std::function<Vector3D(const Vector3D&)>
CubicSemiLagrangian3::getVectorSamplerFunc(
const FaceCenteredGrid3& source) const {
auto uSourceSampler = CubicArraySampler3<double, double>(
source.uConstAccessor(),
source.gridSpacing(),
source.uOrigin());
auto vSourceSampler = CubicArraySampler3<double, double>(
source.vConstAccessor(),
source.gridSpacing(),
source.vOrigin());
auto wSourceSampler = CubicArraySampler3<double, double>(
source.wConstAccessor(),
source.gridSpacing(),
source.wOrigin());
return
[uSourceSampler, vSourceSampler, wSourceSampler](const Vector3D& x) {
return Vector3D(
uSourceSampler(x), vSourceSampler(x), wSourceSampler(x));
};
}
void GridForwardEulerDiffusionSolver3::solve(
const FaceCenteredGrid3& source,
double diffusionCoefficient,
double timeIntervalInSeconds,
FaceCenteredGrid3* dest,
const ScalarField3& boundarySdf,
const ScalarField3& fluidSdf) {
auto uSrc = source.uConstAccessor();
auto vSrc = source.vConstAccessor();
auto wSrc = source.wConstAccessor();
auto u = dest->uAccessor();
auto v = dest->vAccessor();
auto w = dest->wAccessor();
auto uPos = source.uPosition();
auto vPos = source.vPosition();
auto wPos = source.wPosition();
Vector3D h = source.gridSpacing();
buildMarkers(source.uSize(), uPos, boundarySdf, fluidSdf);
source.parallelForEachUIndex(
[&](size_t i, size_t j, size_t k) {
if (!isInsideSdf(boundarySdf.sample(uPos(i, j, k)))) {
u(i, j, k)
= uSrc(i, j, k)
+ diffusionCoefficient
* timeIntervalInSeconds
* laplacian3(uSrc, h, i, j, k);
}
});
buildMarkers(source.vSize(), vPos, boundarySdf, fluidSdf);
source.parallelForEachVIndex(
[&](size_t i, size_t j, size_t k) {
if (!isInsideSdf(boundarySdf.sample(vPos(i, j, k)))) {
v(i, j, k)
= vSrc(i, j, k)
+ diffusionCoefficient
* timeIntervalInSeconds
* laplacian3(vSrc, h, i, j, k);
}
});
buildMarkers(source.wSize(), wPos, boundarySdf, fluidSdf);
source.parallelForEachUIndex(
[&](size_t i, size_t j, size_t k) {
if (!isInsideSdf(boundarySdf.sample(wPos(i, j, k)))) {
w(i, j, k)
= wSrc(i, j, k)
+ diffusionCoefficient
* timeIntervalInSeconds
* laplacian3(wSrc, h, i, j, k);
}
});
}
