//----------------------------------------------------
// run the physics for all the particles
//----------------------------------------------------
private void simulateParticlesCPU(float deltaTime)
{
if (_useMultithreading)
{
if (_parallelForeach == null)
{
_parallelForeach = new ParallelForeach((a, b) => particleSimulationLogic(a, b, deltaTime));
}
_parallelForeach.Dispatch(NUM_PARTICLES);
_parallelForeach.Wait();
}
else
{
particleSimulationLogic(0, NUM_PARTICLES, deltaTime);
}
//----------------------------
// swap back and front buffer
//----------------------------
var temp = _backBuffer;
_backBuffer = _particles;
_particles = temp;
}
protected virtual void LateUpdate()
{
if (_useMultithreading)
{
using (new ProfilerSample("Wait For Simulation Jobs")) {
_integrationForeach.Wait();
_resolveCollisionsForeach.Wait();
}
}
MaterialPropertyBlock block = new MaterialPropertyBlock();
Matrix4x4 matrix;
using (new ProfilerSample("Draw Particles")) {
switch (_renderMethod)
{
case DisplayMethod.DrawMesh:
for (int i = 0; i < _aliveParticles; i++)
{
matrix = Matrix4x4.TRS(_particlesFront[i].position, Quaternion.identity, Vector3.one * PARTICLE_DIAMETER);
Graphics.DrawMesh(_particleMesh, matrix, _displayMaterial, 0);
}
break;
case DisplayMethod.DrawMeshInstanced:
int remaining = _aliveParticles;
int index = 0;
int colorIndex = 0;
matrix = Matrix4x4.identity;
matrix[0, 0] = PARTICLE_DIAMETER;
matrix[1, 1] = PARTICLE_DIAMETER;
matrix[2, 2] = PARTICLE_DIAMETER;
while (remaining > 0)
{
int toDraw = Mathf.Min(1023, remaining);
using (new ProfilerSample("Copy Particle Positions")) {
for (int i = 0; i < toDraw; i++)
{
matrix[0, 3] = _particlesFront[index].position.x;
matrix[1, 3] = _particlesFront[index].position.y;
matrix[2, 3] = _particlesFront[index].position.z;
_instanceMatrices[i] = matrix;
_instanceColors[i] = _speciesData[_particlesFront[index].species].color;
index++;
}
remaining -= toDraw;
}
if (_showInstanceChunks)
{
block.SetColor("_Color", _randomColors[colorIndex++]);
}
else
{
block.SetVectorArray("_Color", _instanceColors);
}
using (new ProfilerSample("Draw Mesh Instanced")) {
Graphics.DrawMeshInstanced(_particleMesh, 0, _displayMaterial, _instanceMatrices, toDraw, block);
}
}
break;
}
}
}