Can PhysX use GPU to simulate rigid bodies dynamics?

Gaming and Visualization Technologies APIs Physics Modeling (closed)
1

Hi.
Now, I’m developing a simulation program, and there are a lot of rigid bodies in the scene.
So I need a lot of time to simulate, then I try to accelerate the program to use GPU.

I found the method to simulate rigid bodies using CUDA on PhysX, however I couldn’t.

Is there a method to simulate rigid bodies using CUDA on PhysX?
And if there are no method, I need to write CUDA by myself?

2

Hi,
As far as I know, you just have to give your physX simulation a GPU dispatcher.
That’s done this way on our side:

PxCudaContextManager* cudaContaxtManager = initCudaContextManager(this);

if(cudaContaxtManager)
{
	if(!sceneDesc.gpuDispatcher)
	{
		sceneDesc.gpuDispatcher = cudaContaxtManager->getGpuDispatcher();
		TRACE_INFO(getPhysicsLog_PhysX(), "GPU acceleration activated on device: "<<cudaContaxtManager->getDeviceName()<<
						"\nDriver version: "<<cudaContaxtManager->getDriverVersion()<<
						"\nMemory: "<<cudaContaxtManager->getDeviceTotalMemBytes()<<
						"\nSM unit count: "<<cudaContaxtManager->getMultiprocessorCount()<<
						"\nSM clock frequency: "<<cudaContaxtManager->getClockRate());
	}
}
else
{
	finishCudaContextManager(this);
	TRACE_ERROR(getPhysicsLog_PhysX(), "Could not use GPU acceleration. Fall back on CPU.");
}

And then use the scene description as usual to initialize your physX simulation.

3

Thank you for your quick reply, grandYann:)

I tried your method, and I could give PhysX a GPU dispatcher.
However, my simulation program didn’t use GPU to simulate.

My simulation program uses only rigid bodies.
Can I use CUDA acceleration about rigid bodies?
Or is PhysX only support CUDA about cloth and particle?

4

Thank you for your quick reply, grandYann:)

I tried your method, and I could give PhysX a GPU dispatcher.
However, my simulation program didn’t use GPU to simulate.

My simulation program uses only rigid bodies.
Can I use CUDA acceleration about rigid bodies?
Or is PhysX only support CUDA about cloth and particle?

5

I’ve come to know since I answered that only particles and cloth are simulated on GPU, rigid bodies will always stay on CPU with this physX version ;)

6

Have you done any in-depth profiling to figure out where time is being spent or are you just assuming that its slow because you have a lot of rigid bodies and GPU simulation will be help. There is a lot of reason why the simulation could be slow ( again don’t know what metric is being used to measure this…and please don’t say frames per second ). How many rigid bodies is alot ? Are the rigid body using shared shapes, if not, can they be configured as such? Are you doing a lot of scene readback ? …and the list goes on.

7

Hello busta78,
sorry for the late reply.

I make a building on the scene.
There are about 8,000 rigid bodies, and each rigid bodies are connected by fixed joint.(The total of joint is 15,000)
And I want to enlarge the scale of simulation.

I don’t use sharing shapes, and that’s news to me.
I’ll try to check it.

Thank you.