art with code

2009-03-16

Bad juju Sunday

Had a crash in a demo. And found the culprit. It was from having a non-zero FBO bound when doing glXDestroyContext. Which was very WTF.

Allowing images and canvases with content from outside the current domain as textures is a bad idea, as you can read them with some GLSL trickery, even if you can't use getImageData/readPixels on the context. So that needs to be fixed. Which'll make the context quite a bit less useful, but it's either that or moving to a fixed-function pipeline.

One solution would be locking the context to use the GL fixed-function pipeline once you upload a texture outside the SOP. Or have a set of trusted shader programs that you could choose from. Or force a safe subset of the shading language. (Do I smell scope creep?)

And I finally managed to write a shader that takes a long time to run and hangs the GL driver for its duration. I'm just going to call that a driver problem. If there was some easy way to compute the maximum running time of a shader and reject ones that go over the threshold of acceptability, that could be used to reject potentially nasty shaders.

But I'm still going to call that a driver problem.
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Built art installations, web sites, graphics libraries, web browsers, mobile apps, desktop apps, media player themes, many nutty prototypes, much bad code, much bad art.

Have freelanced for Verizon, Google, Mozilla, Warner Bros, Sony Pictures, Yahoo!, Microsoft, Valve Software, TDK Electronics.

Ex-Chrome Developer Relations.