TriangleMeshDistance

Header only*, single file, simple and efficient C++11 library to compute the signed distance function to a triangle mesh.

The distance computation to the triangle collection is accelerated with a sphere bounding volume hierarchy. The sign of the distance is resolved with the method presented in "Generating Signed Distance Fields From Triangle Meshes" by Bærentzen, Andreas & Aanæs, Henrik. (2002).

* Depends on Eigen

// Declare mesh vertices and triangles
std::vector<std::array<double, 3>> vertices;
std::vector<std::array<int, 3>> triangles;

// (... fill the `vertices` and `triangles` with the mesh data ...)

// Initialize TriangleMeshDistance
tmd::TriangleMeshDistance mesh_distance(vertices, triangles);

// Query TriangleMeshDistance
tmd::Result result = mesh_distance.signed_distance({ x, y, z });

// Print result
std::cout << "Signed distance: " << result.distance << std::endl;
std::cout << "Nearest point: " << result.nearest_point << std::endl;
std::cout << "Nearest entity: " << result.nearest_entity << std::endl;
std::cout << "Nearest triangle index: " << result.triangle_id << std::endl;

• The input triangle mesh must be fully connected and watertight. Triangle soups and meshes with holes will return the correct distance but the sign will be undefined.
• TriangleMeshDistance keeps a copy of the vertex and triangle data.
• The pseudonormals required to compute signed distances are calculated and stored at building time.
• TriangleMeshDistance can be declared empty and constructed multiple times with different meshes. If the new mesh needs less memory than the curent one, memory allocations will be avoided.