X-Git-Url: https://git.ucc.asn.au/?p=ipdf%2Fdocuments.git;a=blobdiff_plain;f=irc%2F%23ipdf.log;h=7b7170385bb58199f13bd0f1b913f76ebc2e8040;hp=89f71a4840cc7f60f482ec3d8d161e5f46e5070c;hb=dd88f40323a47bdcf44bffcd988847affd4ebd15;hpb=6f5f55579b969668419ea925e07f6c86442ef582 diff --git a/irc/#ipdf.log b/irc/#ipdf.log index 89f71a4..7b71703 100644 --- a/irc/#ipdf.log +++ b/irc/#ipdf.log @@ -793,3 +793,142 @@ 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 +18:04 -!- Pommers [bobgeorge33@motsugo.ucc.gu.uwa.edu.au] has joined #ipdf +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! +18:05 -!- Pommers [bobgeorge33@motsugo.ucc.gu.uwa.edu.au] has left #ipdf [] +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