tetra.in

# Tetrahedron, corner at origin, base edge lengths 5

# Face indices 0,1,2,3
# Number of faces
4

# Global vertex indices: 0,1,2,3
# Number of vertices
4

# Vertex coordinates and global vertex indices, for each face
# First three faces congruent isoceles triangles
# Fourth face equilateral triangle side length 5Sqrt[2].
0.0 0.0 1  5.0 0.0 2  0.0 5.0 3
0.0 0.0 1  5.0 0.0 3  0.0 5.0 0
0.0 0.0 2  5.0 0.0 1  5.0 5.0 0
0.0 0.0 3  7.07106781186547550 0.0 2  3.53553390593273730 6.12372435695794510 0

# Gluing instructions for each edge of each face: adj face, local vertex index
# Face 0 glues to faces 2,3,1
# Face 1 glues to faces 0,3,2
# Face 2 glues to faces 0,1,3
# Face 3 glues to faces 0,2,1
2 0
3 0
1 0

0 2
3 2
2 1

0 0
1 2
3 1

0 1
2 2
1 1

# Source face index and local vertex index
0
2