POLY

POLY - A first step to computer graphics and computational geometry. POLY is a solid modeler system which serves as an experimental tool in education and research for computer graphics and three-dimensional computational geometry. POLY allows to define plane-faced objects through simpler solids or primitives by means of set operations such as union, intersection and difference. Transformations such as translations, rotations, scaling and projections are applicable and a hidden line removal algorithm is used to better visualize the objects. The symbolic description of an object, i.e. a Boolean expression over primitives, is displayed as a binary tree so that objects and subobjects can be uniquely identified and manipulated. Furthermore, POLY’s box of bricks offers a set of exercises such as defining a primitive TORUS in boundary representation, deciding whether or not a point lies inside an object or creating a subobject by performing a Boolean expression over primitives.