//argument buffer for GPU instance drawing
//private ComputeBuffer m_argsBuffer;
public FluidBoundary(ParticleSource source, float radius, float density, Matrix4x4 RTS)
{
NumParticles = source.NumParticles;
ParticleRadius = radius;
DensityCoeff = density;
CreateParticles(source, RTS);
CreateBoundryPsi();
}
private void CreateParticles(ParticleSource source, Matrix4x4 RTS)
{
Vector4[] positions = new Vector4[NumParticles];
float inf = float.PositiveInfinity;
Vector3 min = new Vector3(inf, inf, inf);
Vector3 max = new Vector3(-inf, -inf, -inf);
for (int i = 0; i < NumParticles; i++)
{
Vector4 pos = RTS * source.Positions[i];
positions[i] = pos;
if (pos.x < min.x)
{
min.x = pos.x;
}
if (pos.y < min.y)
{
min.y = pos.y;
}
if (pos.z < min.z)
{
min.z = pos.z;
}
if (pos.x > max.x)
{
max.x = pos.x;
}
if (pos.y > max.y)
{
max.y = pos.y;
}
if (pos.z > max.z)
{
max.z = pos.z;
}
}
min.x -= ParticleRadius;
min.y -= ParticleRadius;
min.z -= ParticleRadius;
max.x += ParticleRadius;
max.y += ParticleRadius;
max.z += ParticleRadius;
Bounds = new Bounds();
Bounds.SetMinMax(min, max);
PositionsBuffer = new ComputeBuffer(NumParticles, 4 * sizeof(float));
PositionsBuffer.SetData(positions);
}
public FluidBody(ParticleSource source, float radius, float density, Matrix4x4 RTS, Vector3 initialVel)
{
NumParticles = source.NumParticles;
Density = density;
ViscosityCoeff = 0.002f;
DampingCoeff = 0.0f;
ParticleRadius = radius;
ParticleVolume = (4.0f / 3.0f) * Mathf.PI * Mathf.Pow(radius, 3);
ParticleMass = ParticleVolume * Density;
DensitiesBuffer = new ComputeBuffer(NumParticles, sizeof(float));
PressuresBuffer = new ComputeBuffer(NumParticles, sizeof(float));
CreateParticles(source, RTS, initialVel);
}
private void CreateParticles(ParticleSource source, Matrix4x4 RTS, Vector3 initialVel)
{
Vector4[] positions = new Vector4[NumParticles];
Vector4[] predicted = new Vector4[NumParticles];
Vector4[] velocities = new Vector4[NumParticles];
float inf = float.PositiveInfinity;
Vector3 min = new Vector3(inf, inf, inf);
Vector3 max = new Vector3(-inf, -inf, -inf);
for (int i = 0; i < NumParticles; i++)
{
Vector4 pos = RTS * source.Positions[i];
positions[i] = pos;
predicted[i] = pos;
//modified: add initial velocity to the particles
//velocities[i] = new Vector3(5.0f, 0.0f, 0.0f);
velocities[i] = initialVel;
if (pos.x < min.x)
{
min.x = pos.x;
}
if (pos.y < min.y)
{
min.y = pos.y;
}
if (pos.z < min.z)
{
min.z = pos.z;
}
if (pos.x > max.x)
{
max.x = pos.x;
}
if (pos.y > max.y)
{
max.y = pos.y;
}
if (pos.z > max.z)
{
max.z = pos.z;
}
}
min.x -= ParticleRadius;
min.y -= ParticleRadius;
min.z -= ParticleRadius;
max.x += ParticleRadius;
max.y += ParticleRadius;
max.z += ParticleRadius;
Bounds = new Bounds();
Bounds.SetMinMax(min, max);
PositionsBuffer = new ComputeBuffer(NumParticles, 4 * sizeof(float));
PositionsBuffer.SetData(positions);
//Predicted and velocities use a double buffer as solver step
//needs to read from many locations of buffer and write the result
//in same pass. Could be removed if needed as long as buffer writes
//are atomic. Not sure if they are.
PredictedBuffer = new ComputeBuffer[2];
PredictedBuffer[0] = new ComputeBuffer(NumParticles, 4 * sizeof(float));
PredictedBuffer[0].SetData(predicted);
PredictedBuffer[1] = new ComputeBuffer(NumParticles, 4 * sizeof(float));
PredictedBuffer[1].SetData(predicted);
VelocitiesBuffer = new ComputeBuffer[2];
VelocitiesBuffer[0] = new ComputeBuffer(NumParticles, 4 * sizeof(float));
VelocitiesBuffer[0].SetData(velocities);
VelocitiesBuffer[1] = new ComputeBuffer(NumParticles, 4 * sizeof(float));
VelocitiesBuffer[1].SetData(velocities);
}