On Sep 15, 2004, at 12:10 PM, chris clepper wrote:
On Sep 15, 2004, at 10:06 AM, r.leboite.pm@birdsinplane.com wrote:
Well the main extension i added is the possibility to render to a texture using the extension WGL_ARB_RENDER_TEXTURE which works pretty well now.
I also coded some tests about Cg Vertex Programs. Those programs work quite well but are not yet enough flexible to be commited.
Specifically, render-to-texture is part of the multiple windows and targets, and I think we will look at pBuffers to help achieve this. As for shaders, I would prefer not to use Cg for two reasons: one it's not part of ARB OpenGL, and not equally supported between platforms or vendors. Also, I think GLSL has potentially a superior architecture, although it might take ages for it to even be implemented fully on all three of GEM's target platforms. Both of these projects are still really in the planning stages, and various people are experimenting with potential solutions.
...I'm not familiar much with the ARB_Render_Texture api: a quick look at apple's OGL extensions guide doesn't list it, so that's a strike against implementing it in GEM (maybe it's covered under something else)...we'd already planned on doing other offscreen rendering targets via pbuffers...
...I'm not against have Cg capabilities, I just know from experience that it can be tricky to use cross-platform, and pretty much forget about using it with ATI cards (they have much different expectations)...that said, how are you implementing it? Are you intending to use the Cg runtime? I'd really be against that at this point...
...otoh, GLSL will definitely get implemented, but it's not available atm on OSX, so we're waiting...until then, what I've been working towards is just supporting the loading of ARB_vp and ARB_fp programs, which we can definitely do crossplatform atm...of course, this means that you have to write the shader in something other than the nicely intelligible GLSL or Cg :-)
You should become a developer since you are interested in working on advanced features, and also seem to be working on Windows. It would be good to have someone to help out with the render targets and shading, and you will get some help with figuring out GEM's internal architecture.
...I agree: at this point, you should make the code available somewhere online, or send it to the list (or just me: is anyone else working on this, too?) perhaps...then we can set up a branch to deal with these, get ya access, and then start digging!
james