Situation: I am using Open3D python,The mesh generation algorithm ( like ball pivot, poisson reconstruction ) are dependent on normal direction. I used estimate_normals and orient_normals_consistent_tangent_plane methods on the point cloud to make sure vertex normals are facing outward. After generating the mesh, i want to check if the face normals are facing outward. If not, I need to flip it.

Help : how to represent "outward" condition for a face normal, mathematically. I can get face normal from mesh.triangle_normals.

context : I am novice engineer, so Any links to theory or examples would help me understand. open3d solution is also welcome :)

Situation: I am using Open3D python,The mesh generation algorithm ( like ball pivot, poisson reconstruction ) are dependent on normal direction. I used estimate_normals and orient_normals_consistent_tangent_plane methods on the point cloud to make sure vertex normals are facing outward. After generating the mesh, i want to check if the face normals are facing outward. If not, I need to flip it.

Help : how to represent "outward" condition for a face normal, mathematically. I can get face normal from mesh.triangle_normals.

context : I am rookie engineer, so Any links to theory or examples would help me understand. open3d solution is also welcome :)