Are you sure the issue is with bullet and not your graphics engine? You'll need to turn on a profiler to see what's taking up your cycles.
Even with 600 simulations a second at 10 iterations for a hundred objects, any cpu better than an old E8400 should be able to do above 11fps without really worrying about optimizations (assuming release version with box on box with practically no collisions as seen in your video). It's doubtful that your graphics runs higher than 60fps though, so you would be simulating 1/10th of a physics frame per graphics frame, resulting in every second of graphics simulating 1/10th of a second.
A bigger question is what you are trying to accomplish with your program. If you are trying to simulate at 600fps, the code should actually be closer to
Code: Select all
dynamicsWorld->stepSimulation(graphicDelta,20, 1/600.f);
where the graphicDelta represents the time spent between graphics frames. If you are trying to simulate something at regular speeds with a slow graphics program, you could try
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dynamicsWorld->stepSimulation(graphicDelta,10);
You should read
http://bulletphysics.org/mediawiki-1.5. ... _the_World to check what type of settings are good for the program you are trying to make.