profiling

[joevenzon]

Hum, I know the scenegraph is a little heavier than it needs to be, but I'm surprised it's seeing so many samples in GetCollapsedDrawList. The only scenegraph nodes we should be collapsing per frame are the non-static objects. The static track objects only get collapsed once: at the end of GAME::LoadTrack. You're profiling the release optimized version, right? I wonder if the VC9 compiler is missing some optimization opportunities. You might want to try compiling with GCC and using the GNU profiler, then comparing the results. If you do "scons profiling=1" it'll compile with release optimizations, debugging symbols, and profiling all enabled (the framerate is lower with profiling enabled but it's still very playable). On my computer the frustum culling seems to take the longest. Moving to a hierarchical culling system would speed that up. I've also been thinking about how to make the scenegraph a little lighter weight.

About the texture stuff, I've always heard that OpenGL render state calls are pretty lightweight. Also, I assumed that the driver would take care of doing a NOOP instead of switching from a texture to an identical texture, but I could add that to VDrift pretty easily if it'd improve framerate (I'm not so sure it would). I've been meaning to get VDrift under perfHUD, but decided not to worry about it just yet since I'm planning on rewriting the rendering engine anyway.