This paper introduces a concept of demo arising mainly among people who have common interest in computer graphics and multimedia. The paper shows strong relationship between realtime visualization methods and the subject of this work, so-called demo programs. These programs are the most attractive production produced by community of demo-makers and also the ones most related to conceptual, mathematic and algorithmic fields of computer graphics. Methods used in demo programs varies from simple like „phong“ illumination model, generation of objects from layers, cartoon rendering style or bump-mapping, to complex: realtime ray-tracing, rendering of correct reflections or soft shadows. This work presents six demo programs made by author together with „Nesnausk!“ demo-makers group, also analyses available methods of edge detection and visualization, and describes the method proposed by author, which has distributed calculations between central and video card processors. This method is used as a main visualization effect in „Zenit“ demo program.