You can also use Geomview to handle the display of data coming from another program that is running simultaneously. As the other program changes the data, the Geomview image reflects the changes. Programs that generate objects and use Geomview to display them are called external modules. External modules can control almost all aspects of Geomview. The idea here is that many aspects of the display and interaction parts of geometry software are independent of the geometric content and can be collected together in a single piece of software that can be used in a wide variety of situations. The author of the external module can then concentrate on implementing the desired algorithm and leave the display aspects to Geomview. Geomview comes with a collection of sample external modules, and the manual describes how to write your own.

Geomview allows multiple independently controllable objects and cameras. It provides interactive control for motion, appearances (including lighting, shading, and materials), picking on an object, edge or vertex level, snapshots in many image file, PostScript, or Renderman RIB format, and adding or deleting objects is provided through direct mouse manipulation, control panels, and keyboard shortcuts.

Geomview supports the following simple data types: polyhedra with shared vertices (.off), quadrilaterals, rectangular meshes, vectors, and Bezier surface patches of arbitrary degree including rational patches. Object hierarchies can be constructed with lists of objects and instances of object(s) transformed by one or many 4x4 matrices. Arbitrary portions of changing hierarchies may be transmitted by creating named references. The full specification for object file formats is in the OOGL (Object Oriented Graphics Language) Reference section of the Geomview manual. If you already have Geomview you might want to try out the OOGL tutorial.

Geomview can be used as a Mathematica graphics output device; this makes viewing Mathematica graphics much more interactive. The same is true for Maple. Geomview began as an effort at the Geometry Center at the University of Minnesota to provide interactive geometry software which is particularly appropriate for mathematics research and education. In particular, Geomview can display objects in hyperbolic and spherical space as well as Euclidean space.