The stereotomic apparatus is a 2D projective geometric tool that can be used to construct 3D objects with all planar sides, using principles similar to those used to contruct vanishing point perspectives. This project uses Processing to recreate the apparatus [originally invented in the 17th century] as an interactive Java applet. The object at hand in the view above is a six-sided polyhedron seen in plan [top], elevation [bottom], and unfolded [chartreuse, behind plan]. Adjusting the end points, vanishing points, and fold line changes the proportions, size, and shape of the object while constantly maintaining planarity. Downloadable windows .exe available below, which allows you to output a pdf for printing and reconstruction using paper or some other approximately planar medium.
Middle click or type '3' to toggle 3D view. Hold down right mouse button to zoom, or use the square-bracket keys to zoom in/out. Hold down left mouse button to fly around.