Spatial Patches ‐ A Primitive for 3D Model Representation

The commonly used solution for real‐life 3D model representation is polygonal spatially consistent geometry, with texture, and, optionally, bump or displacement maps attached. Although the idea of displacement mapping is well known, there are just a few approaches to its efficient implementation. In this paper we develop a technique that allows for efficient representation and rendering of 3D models by getting a new angle on the displacement mapping concept. We introduce a new primitive that is defined as the range image of a small part of the model's surface; therefore, it is called a spatial patch. The whole model is just a collection of patches with no connectivity information between them. Such a representation can be directly acquired by 3D scanning machinery, and stored in a compact uniform form. It also allows for efficient visualization, which is the major focus of this paper. Thus, we present the logical structure of a rendering unit based on conventional z‐buffering, and discuss the involved algorithms in detail. These algorithms benefit from modern features of computing units for which we believe the proposed technique can be used in a wide range of applications dealing with real‐life 3D data.