//! add Forces between fl/fl and fl/em cells
KERNEL(bnd=1) void KnAddForce(FlagGrid& flags, MACGrid& vel, Vec3 force) {
bool curFluid = flags.isFluid(i,j,k);
bool curEmpty = flags.isEmpty(i,j,k);
if (!curFluid && !curEmpty) return;
if (flags.isFluid(i-1,j,k) || (curFluid && flags.isEmpty(i-1,j,k)))
vel(i,j,k).x += force.x;
if (flags.isFluid(i,j-1,k) || (curFluid && flags.isEmpty(i,j-1,k)))
vel(i,j,k).y += force.y;
if (vel.is3D() && (flags.isFluid(i,j,k-1) || (curFluid && flags.isEmpty(i,j,k-1))))
vel(i,j,k).z += force.z;
}
void ApplyGhostFluid (FlagGrid& flags, Grid<Real>& phi, Grid<Real>& A0, Real accuracy)
{
if (!flags.isFluid(i,j,k))
return;
const Real curPhi = phi(i,j,k);
if (flags.isEmpty(i-1,j,k)) A0(i,j,k) += getGhostMatrixAddition( phi(i-1,j,k), curPhi, accuracy);
if (flags.isEmpty(i+1,j,k)) A0(i,j,k) += getGhostMatrixAddition( curPhi, phi(i+1,j,k), accuracy);
if (flags.isEmpty(i,j-1,k)) A0(i,j,k) += getGhostMatrixAddition( phi(i,j-1,k), curPhi, accuracy);
if (flags.isEmpty(i,j+1,k)) A0(i,j,k) += getGhostMatrixAddition( curPhi, phi(i,j+1,k), accuracy);
if (flags.is3D() && flags.isEmpty(i,j,k-1)) A0(i,j,k) += getGhostMatrixAddition( phi(i,j,k-1), curPhi, accuracy);
if (flags.is3D() && flags.isEmpty(i,j,k+1)) A0(i,j,k) += getGhostMatrixAddition( curPhi, phi(i,j,k+1), accuracy);
}
void CorrectVelocity(FlagGrid& flags, MACGrid& vel, Grid<Real>& pressure)
{
// correct all faces between fluid-fluid and fluid-empty cells
// skip everything with obstacles...
if (flags.isObstacle(i,j,k))
return;
// skip faces between two empty cells
const bool curEmpty = flags.isEmpty(i,j,k);
const Real p = pressure(i,j,k);
if (!curEmpty || !flags.isEmpty(i-1,j,k)) vel(i,j,k).x -= (p - pressure(i-1,j,k));
if (!curEmpty || !flags.isEmpty(i,j-1,k)) vel(i,j,k).y -= (p - pressure(i,j-1,k));
if (!curEmpty || !flags.isEmpty(i,j,k-1)) vel(i,j,k).z -= (p - pressure(i,j,k-1));
}
void CorrectVelGhostFluid (FlagGrid& flags, MACGrid& vel, Grid<Real>& pressure) //, Grid<Real>& phi)
{
bool curFluid = flags.isFluid(i,j,k);
if (!curFluid && !flags.isEmpty(i,j,k))
return;
const Real curPress = pressure(i,j,k);
//const Real curPhi = phi(i,j,k);
// TODO - include ghost fluid factor NT_DEBUG
// in contrast to old implementation:
// make sure to add gradient for all fluid-empty or fluid-fluid combinations
// of neighbors...
if (!flags.isObstacle(i-1,j,k) && (curFluid || flags.isFluid(i-1,j,k)))
vel(i,j,k).x -= curPress - pressure(i-1,j,k);
if (!flags.isObstacle(i,j-1,k) && (curFluid || flags.isFluid(i,j-1,k)))
vel(i,j,k).y -= curPress - pressure(i,j-1,k);
if (flags.is3D() && (!flags.isObstacle(i,j,k-1) && (curFluid || flags.isFluid(i,j,k-1))))
vel(i,j,k).z -= curPress - pressure(i,j,k-1);
}