void LevelSetOperator::IntegrateEuler(float dt)
{
// Create grid used to store next time step
LevelSetGrid grid = GetGrid();
// Iterate over grid and compute the grid values for the next timestep
LevelSetGrid::Iterator iter = GetGrid().BeginNarrowBand();
LevelSetGrid::Iterator iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k, GetGrid().GetValue(i,j,k) + ddt*dt);
iter++;
}
// Update the grid with the next time step
GetGrid() = grid;
}
void LevelSetOperator::GridLerp(const LevelSetGrid & grid1,const LevelSetGrid & grid2,float factor,LevelSetGrid & gridOut)
{
// Iterate over grid and compute the grid values for the next timestep
gridOut = grid1;
LevelSetGrid::Iterator iter = grid1.BeginNarrowBand();
LevelSetGrid::Iterator iend = grid1.EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute the next time step and store it in the grid
gridOut.SetValue(i,j,k, grid1.GetValue(i,j,k)*factor + grid2.GetValue(i,j,k)*(1.0f-factor));
iter++;
}
}
void LevelSetOperator::EulerStep(LevelSetGrid & gridOut,float dt)
{
// Iterate over grid and compute the grid values for the next timestep
gridOut = GetGrid();
LevelSetGrid::Iterator iter = GetGrid().BeginNarrowBand();
LevelSetGrid::Iterator iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);
// Compute the next time step and store it in the grid
gridOut.SetValue(i,j,k, GetGrid().GetValue(i,j,k) + ddt*dt);
iter++;
}
}
void LevelSetOperator::IntegrateRungeKutta(float dt)
{
/*
TVD RK
*/
/*
//Spara värdet för n samt beräkna n+1
LevelSetGrid grid = GetGrid();
LevelSetGrid gridOldPhi(grid.GetDimX(),grid.GetDimY(),grid.GetDimZ()) ;
LevelSetGrid::Iterator iter = GetGrid().BeginNarrowBand();
LevelSetGrid::Iterator iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i n
gridOldPhi.SetValue(i,j,k,GetGrid().GetValue(i,j,k));
float phi_new = GetGrid().GetValue(i,j,k) + ddt*dt;
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k,phi_new);
iter++;
}
GetGrid() = grid;
//Beräkna nytt n+1 via n och n+2
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k); //Beräkna derivatan i n+1
float old_phi = gridOldPhi.GetValue(i,j,k);
float phi_new = 0.5*(old_phi + (GetGrid().GetValue(i,j,k) + ddt*dt));//0.5(n + (n+2)) = n+1
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k,phi_new);
iter++;
}
GetGrid() = grid;*/
/*
//K1
LevelSetGrid grid = GetGrid();
LevelSetGrid y(grid.GetDimX(),grid.GetDimY(),grid.GetDimZ()) ;
LevelSetGrid k1(grid.GetDimX(),grid.GetDimY(),grid.GetDimZ()) ;
LevelSetGrid::Iterator iter = GetGrid().BeginNarrowBand();
LevelSetGrid::Iterator iend = GetGrid().EndNarrowBand();
while (iter != iend)
{
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i k1
y.SetValue(i,j,k,GetGrid().GetValue(i,j,k));
k1.SetValue(i,j,k,ddt*dt);
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k, y.GetValue(i,j,k) + (1.0/2.0)*k1.GetValue(i,j,k));
iter++;
}
GetGrid() = grid;
//K2
LevelSetGrid k2(grid.GetDimX(),grid.GetDimY(),grid.GetDimZ()) ;
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend)
{
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i k2
k2.SetValue(i,j,k,ddt*dt);
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k, y.GetValue(i,j,k) + (1.0/2.0)*k2.GetValue(i,j,k));
iter++;
}
GetGrid() = grid;
//K3
LevelSetGrid k3(grid.GetDimX(),grid.GetDimY(),grid.GetDimZ()) ;
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend)
{
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i k3
k3.SetValue(i,j,k,ddt*dt);
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k, y.GetValue(i,j,k) + k3.GetValue(i,j,k));
iter++;
}
GetGrid() = grid;
//K4
LevelSetGrid k4(grid.GetDimX(),grid.GetDimY(),grid.GetDimZ()) ;
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend)
{
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i k3
k4.SetValue(i,j,k,ddt*dt);
iter++;
}
GetGrid() = grid;
//Beräkna nytt n+1 via n och n+2
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
float yn = y.GetValue(i,j,k);
float k1n = k1.GetValue(i,j,k);
float k2n = k2.GetValue(i,j,k);
float k3n = k3.GetValue(i,j,k);
float k4n = k4.GetValue(i,j,k);
float new_y = yn + (1.0/6.0)*(k1n+k4n) + (1.0/3.0)*(k2n + k3n);
grid.SetValue(i,j,k,new_y);
iter++;
}
GetGrid() = grid;*/
LevelSetGrid grid = GetGrid();
LevelSetGrid n(grid.GetDimX(),grid.GetDimY(),grid.GetDimZ()) ;
LevelSetGrid::Iterator iter = GetGrid().BeginNarrowBand();
LevelSetGrid::Iterator iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i n
n.SetValue(i,j,k,GetGrid().GetValue(i,j,k));
float n1 = GetGrid().GetValue(i,j,k) + ddt*dt;
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k,n1);
iter++;
}
GetGrid() = grid;
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i n
float n2 = GetGrid().GetValue(i,j,k) + ddt*dt;
float n0 = n.GetValue(i,j,k);
float n1 = (n0+n2)/2.0;
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k,n1);
iter++;
}
GetGrid() = grid;
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i n
float n2 = GetGrid().GetValue(i,j,k) + ddt*dt;
// Compute the next time step and store it in the grid
grid.SetValue(i,j,k,n2);
iter++;
}
GetGrid() = grid;
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i n
float n0 = n.GetValue(i,j,k);
float n2 = GetGrid().GetValue(i,j,k) + ddt*dt;
// Compute the next time step and store it in the grid
float n12 = 3.0/4.0*n0 + 1.0/4.0*n2;
grid.SetValue(i,j,k,n12);
iter++;
}
GetGrid() = grid;
iter = GetGrid().BeginNarrowBand();
iend = GetGrid().EndNarrowBand();
while (iter != iend) {
unsigned int i = iter.GetI();
unsigned int j = iter.GetJ();
unsigned int k = iter.GetK();
// Compute rate of change
float ddt = Evaluate(i,j,k);//Beräkna derivatan i n
float n0 = n.GetValue(i,j,k);
float n32 = GetGrid().GetValue(i,j,k) + ddt*dt;
// Compute the next time step and store it in the grid
float n1 = 1.0/3.0*n0 + 2.0/3.0*n32;
grid.SetValue(i,j,k,n1);
iter++;
}
GetGrid() = grid;
}
