Skip to content

Add solver backup #13

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
nzfeng merged 4 commits into from
Nov 18, 2025
Merged

Add solver backup #13

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
8c58ea6
Add iterative solver backup
nzfeng Oct 29, 2025
7d7b602
Wrap solvers for tet mesh SHM solver
nzfeng Nov 17, 2025
7af3784
Add fallback solvers for 2nd linear solver
nzfeng Nov 18, 2025
763b9db
Fix dumb bugs
nzfeng Nov 18, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 5 additions & 0 deletions include/signedheat3d/signed_heat_3d.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -76,6 +76,11 @@ bool isResolutionValid(const std::array<size_t, 3>& resolution);
std::pair<Vector3, Vector3> computeBBox(VertexPositionGeometry& geometry);
std::pair<Vector3, Vector3> computeBBox(pointcloud::PointPositionNormalGeometry& pointGeom);

Vector<double> solveSquareSystem(SparseMatrix<double>& LHS, const Vector<double>& RHS, bool verbose = false);
Vector<double> solvePositiveDefiniteSystem(SparseMatrix<double>& LHS, const Vector<double>& RHS, bool verbose = false);
Vector<double> solvePositiveDefiniteSystem(SparseMatrix<double>& LHS, const Vector<double>& RHS,
std::unique_ptr<PositiveDefiniteSolver<double>>& solver, bool factorize,
bool verbose = false);
Vector<double> AMGCL_solve(SparseMatrix<double>& LHS, const Vector<double>& RHS, bool& success, bool verbose = false);
Vector<double> AMGCL_blockSolve(const SparseMatrix<double>& L, const SparseMatrix<double>& A,
const SparseMatrix<double>& Z, const Vector<double>& rhs, bool verbose = false);
95 changes: 93 additions & 2 deletions src/signed_heat_3d.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -121,6 +121,97 @@ void setFaceVectorAreas(VertexPositionGeometry& geometry, FaceData<double>& area
}
}

/* A wrapper function around solveSquare, to handle occasional failures of direct solver. */
Vector<double> solveSquareSystem(SparseMatrix<double>& LHS, const Vector<double>& RHS, bool verbose) {
bool success = true;
Vector<double> soln;
try {
soln = solveSquare(LHS, RHS);
} catch (const std::exception& e) {
if (verbose) std::cerr << "Caught exception: " << e.what() << std::endl;
success = false;
}

double solnNorm = soln.norm();
double error = (LHS * soln - RHS).norm();
double tol = 1.0;
if (verbose) std::cerr << "Direct solver residual: " << error << std::endl;
if (std::isinf(solnNorm) || std::isnan(solnNorm) || abs(error) > tol) {
if (verbose) std::cerr << "Direct solver failed, using iterative solver" << std::endl;
success = false;

Eigen::BiCGSTAB<SparseMatrix<double>> solver;
solver.compute(LHS);
soln = solver.solve(RHS);
if (verbose) {
std::cout << "\t#iterations: " << solver.iterations() << std::endl;
std::cout << "\testimated error: " << solver.error() << std::endl;
}
}
return soln;
}

Vector<double> solvePositiveDefiniteSystem(SparseMatrix<double>& LHS, const Vector<double>& RHS, bool verbose) {
bool success = true;
Vector<double> soln;
try {
soln = solvePositiveDefinite(LHS, RHS);
} catch (const std::exception& e) {
if (verbose) std::cerr << "Caught exception: " << e.what() << std::endl;
success = false;
}

double solnNorm = soln.norm();
double error = (LHS * soln - RHS).norm();
double tol = 1.0;
if (verbose) std::cerr << "Direct solver residual: " << error << std::endl;
if (std::isinf(solnNorm) || std::isnan(solnNorm) || abs(error) > tol) {
if (verbose) std::cerr << "Direct solver failed, using iterative solver" << std::endl;
success = false;

Eigen::ConjugateGradient<SparseMatrix<double>, Eigen::Lower | Eigen::Upper> solver;
solver.compute(LHS);
soln = solver.solve(RHS);
if (verbose) {
std::cout << "\t#iterations: " << solver.iterations() << std::endl;
std::cout << "\testimated error: " << solver.error() << std::endl;
}
}
return soln;
}

Vector<double> solvePositiveDefiniteSystem(SparseMatrix<double>& LHS, const Vector<double>& RHS,
std::unique_ptr<PositiveDefiniteSolver<double>>& solver, bool factorize,
bool verbose) {
bool success = true;
Vector<double> soln;
try {
solver.reset(new PositiveDefiniteSolver<double>(LHS));
soln = solver->solve(RHS);
} catch (const std::exception& e) {
if (verbose) std::cerr << "Caught exception: " << e.what() << std::endl;
success = false;
}

double solnNorm = soln.norm();
double error = (LHS * soln - RHS).norm();
double tol = 1.0;
if (verbose) std::cerr << "Direct solver residual: " << error << std::endl;
if (std::isinf(solnNorm) || std::isnan(solnNorm) || abs(error) > tol) {
if (verbose) std::cerr << "Direct solver failed, using iterative solver" << std::endl;
success = false;

Eigen::ConjugateGradient<SparseMatrix<double>, Eigen::Lower | Eigen::Upper> cg;
cg.compute(LHS);
soln = cg.solve(RHS);
if (verbose) {
std::cout << "\t#iterations: " << cg.iterations() << std::endl;
std::cout << "\testimated error: " << cg.error() << std::endl;
}
}
return soln;
}

#ifndef SHM_NO_AMGCL
Vector<double> AMGCL_solve(SparseMatrix<double>& L, const Vector<double>& RHS, bool& success, bool verbose) {

Expand Down Expand Up @@ -152,10 +243,10 @@ Vector<double> AMGCL_solve(SparseMatrix<double>& L, const Vector<double>& RHS, b
std::tie(iters, error) = solve(LHS, RHS, x);
} catch (const std::exception& e) {
if (verbose) {
std::cerr << "Caught exception: '" << e.what() << std::endl;
std::cerr << "Caught exception: " << e.what() << std::endl;
std::cerr << "Use direct solver" << std::endl;
success = false;
}
success = false;
return x;
}
if (verbose) std::cerr << "AMGCL # iters: " << iters << "\tAMGCL residual: " << error << std::endl;
Expand Down
8 changes: 4 additions & 4 deletions src/signed_heat_grid_solver.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -115,9 +115,9 @@ Vector<double> SignedHeatGridSolver::computeDistance(VertexPositionGeometry& geo
#ifndef SHM_NO_AMGCL
bool success;
Vector<double> soln = AMGCL_solve(LHS, RHS, success, VERBOSE);
if (!success) soln = solveSquare(LHS, RHS);
if (!success) soln = solveSquareSystem(LHS, RHS, VERBOSE);
#else
Vector<double> soln = solveSquare(LHS, RHS);
Vector<double> soln = solveSquareSystem(LHS, RHS, VERBOSE);
#endif
// clang-format on
phi = -soln.head(totalNodes);
Expand Down Expand Up @@ -227,9 +227,9 @@ Vector<double> SignedHeatGridSolver::computeDistance(pointcloud::PointPositionNo
#ifndef SHM_NO_AMGCL
bool success;
Vector<double> soln = AMGCL_solve(LHS, RHS, success, VERBOSE);
if (!success) soln = solveSquare(LHS, RHS);
if (!success) soln = solveSquareSystem(LHS, RHS, VERBOSE);
#else
Vector<double> soln = solveSquare(LHS, RHS);
Vector<double> soln = solveSquareSystem(LHS, RHS, VERBOSE);
#endif
// clang-format on
phi = -soln.head(totalNodes);
Expand Down
56 changes: 25 additions & 31 deletions src/signed_heat_tet_solver.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -210,9 +210,9 @@ Vector<double> SignedHeatTetSolver::integrateVectorField(VertexPositionGeometry&
#ifndef SHM_NO_AMGCL
bool success;
Vector<double> Aresult = AMGCL_solve(decomp.AA, combinedRHS, success, VERBOSE);
if (!success) Aresult = solvePositiveDefinite(decomp.AA, combinedRHS); // success
if (!success) Aresult = solvePositiveDefiniteSystem(decomp.AA, combinedRHS); // success
#else
Vector<double> Aresult = solvePositiveDefinite(decomp.AA, combinedRHS);
Vector<double> Aresult = solvePositiveDefiniteSystem(decomp.AA, combinedRHS);
#endif
// clang-format on
phi = reassembleVector(decomp, Aresult, bcVals);
Expand Down Expand Up @@ -256,20 +256,18 @@ Vector<double> SignedHeatTetSolver::integrateVectorField(VertexPositionGeometry&
#ifndef SHM_NO_AMGCL
bool success;
Vector<double> soln = AMGCL_solve(LHS, RHS, success, VERBOSE);
if (!success) soln = solveSquare(LHS, RHS); // direct solver
if (!success) soln = solveSquareSystem(LHS, RHS); // direct solver
#else
Vector<double> soln = solveSquare(LHS, RHS);
Vector<double> soln = solveSquareSystem(LHS, RHS);
#endif
// clang-format on
phi = soln.head(nVertices);
double shift = averageVertexDataOnSource(geometry, phi);
phi -= shift * Vector<double>::Ones(nVertices);
} else {
auto solveDirect = [&]() -> Vector<double> {
if (rebuild || poissonSolver == nullptr) {
if (VERBOSE) std::cerr << "\tFactorizing..." << std::endl;
poissonSolver.reset(new PositiveDefiniteSolver<double>(laplaceMat));
}
auto solveFallback = [&]() -> Vector<double> {
phi = solvePositiveDefiniteSystem(laplaceMat, div, poissonSolver, rebuild || poissonSolver == nullptr,
VERBOSE);
phi = poissonSolver->solve(div);
double shift = averageVertexDataOnSource(geometry, phi);
phi -= shift * Vector<double>::Ones(nVertices);
Expand All @@ -279,9 +277,9 @@ Vector<double> SignedHeatTetSolver::integrateVectorField(VertexPositionGeometry&
#ifndef SHM_NO_AMGCL
bool success;
phi = AMGCL_solve(laplaceMat, div, success, VERBOSE);
if (!success) phi = solveDirect();
if (!success) phi = solveFallback();
#else
phi = solveDirect();
phi = solveFallback();
#endif
// clang-format on
}
Expand Down Expand Up @@ -358,20 +356,18 @@ Vector<double> SignedHeatTetSolver::integrateVectorFieldToFaces(VertexPositionGe
#ifndef SHM_NO_AMGCL
bool success;
Vector<double> soln = AMGCL_solve(LHS, RHS, success, VERBOSE);
if (!success) soln = solveSquare(LHS, RHS);
if (!success) soln = solveSquareSystem(LHS, RHS);
#else
Vector<double> soln = solveSquare(LHS, RHS);
Vector<double> soln = solveSquareSystem(LHS, RHS);
#endif
// clang-format on
phi = soln.head(nFaces);
double shift = averageFaceDataOnSource(geometry, phi);
phi -= shift * Vector<double>::Ones(nFaces);
} else {
auto solveDirect = [&]() -> Vector<double> {
if (rebuild || poissonSolverCR == nullptr) {
if (VERBOSE) std::cerr << "\tFactorizing..." << std::endl;
poissonSolverCR.reset(new PositiveDefiniteSolver<double>(laplaceCR));
}
auto solveFallback = [&]() -> Vector<double> {
phi = solvePositiveDefiniteSystem(laplaceCR, div, poissonSolverCR, rebuild || poissonSolverCR == nullptr,
VERBOSE);
phi = poissonSolverCR->solve(div);
double shift = averageFaceDataOnSource(geometry, phi);
phi -= shift * Vector<double>::Ones(nFaces);
Expand All @@ -381,9 +377,9 @@ Vector<double> SignedHeatTetSolver::integrateVectorFieldToFaces(VertexPositionGe
#ifndef SHM_NO_AMGCL
bool success;
phi = AMGCL_solve(laplaceCR, div, success, VERBOSE);
if (!success) phi = solveDirect();
if (!success) phi = solveFallback();
#else
phi = solveDirect();
phi = solveFallback();
#endif
// clang-format on
}
Expand All @@ -410,11 +406,9 @@ Vector<double> SignedHeatTetSolver::integrateVectorField(pointcloud::PointPositi
case (LevelSetConstraint::None): {
Vector<double> div = vertexDivergence(Yt);

auto solveDirect = [&]() -> Vector<double> {
if (rebuild || poissonSolver == nullptr) {
if (VERBOSE) std::cerr << "\tFactorizing..." << std::endl;
poissonSolver.reset(new PositiveDefiniteSolver<double>(laplaceMat));
}
auto solveFallback = [&]() -> Vector<double> {
phi = solvePositiveDefiniteSystem(laplaceMat, div, poissonSolver, rebuild || poissonSolver == nullptr,
VERBOSE);
phi = poissonSolver->solve(div);
double shift = averageVertexDataOnSource(pointGeom, phi);
phi -= shift * Vector<double>::Ones(nVertices);
Expand All @@ -425,9 +419,9 @@ Vector<double> SignedHeatTetSolver::integrateVectorField(pointcloud::PointPositi
#ifndef SHM_NO_AMGCL
bool success;
phi = AMGCL_solve(laplaceMat, div, success, VERBOSE);
if (!success) phi = solveDirect();
if (!success) phi = solveFallback();
#else
phi = solveDirect();
phi = solveFallback();
#endif
// clang-format on
break;
Expand All @@ -447,9 +441,9 @@ Vector<double> SignedHeatTetSolver::integrateVectorField(pointcloud::PointPositi
#ifndef SHM_NO_AMGCL
bool success;
Vector<double> Aresult = AMGCL_solve(decomp.AA, combinedRHS, success, VERBOSE);
if (!success) Aresult = solvePositiveDefinite(decomp.AA, combinedRHS); // direct solver
if (!success) Aresult = solvePositiveDefiniteSystem(decomp.AA, combinedRHS); // direct solver
#else
Vector<double> Aresult = solvePositiveDefinite(decomp.AA, combinedRHS);
Vector<double> Aresult = solvePositiveDefiniteSystem(decomp.AA, combinedRHS);
#endif
// clang-format on
phi = reassembleVector(decomp, Aresult, bcVals);
Expand Down Expand Up @@ -495,9 +489,9 @@ Vector<double> SignedHeatTetSolver::integrateVectorField(pointcloud::PointPositi
#ifndef SHM_NO_AMGCL
bool success;
Vector<double> soln = AMGCL_solve(LHS, RHS, success, VERBOSE);
if (!success) soln = solveSquare(LHS, RHS); // direct solver
if (!success) soln = solveSquareSystem(LHS, RHS); // direct solver
#else
Vector<double> soln = solveSquare(LHS, RHS);
Vector<double> soln = solveSquareSystem(LHS, RHS);
#endif
#// clang-format on
phi = soln.head(nVertices);
Expand Down
Loading