Non-Photorealistic Computer Graphics Library

Real-Time Stroke-Based Halftoning

Author(s): Bert Freudenberg.
PhD Thesis: Otto-von-Guericke-Universität, Magdeburg, 2003.
[BibTeX]

Abstract:
This work deals with the non-photorealistic rendering of geometric models. We pursue an approach that combines the expressiveness of stroke-based rendering and the efficiency of halftoning to create a new genre of real-time rendering methods that are applicable to interactive applications such as computer games. Like in traditional halftoning, we create images with black color on a white background. Since strokes are used for shading, we refer to the ensuing methods as stroke-based halftoning. To display strokes for this purpose, we introduce explicit and implicit rendering techniques specifically designed to be accelerated by modern graphics hardware. Explicit techniques determine the geometric extent of strokes before rendering them using vertex programs, while the implicit approaches are based on textures that latently contain stroke information which is revealed in the rendering process. Because outline strokes are important to the visual style created by stroke-based halftoning, methods to render these outlines are developed. Again, both explicit and implicit techniques are introduced. The usability of the new rendering approach is examined in case studies from the fields of archaeological visualization and non-photorealistic game rendering.