// STEP I-3.
double[] SolveHeat()
{
double init_heat = (double)System.Math.Sqrt(W * H) / 64.0;
double[] b_heat_sparse = new double[area_cnt];
double[] u_heat_sparse = new double[area_cnt];
int voxid_init = GetVoxelIndex(i0, j0);
int matid_init;
if (Voxel2Matrix.TryGetValue(voxid_init, out matid_init))
{
b_heat_sparse[matid_init] = init_heat; // the point of initial seed
}
solver_heat.Solve(b_heat_sparse, u_heat_sparse);
return(u_heat_sparse);
}
// STEP III-3.
double[] SolveDistance(double[][] X_sparse)
{
////////////////////////////////////////////////////////////
// divergence of normalized gradient X
// [CAUTION] NEGATED value to fit Cholesky decomposition
////////////////////////////////////////////////////////////
double[] b_dist_sparse = new double[area_cnt];
// change for loop based on sparse
for (int matid_this = 0; matid_this < area_cnt; matid_this++)
{
List <int> matid_neighbor;
if (!MatrixNeighbors.TryGetValue(matid_this, out matid_neighbor))
{
continue;
}
double div_x = 0.0;
double div_y = 0.0;
bool bound_x0 = false;
bool bound_x2 = false;
if (matid_neighbor[0] != -1)
{
div_x -= X_sparse[0][matid_neighbor[0]];
}
else
{
bound_x0 = true;
}
if (matid_neighbor[1] != -1)
{
div_x += X_sparse[0][matid_neighbor[1]];
}
else
{
bound_x2 = true;
}
if (bound_x0 || bound_x2)
{
div_x *= 2.0;
}
bool bound_y0 = false;
bool bound_y2 = false;
if (matid_neighbor[2] != -1)
{
div_y -= X_sparse[1][matid_neighbor[2]];
}
else
{
bound_y0 = true;
}
if (matid_neighbor[3] != -1)
{
div_y += X_sparse[1][matid_neighbor[3]];
}
else
{
bound_y2 = true;
}
if (bound_y0 || bound_y2)
{
div_y *= 2.0;
}
b_dist_sparse[matid_this] = -0.5 * (div_x + div_y); // NEGATED!
}
////////////////////////////////////////////////////////////
// solve distance field
////////////////////////////////////////////////////////////
double[] phi_sparse = new double[area_cnt];
solver_dist.Solve(b_dist_sparse, phi_sparse);
double phi_max = phi_sparse.Max();
double phi_min = phi_sparse.Min();
double[] phi_dense = new double[W * H];
for (int matid_this = 0; matid_this < area_cnt; matid_this++)
{
int voxid_this;
Matrix2Voxel.TryGetValue(matid_this, out voxid_this);
phi_dense[voxid_this] = phi_sparse[matid_this] - phi_min;
}
return(phi_dense);
}