Comments on: Why not GPGPU?

By: Samu Mäntyniemi

Samu Mäntyniemi — Sat, 21 May 2011 20:41:11 +0000

Perhaps a slightly misplaced question, but I will ask it anyway:

Are we going to be able to run multiple scenery views on one computer with X-plane 10, in contrast to X-plane 9? I am thinking of a situation with 6-8 fast CPU cores and a powerful graphics card (perhaps with SLI or CrossFire) running 3 projectors using matrox triplehead2go or ATI eyefinity setup. Then having three scenery views angled to, say, -70,0,+70 degrees with 70 degrees FOV on each. The same computer could also show panels on separate monitors using the same or another graphics card.

Is this going to be possible, or would this still require 4 networked computers?

By: Ben Supnik

Ben Supnik — Sat, 14 May 2011 23:02:09 +0000

In reply to Lozz. Well, not 100% sure I agree re: OpenCL. If the GPU is not 100% maxed out or the machine has two GPUs, and the problem that needs accelerating can't easily be expressed in graphic terms, OpenCL could be useful. The structure of programs for OpenCL is different from both a traditional C program on the host CPU and pixel shaders. It just happens to be that in X-Plane graphics makes the CPU slow, so OpenGL is more useful.

By: Lozz

Lozz — Sat, 14 May 2011 22:55:49 +0000

OpenCL only looks useful for programs that don’t use the GPU at all. Using it on a game will take up precious rendering resources. If object rendering can be offloaded to the GPU and it’s faster then that will be good. Otherwise if objects could at least be threaded and really push all cores it should make a big difference. Objects and clouds seem to have the biggest performance impact, especially in a sim where they are so widespread. By the way I really like what you have planned with the cloud puffs vs distance from camera in XP10.