void GridForwardEulerDiffusionSolver3::solve(
const ScalarGrid3& source,
double diffusionCoefficient,
double timeIntervalInSeconds,
ScalarGrid3* dest,
const ScalarField3& boundarySdf,
const ScalarField3& fluidSdf) {
auto src = source.constDataAccessor();
Vector3D h = source.gridSpacing();
auto pos = source.dataPosition();
buildMarkers(source.resolution(), pos, boundarySdf, fluidSdf);
source.parallelForEachDataPointIndex(
[&](size_t i, size_t j, size_t k) {
if (_markers(i, j, k) == kFluid) {
(*dest)(i, j, k)
= source(i, j, k)
+ diffusionCoefficient
* timeIntervalInSeconds
* laplacian(src, _markers, h, i, j, k);
} else {
(*dest)(i, j, k) = source(i, j, k);
}
});
}
std::function<double(const Vector3D&)>
CubicSemiLagrangian3::getScalarSamplerFunc(const ScalarGrid3& source) const {
auto sourceSampler = CubicArraySampler3<double, double>(
source.constDataAccessor(),
source.gridSpacing(),
source.dataOrigin());
return sourceSampler.functor();
}
void triangulateAndSave(const ScalarGrid3& sdf,
const std::string& objFilename) {
TriangleMesh3 mesh;
marchingCubes(sdf.constDataAccessor(), sdf.gridSpacing(), sdf.dataOrigin(),
&mesh, 0.0, kDirectionAll);
std::ofstream file(objFilename.c_str());
if (file) {
printf("Writing %s...\n", objFilename.c_str());
mesh.writeObj(&file);
file.close();
} else {
printf("Cannot write file %s.\n", objFilename.c_str());
exit(EXIT_FAILURE);
}
}