The Persistence of Vision Raytracer, or POV-Ray, is a ray tracing program which generates images from a text-based scene description, and is available for a variety of computer platforms. It was originally based on DKBTrace, written by David Kirk Buck and Aaron A. Collins for the Amiga computers. There are also influences from the earlier Polyray raytracer contributed by its author Alexander Enzmann. POV-Ray is free and open-source software with the source code available under the AGPLv3. Many methods for generating the 3-D models are used, including a companion program “moray” for interactive modeling.