//! add Buoyancy force based on smoke density
KERNEL(bnd=1) void create_modifier_plane_horizontal(FlagGrid& flags, MACGrid& vel_modifier, Vec3 value) {
if (!flags.isFluid(i,j,k)) return;
if (flags.isFluid(i,j,k))
{
vel_modifier(i,j,k).x = value.x;
vel_modifier(i,j,k).y = value.y;
vel_modifier(i,j,k).z = value.z;
}
}
//! add Buoyancy force based on smoke density
KERNEL(bnd=1) void KnAddBuoyancy(FlagGrid& flags, Grid<Real>& density, MACGrid& vel, Vec3 strength) {
if (!flags.isFluid(i,j,k)) return;
if (flags.isFluid(i-1,j,k))
vel(i,j,k).x += (0.5 * strength.x) * (density(i,j,k)+density(i-1,j,k));
if (flags.isFluid(i,j-1,k))
vel(i,j,k).y += (0.5 * strength.y) * (density(i,j,k)+density(i,j-1,k));
if (vel.is3D() && flags.isFluid(i,j,k-1))
vel(i,j,k).z += (0.5 * strength.z) * (density(i,j,k)+density(i,j,k-1));
}
//! add Buoyancy force based on smoke density
KERNEL(bnd=1) void modify_velocity(FlagGrid& flags, MACGrid& vel, Vec3 value) {
if (!flags.isFluid(i,j,k)) return;
if (flags.isFluid(i,j,k))
{
vel(i,j,k).x = value.x;
vel(i,j,k).y = value.y;
vel(i,j,k).z = value.z;
}
}
//! 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 MakeRhs (FlagGrid& flags, Grid<Real>& rhs, MACGrid& vel,
Grid<Real>* perCellCorr)
{
if (!flags.isFluid(i,j,k)) {
rhs(i,j,k) = 0;
return;
}
// compute divergence
// assumes vel at obstacle interfaces is set to zero
/* Real set = 0;
if (!flags.isObstacle(i-1,j,k)) set += vel(i,j,k).x;
if (!flags.isObstacle(i+1,j,k)) set -= vel(i+1,j,k).x;
if (!flags.isObstacle(i,j-1,k)) set += vel(i,j,k).y;
if (!flags.isObstacle(i,j+1,k)) set -= vel(i,j+1,k).y;
if (!flags.isObstacle(i,j,k-1)) set += vel(i,j,k).z;
if (!flags.isObstacle(i,j,k+1)) set -= vel(i,j,k+1).z; */
Real set = vel(i,j,k).x - vel(i+1,j,k).x + vel(i,j,k).y - vel(i,j+1,k).y + vel(i,j,k).z - vel(i,j,k+1).z;
// per cell divergence correction
if(perCellCorr)
set += perCellCorr->get(i,j,k);
// obtain sum, cell count
sum += set;
cnt++;
rhs(i,j,k) = set;
}
void MacCormackCorrect(FlagGrid& flags, Grid<T>& dst, Grid<T>& old, Grid<T>& fwd, Grid<T>& bwd,
Real strength, bool isLevelSet, bool isMAC=false )
{
// note, replacement for isNotFluidMAC and isNotFluid
bool skip = false;
if (!flags.isFluid(idx)) skip = true;
if(!isMAC) {
if( (idx>=flags.getStrideX()) && (!flags.isFluid(idx-flags.getStrideX()) )) skip = true;
if( (idx>=flags.getStrideY()) && (!flags.isFluid(idx-flags.getStrideY()) )) skip = true;
if ( flags.is3D() ) {
if( (idx>=flags.getStrideZ()) &&(!flags.isFluid(idx-flags.getStrideZ()) )) skip = true;
} }
if ( skip ) {
dst[idx] = isLevelSet ? fwd[idx] : (T)0.0;
return;
}
// note, strenth of correction can be modified here
dst[idx] = fwd[idx] + strength * 0.5 * (old[idx] - bwd[idx]);
}
//! set no-stick wall boundary condition between ob/fl and ob/ob cells
KERNEL void KnSetWallBcs(FlagGrid& flags, MACGrid& vel, Vector3D<bool> lo, Vector3D<bool> up, bool admm) {
bool curFluid = flags.isFluid(i,j,k);
bool curObstacle = flags.isObstacle(i,j,k);
if (!curFluid && !curObstacle) return;
// MLE 2014-07-04
// if not admm, leave it as in orig
// if openBound, don't correct anything (solid is as empty)
// if admm, correct if vel is pointing outwards
// if "inner" obstacle vel
if(i>0 && curObstacle && !flags.isFluid(i-1,j,k)) vel(i,j,k).x = 0;
if(j>0 && curObstacle && !flags.isFluid(i,j-1,k)) vel(i,j,k).y = 0;
// check lo.x
if(!lo.x && i>0 && curFluid && flags.isObstacle(i-1,j,k) && ((admm&&vel(i,j,k).x<0)||!admm)) vel(i,j,k).x = 0;
// check up.x
if(!up.x && i>0 && curObstacle && flags.isFluid(i-1,j,k) && ((admm&&vel(i,j,k).x>0)||!admm)) vel(i,j,k).x = 0;
// check lo.y
if(!lo.y && j>0 && curFluid && flags.isObstacle(i,j-1,k) && ((admm&&vel(i,j,k).y<0)||!admm)) vel(i,j,k).y = 0;
// check up.y
if(!up.y && j>0 && curObstacle && flags.isFluid(i,j-1,k) && ((admm&&vel(i,j,k).y>0)||!admm)) vel(i,j,k).y = 0;
// check lo.z
if(!lo.z && k>0 && curFluid && flags.isObstacle(i,j,k-1) && ((admm&&vel(i,j,k).z<0)||!admm)) vel(i,j,k).z = 0;
// check up.z
if(!up.z && k>0 && curObstacle && flags.isFluid(i,j,k-1) && ((admm&&vel(i,j,k).z>0)||!admm)) vel(i,j,k).z = 0;
/* MLE consider later
if (curFluid) {
if ((i>0 && flags.isStick(i-1,j,k)) || (i<flags.getSizeX()-1 && flags.isStick(i+1,j,k)))
vel(i,j,k).y = vel(i,j,k).z = 0;
if ((j>0 && flags.isStick(i,j-1,k)) || (j<flags.getSizeY()-1 && flags.isStick(i,j+1,k)))
vel(i,j,k).x = vel(i,j,k).z = 0;
if (vel.is3D() && ((k>0 && flags.isStick(i,j,k-1)) || (k<flags.getSizeZ()-1 && flags.isStick(i,j,k+1))))
vel(i,j,k).x = vel(i,j,k).y = 0;
}
*/
}
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 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);
}
static inline bool isNotFluidMAC(FlagGrid& flags, int i, int j, int k)
{
if ( flags.isFluid(i,j,k) ) return false;
return true;
}