Extrusion and revolution mapping

Abstract

Extrusion, bevel, chamfer, and lathe tools are widely used in a large variety of computer graphics applications such as architectural designs and industrial prototyping of manufactured goods. However, such modeling is usually based on polygonal meshes which often require a considerable amount of graphics primitives. In this article, we present a new image-based approach for rendering extruded and revolved surfaces. We use only a single RGBA texture which stores a binary map (i.e. The profile curve), its Euclidean distance transform, and the two components of the unit gradient vector of the distance fields. All rendering algorithms are based on a ray-tracing procedure performed in texture space. The use of the distance fields allows culling of empty space and thus minimizes the number of ray-tracing steps. The extrusion and revolution mapping techniques produce very convincing models, and both are rendered at interactive frame rates.