> Bye
+14:14 < matches> So with the VFPU and doing everything on the GPU we have 2.2 FPS
+14:14 < matches> It seems to be able to cope with rectangles on the CPU
+14:15 < matches> The circle may present some difficulties
+14:16 < matches> It would be have been pretty cool to change the vfpu and see if anything makes it look like intel
+14:16 < matches> But ultimately useless I suppose
+14:37 < sulix> There might be some info in the hardware docs, though they're pretty incomprehensible: https://01.org/linuxgraphics/documentation/2013-intel-core-processor-family
+14:38 < sulix> AMD also have manuals: http://developer.amd.com/resources/documentation-articles/developer-guides-manuals/
+14:38 < sulix> nVidia are sworn to secrecy.
+--- Day changed Tue Aug 05 2014
+12:38 < matches> I'm looking at the atril source
+12:38 < matches> To see if I can compile it without the oppressive 400% max zoom
+12:39 < matches> It is rather intense
+12:39 < matches> I think the zooms are set depending on the language?
+12:41 < matches> There are po files which are definitely not position independent object files
+12:43 < matches> #define ZOOM_MAXIMAL(zoom_levels[n_zoom_levels - 1].level)
+12:43 < matches> The plot thickens!
+12:45 < matches> Heh this is actually sort of making sense
+12:45 < matches> They have a "cut-n-paste/zoom-control" directory
+12:48 < matches> I'm confused as to how the maximum zoom is 6400% and yet my version will only zoom to 400%
+12:48 < matches> But I guess I shall compile it from source and see what actually happens
+12:51 < matches> They also have a script to configure their configure script...
+12:51 < matches> Oh dear xml is involved
+12:53 < matches> There needs to be a way to save the status of configure so you don't have to rerun it from scratch every time you fix an error
+12:56 < matches> Our document viewer may only be able to render beziers and circles
+12:56 < matches> But at least it doesn't have any dependencies!
+12:56 < matches> Well many
+12:56 < matches> I suppose since SDL is in contrib we should put GMP in contrib too
+12:57 < matches> But yes, I don't care about caja plugins dammit I want to zoom on a pdf
+13:00 < matches> "Warning: Comparison between pointer and integer"
+13:00 < matches> Aaaah
+13:00 < matches> It compiles...
+13:01 < matches> But where did it put the binary...
+13:02 < matches> Oh great it expects things to be in /usr
+13:03 < matches> I guess I will run "install-sh" and hope I will still have a usable pdf viewer
+13:07 < matches> There's a LOT of G_ and g_ variables
+13:07 < matches> Actually functions
+13:07 < matches> I think g_ does not mean global in this context
+13:07 < matches> Maybe
+13:11 < matches> So it's not just a matter of ZOOM_MAXIMAL being redefined to ridiculously huge numbers having any effect
+13:11 < matches> I guess they use some other library that has zooming
+13:13 < matches> It somehow detects what the maximum zoom should be based on the document as well
+13:13 < matches> This is just over engineering!
+13:19 < matches> ev_view_can_zoom_in (EvView *view)
+13:19 < matches> return view->scale * ZOOM_IN_FACTOR <= ev_document_model_get_max_scale (view->model);
+13:19 < matches> Let
+13:19 * matches casually makes it return true
+13:19 < matches> Also wtf
+13:19 < matches> They have a "gboolean" type
+13:19 < matches> Is "bool" inferior?
+13:19 < matches> What more do you need than true and false
+13:20 < matches> Is bool used as a variable name for something
+13:20 < matches> sigh
+13:24 < matches> No ok it still won't let me zoom in more
+13:25 < matches> g_return_if_fail in the zoom functions
+13:25 < matches> They don't look important
+13:28 < matches> There are a surprising amount of places with a "if zoom or scale is bigger than the maximum, return"
+13:28 < matches> Like, are three checks really necessary
+13:29 < matches> I think you can set model->sizing_mode to "EV_SIZING_FREE" but I have no idea what that will do
+13:29 < matches> So I'll just continue commenting out anything that looks like it will return early from the zoom process...
+13:30 < sulix> Sounds like a plan!
+13:31 < matches> The use of g_ for function names makes me want to stab someone :P
+13:31 < matches> I assume it's related to gtk or maybe just gnome
+13:32 < matches> Also about half their doubles are "gdouble"
+13:32 < matches> And the other half are "double"
+13:32 < matches> :S
+13:32 < sulix> gtk had their own crazy, let's implement everything from scratch idea.
+13:32 < sulix> They have their own "classes" in C, IIRC.
+13:32 < matches> It's pretty object orientated yes
+13:34 < matches> Ok I seem to now be able to zoom in a *bit* more and then it just stops drawing things
+13:35 < matches> No wait it's just hopelessly slow
+13:37 < matches> It also zooms in on the wrong spot and then draws it and then moves the view back to the mouse and draws again
+13:38 < matches> But yes, it doesn't cope well with zooming at all
+13:38 < matches> I was kind of hoping it would work
+13:39 < matches> Maybe if I use a simpler document
+13:43 < matches> Congratulations anyway
+13:43 < matches> We can zoom further on a circle than atril can
+13:44 < matches> Unfortunately the reasons atril can't zoom are probably not related to precision
+13:44 < matches> Maybe I need to find some "if zoom > thing don't draw anything" and comment those out too
+13:44 < matches> Sigh
+14:07 < matches> It is resistant to my valgrind attempts
+14:07 < matches> It seems to have spawned 9 processes
+14:10 < matches> Oh "atril" is actually a series of hideous bash scripts that load libraries or something
+14:12 < matches> You know
+14:12 < matches> I'm sure if we tried
+14:12 < matches> We could make a less shitty pdf viewer out of our program
+14:29 < matches> Interesting
+14:30 < matches> "ev_document_render" got called 10.6 Billion times
+14:30 < matches> I don't think I changed the view that many times...
+14:32 < matches> Ok, so just working on our own viewer is probably better at this point than working out why atril has a heart attack if you zoom
+14:33 < matches> I'm going to pretend this wasn't a waste of time...
+14:41 < matches> "existing pdf viewers cap the view because otherwise they break due to bugs that aren't actually related to precision"
+15:43 < matches> So I suspect the GPU Bezier rendering is buggy
+15:44 < matches> Or maybe it's a quad tree thing
+15:45 < matches> Or both...
+15:46 < matches> I'm pretty sure the appearance of an individual bezier should not depend on what other beziers are in the document :P
+15:47 < matches> Yeah there's wierd quad tree shit going on
+15:48 < matches> I'm going to try and add some sort of glyph/font like thing
+15:49 < matches> It's either that or create hand drawn beziers in the current view
+15:50 < matches> But I feel it desperately needs an example of being able to actually zoom in and create something at an "arbitrary" level
+18:54 < matches> So we sort of have a very broken, very badly written, SVG parser
+18:55 < matches> A bunch of bugs showed up in the bezier rendering
+18:56 < matches> Although it might just be fglrx
+22:23 < sulix> The GL code is now consistantly broken, rather than sporadically broken.
+22:24 < sulix> Trying to render SVGs with it might count as modern art, though.
+22:39 < sulix> Man, the buggier the bézier code gets, the more beautiful its output.
+22:53 < sulix> Voilà: http://davidgow.net/stuff/ipdf-koch-svg.png
+23:11 < sulix> And on the CPU: http://davidgow.net/stuff/ipdf-koch-svg1.png
git.ucc.asn.au / ipdf / documents.git / blobdiff
UCC git Repository :: git.ucc.asn.au