Tom Cook wrote:
I don't know a lot about shaders; is floating point a "must" or would fixed point be possible? Fixed point would simplify the logic a good deal.
Tom, you and anybody else who wants to know what feature set is required for a programmable GPU need to read ARB_vertex_program specification <http://oss.sgi.com/projects/ogl-sample/registry/ARB/vertex_program.txt> ARB_fragment_program specification <http://oss.sgi.com/projects/ogl-sample/registry/ARB/fragment_program.txt> You can skip the early sections labelled "Issues" and "Additions to Chapter X of the OpenGL Specification" on a first reading, but you should read them afterwards because a lot of design choices are explained there. These date from 2003 so only represent the absolute minimum functionality for a 1st generation GPU. But that's enough to drive a lot of design choices: in MISC vs RISC, or fixed vs float, if it can't implement the ARB vertex and fragment shaders, it's a no go. (Note that these describe virtual machine instructions and that shaders are assembled at runtime on the target GPU, so it's OK for one ARB instruction to be translated into more than actual GPU operation.) After designing a GPU that can implement the ARB low level shaders, buy a copy of OpenGL Shading Language, 2nd edition Randi J Rost Addison-Wesley That's what modern GPUs are expected to implement. -- Hugh Fisher DCS, ANU _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
