# tetrahedron_slice_movie

tetrahedron_slice_movie, a MATLAB code which displays the intersection of a tetrahedron with a sequence of equally spaced planes that share a common normal vector.

The intersection of a plane and a tetrahedron is a convex planar polygon which is bounded by 0 to 4 points. The possibilities are:

• 0) empty (no intersection);
• 1) a single point;
• 2) a single line segment;
• 3) a triangle;

Given a tetrahedron and a normal vector, the program displays a wireframe image of the tetrahedron, and the points of intersection, and the convex intersection polygon, between the tetrahedron and each of a sequence of equally spaced planes that share the normal vector.

The user defines the tetrahedron by giving a 3x4 vertex array T containing the XYZ coordinates of the vertices.

The user defines the planes by specifying a vector NORMAL which defines the direction normal to the planes.

The program includes an internal switch create_frames which, if set to 1, results in each image being stored in a JPG file, so that a movie file can be created.

### Languages:

tetrahedron_slice_movie is available in a MATLAB version.

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### Source Code:

Last revised on 07 December 2020.