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
git.ucc.asn.au / ipdf / documents.git / blobdiff
UCC git Repository :: git.ucc.asn.au