private void UpdateMesh()
{
// Return early if mesh is null.
if (mDescriptor.EmittMesh == null)
{
return;
}
// Return early if mesh is loaded.
if (sEmittMeshInfoDictionary.ContainsKey(mDescriptor.EmittMesh))
{
return;
}
Vector3[] vertices = mDescriptor.EmittMesh.vertices;
int[] indices = mDescriptor.EmittMesh.triangles;
// Create new emitt mesh info from mesh.
EmittMeshInfo emittMeshInfo = new EmittMeshInfo();
emittMeshInfo.mVertexCount = vertices.GetLength(0);
emittMeshInfo.mVertexBuffer = new ComputeBuffer(vertices.GetLength(0), sizeof(float) * 3);
emittMeshInfo.mVertexBuffer.SetData(vertices);
emittMeshInfo.mIndexCount = indices.GetLength(0);
emittMeshInfo.mIndexBuffer = new ComputeBuffer(indices.GetLength(0), sizeof(int));
emittMeshInfo.mIndexBuffer.SetData(indices);
// Add to dictionary.
sEmittMeshInfoDictionary[mDescriptor.EmittMesh] = emittMeshInfo;
}
// EMITT UPDATE.
private void EmittUpdate()
{
// Update timer.
mEmittTimer += Time.deltaTime;
int emittCount = (int)(mDescriptor.EmittFrequency * mEmittTimer);
if (emittCount == 0)
{
return;
}
mEmittTimer -= emittCount * 1.0f / mDescriptor.EmittFrequency;
Vector3 emitterVelocity = transform.position - mLastPosition;
int particlesToEmitt = emittCount;
int batchCount = (int)Mathf.Ceil(emittCount / 64.0f);
for (int batchID = 0; batchID < batchCount; ++batchID)
{
int emittCountThisBatch = particlesToEmitt > 64 ? 64 : particlesToEmitt;
//Debug.Log(emittCountThisBatch);
particlesToEmitt -= 64;
sComputeShader.SetInt("gEmittCountThisBatch", emittCountThisBatch);
// BIND PARTICLE BUFFERS.
sComputeShader.SetBuffer(sKernelEmitt, "gPositionBuffer", mPositionBuffer.GetOutputBuffer());
sComputeShader.SetBuffer(sKernelEmitt, "gVelocityBuffer", mVelocityBuffer.GetOutputBuffer());
sComputeShader.SetBuffer(sKernelEmitt, "gLifetimeBuffer", mLifetimeBuffer.GetOutputBuffer());
// Inherit velocity from emitter if true.
Vector3 velocity = (emitterVelocity / Time.deltaTime) * (mDescriptor.InheritVelocity ? 1 : 0) + mDescriptor.InitialVelocity;
// EMITT INFO.
sComputeShader.SetInt("gEmittStartIndex", mEmittIndex);
sComputeShader.SetInt("gEmittMaxCount", mMaxParticleCount);
sComputeShader.SetFloats("gPosition", new float[] { transform.position.x, transform.position.y, transform.position.z });
sComputeShader.SetFloats("gVelocity", new float[] { velocity.x, velocity.y, velocity.z });
sComputeShader.SetFloats("gLifetime", new float[] { mDescriptor.Lifetime });
// EMITT MESH.
if (mDescriptor.EmittMesh == null)
{
// Set count to 0.
sComputeShader.SetInt("gEmittMeshVertexCount", 0);
sComputeShader.SetInt("gEmittMeshIndexCount", 0);
sComputeShader.SetInt("gEmittMeshRandomIndex", 0);
}
else
{
Debug.Assert(sEmittMeshInfoDictionary.ContainsKey(mDescriptor.EmittMesh));
EmittMeshInfo emittMeshInfo = sEmittMeshInfoDictionary[mDescriptor.EmittMesh];
// Set index and vertex buffer.
sComputeShader.SetBuffer(sKernelEmitt, "gEmittMeshVertexBuffer", emittMeshInfo.mVertexBuffer);
sComputeShader.SetBuffer(sKernelEmitt, "gEmittMeshIndexBuffer", emittMeshInfo.mIndexBuffer);
sComputeShader.SetInt("gEmittMeshVertexCount", emittMeshInfo.mVertexCount);
sComputeShader.SetInt("gEmittMeshIndexCount", emittMeshInfo.mIndexCount);
int[] randomIndexArray = new int[64];
for (int j = 0; j < randomIndexArray.GetLength(0); ++j)
{
randomIndexArray[j] = Random.Range(0, emittMeshInfo.mIndexCount - 1);
}
sRandomIndexBuffer.SetData(randomIndexArray);
sComputeShader.SetBuffer(sKernelEmitt, "gEmittMeshRandomIndexBuffer", sRandomIndexBuffer);
sComputeShader.SetFloats("gEmittMeshScale", new float[] { transform.localScale.x, transform.localScale.y, transform.localScale.z });
}
// DISPATCH.
sComputeShader.Dispatch(sKernelEmitt, 1, 1, 1);
// Increment emitt index.
mEmittIndex = (mEmittIndex + emittCountThisBatch) % mMaxParticleCount;
}
}