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August 12, 2010
Music
freeform jam with chr


August 11, 2010
Home made iPhone tripod

I find my iPhone 3GS does a decent job as a video camera, so I made this:

4 Comments


August 4, 2010
Music
freeform jam with chr


July 31, 2010
Music
freeform jam with newt


July 30, 2010
Yes, I love technology

Here's a youtube collaboration I accidentally participated in:

I must say, these are exciting times... We have all kinds of crazy tools, it is so awesome.

1 Comment


July 28, 2010
Music
freeform jam with brennewtjoshnoj


July 25, 2010
Music
freeform jam with chr


July 23, 2010
Music
freeform jam with chrwiener


July 21, 2010
Music
newtbrenjosh - 1 -- [82:17]
newtbrenjosh - 2 -- [51:16]


July 19, 2010
Music
freeform jam with newt


July 13, 2010
Buggy fmod() with Visual C++ 2005/2008 targeting x64

I am posting this in case anybody debugging something needs to find it -- I did find mention of it on some Java related site, but nothing conclusive. This may affect VC2010, too, but I haven't tested it.

While VC 2005/2008 targeting x64 generates SSE code for floating point code, fmod() still uses the x87 FPU, and more importantly it assumes that the divide by 0 exception flag is clear going in (meaning if it is set prior to the call, the call will throw an exception or return #.IND regardless of the input). Apparently they assume that since the compiler won't possibly generate code that would cause the divide by 0 floating point exception flag to be set, then it would safe to assume that flag will always be clear. Or it could be a typo. If you use assembly code, or load a module compiled with another compiler that generates x87 code, this can be a huge problem.

Take this example (hi.cpp):

#include <stdio.h>
#include <math.h>

extern "C" void asmfunc();

int main() {
  asmfunc();
  printf("%f\n",fmod(1.0,2.0));
  return 0;
}

and hihi.asm (compile with nasm -f win64):

SECTION .text

global asmfunc
asmfunc:
  fld1
  fldz
  fdivp
  fstp st0
  ret

Compiling this (cl.exe hi.cpp hihi.obj) and running it does not print 1.0, as it should.

The solution we use is to call 'fclex' after any code that might use the FPU. Or not use fmod(). Or call fclex before fmod() every time. I should note that if you use ICC with VC200x, it doesn't have this problem (it presumably has a faster, correct fmod() implementation).

6 Comments


July 12, 2010
Music
brennewtjoshnoj - 1 -- [20:50]
brennewtjoshnoj - 2 -- [38:08]


July 6, 2010
Music
balls at 102


July 2, 2010
Music
chrwienerschwa - 1 -- [4:40]
chrwienerschwa - 2 -- [4:30]
chrwienerschwa - 3 -- [4:12]
chrwienerschwa - 4 -- [4:45]
chrwienerschwa - 5 -- [5:12]
chrwienerschwa - 6 -- [5:34]
chrwienerschwa - 7 -- [5:47]
chrwienerschwa - 8 -- [3:56]
chrwienerschwa - 9 -- [2:48]
chrwienerschwa - 10 -- [7:08]
chrwienerschwa - 11 -- [5:06]
chrwienerschwa - 12 -- [6:51]
chrwienerschwa - 13 -- [6:10]
chrwienerschwa - 14 -- [3:06]


June 30, 2010
Music
freeform jam with brennewtfritznoj


June 19, 2010
Music
freeform jam with 100623-newtbrennoj


June 14, 2010
Music
brennewt - 1 -- [79:16]
brennewt - 2 -- [23:24]


June 8, 2010
Music
freeform jam with newt


June 7, 2010
LICEcap!

We've just released a new piece of open source software for Windows, called LICEcap! It allows one to create animated screen captures. I know, there's a lot of software out there that does this already, but none of them are both free and meet my needs, so we made LICEcap.

LICEcap has a nice UI (in that you position/size the window where you want to capture, and can move it around while recording). We support writing to .GIF directly (big thanks/credit/blame to Schwa for getting the palette generation working as well as it does), as well as to a new format called .LCF.

LCF compresses by taking a series of frames, say, 20 frames, and then dividing each frame into slices, approx 128x16px each. Each slice is then compared to the same slice on the previous frame, and (if different) encoded directly after the previous frame. zlib is used to remove redundancy (often slices don't completely change from frame to frame, i.e. scrolls or small updates will compress very well). This is all done in 16bpp, and the end result is quite good compression, and lossless (well, 16bpp lossless) quality. REAPER supports playing back the .LCF files, too. The biggest down side is high memory use during compression/decompression (20 frames of 640x480x16bpp is about 12MB, and for smooth CPU distribution you end up using twice that).

I should mention that the primary reason for us making this tool was the desire to post animated gifs of new features in REAPER with the changelog. Hopefully we'll follow through on that.

On a related note, tomorrow (or soonish), I plan to post my latest additions on how to make OS X applications not perform terribly (new one: avoid avoid AVOID CGBitmapContextCreateImage() like the plague. HOLY CRAP it is bad to use). Apple: please, for the love of God, either make your documentation a Wiki, or hire someone who actually writes (multi-platform) applications with your APIs to write documentation.

9 Comments


June 4, 2010
Music
newtbrenbiderman - 1 -- [49:31]
newtbrenbiderman - 2 -- [33:59]


May 26, 2010
Music
freeform jam with brennewt


May 25, 2010
Music
freeform jam with chr


May 24, 2010
Music
freeform jam with chr


May 22, 2010
Music
freeform jam with chrtodd


May 19, 2010
this is the best movie i've ever seen



3 Comments


May 19, 2010
Music
freeform jam with brennewt


May 15, 2010
Music
brenchrnewtbiderman - 1 -- [87:25]
brenchrnewtbiderman - 2 -- [13:54]


May 12, 2010
Perhaps I am influenced by the design of rocket engine nozzles?



1 Comment


May 7, 2010
One pitch to go



10 Comments


May 5, 2010
The memory of Winter.



3 Comments


May 5, 2010
The rain is coming



1 Comment


May 5, 2010
Music
freeform jam with brennewtnoj


May 1, 2010
Music
wiener - 1 -- [5:52]
wiener - 2 -- [6:32]
wiener - 3 -- [8:42]
wiener - 4 -- [7:11]
wiener - 5 -- [10:03]


April 30, 2010
random iPhone notes fingerings from a plane

ca 1995, near Prescott: idle, on a rock, among the pines, at the foot of granite. the smell of trees and sap and pine needles, the warm sunshine and cool shade all comfort. having forgettable conversations with companions, names forgotten or not important, whose paths will diverge as inexplicably as they crossed. only good feelings remain.

Comment...


April 25, 2010
The funny/sad thing about releasing software is...

...if your test/beta/etc period is more than a few days, it doesn't matter how long it is, within 24 hours of releasing you'll almost always have brought to your attention a few very ugly bugs that need to be fixed. Sigh...

It makes me want to release things even more often.

7 Comments


April 14, 2010
Music
freeform jam with newtchrtodd


April 12, 2010
Music
freeform jam with chr


April 11, 2010
Dear Intel,

I've just read this article about your experimental 48-core CPU. Can I mention that our software, REAPER is highly multi-core optimized, and we'd love to see how it runs on / can be improved for 48 cores?

Sincerely,

Justin Frankel
Cockos Incorporated

P.S. We have REAPER running on Linux, too. Don't tell our users though, or they'll start whining (you know how Linux users can be).



10 Comments


April 10, 2010
Music
freeform jam with newttombren


March 31, 2010
Music
freeform jam with brennewtnoj


March 24, 2010
Stumptown

The best quote I've heard in a long time* (from a NYMag article):

    "Stumptown offers the best of the best. I'm not saying it to be arrogant, I'm saying it because it's a true fucking story."
I've found that agree with him.
* Allison actually read it to me many months ago, and it has stuck with us both ever since

3 Comments


March 20, 2010
Music
wiener - 1 -- [3:31]
wiener - 2 -- [3:32]
wiener - 3 -- [5:39]
wiener - 4 -- [4:01]
wiener - 5 -- [5:42]


March 12, 2010
software patent news

http://www.fsf.org/blogs/community/supreme-court-bilski

Here's hoping the supreme court does something good. Fingers are crossed.

1 Comment


March 9, 2010
Music
newt - 1 -- [13:04]
newt - 2 -- [13:26]
newt - 3 -- [4:54]


March 4, 2010
eeePC 901

I got a while back this ASUS eeePC 901, with a 1.6ghz Atom and 20GB of SSD. When I first got it I upgraded the RAM to 2GB, and installed Windows XP. It wasn't that great, so then I tried Win7 pro on it, which almost worked, but would just freeze for lengths of time for no apparent reason. The keyboard is tiny and has a very different arrangement from what I'm used to. It sat idle for a while, and since I have been developing on Linux (hello, SWELL/generic), I decided to install Ubuntu on it. The new verdict:

I love it. It's reasonably fast for compiling, installing new stuff is easy (apt-get ftw), Firefox w/ flash is fine, Xchat is decent enough, the stock mail client is very usable. The best part is that the battery life is fantastic, the screen is bright, there are very little moving parts, and it feels really solid. Yes, a bit like a toy, but I'm not worried about breaking it. Anyway, I'm fully on board with the netbook thing. Maybe next time I'd get one with a slightly larger keyboard, though...

Oh yeah and the other part of what I'm saying is: I'm definitely appreciating where Linux distributions for the desktop have gotten. Almost there... ;)

March 4, 2010
which reminds me: strict aliasing


I get that the "strict aliasing" optimization of recent C/C++ standards allow for great optimization. And I get that gcc has some anciently-designed optimizing, but at any rate, it annoys me that gcc will detect strict-aliasing violating code, and still go ahead and generate code that is obviously wrong -- i.e. when it knows that two pointers ARE in fact pointing to the same memory, it assumes that they can't possibly, and optimizes as if they don't. LLVM probably doesn't have the same problem, heh. Oh well I'll use -fno-strict-aliasing and meanwhile go through and use unions (and occasionally C++ templates) to make our stuff compatible with strict aliasing optimizations.

Of course, on performance sensitive code this is a huge time sink -- I ended up (on our anti-denormal code) looking at the output of many iterations of the same code on gcc i686, x86_64, vc6+icc10, vc2005+icc10, icc11 on osx, gcc ppc, etc, to try to find source code that worked properly and produced decent assembly code. The variety of code produced by each combination is staggering. Also, I found that often the code I thought would be fastest was not, when benchmarked. Oh well.



9 Comments


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