Yevgeniy P. Kuzmin

Color Distribution ‐ A New Approach to Texture Compression

Texture compression is recently one of the most important topics of 3D scene rendering techniques, because it allows rendering more complicated high‐resolution scenes. However, because of some special requirements for these type of techniques, the commonly used block decomposition approach may introduce visual degradation of image details due to lack of colors. We present here a new approach to texture compression, which allows sharing of one color by several blocks providing a larger number of unique colors in each particular block and the best compression ratio. We also present an iterative algorithm for obtaining distributed colors on a texture, and discuss some advantages of our approach. The paper concludes with comparison of our technique with S3TC and other block decomposition methods.

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 models 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.

Ray traversal of spatial structures

This article presents an efficient algorithm for ray traversal of uniform and hierarchical spatial structures. Only simple integer and logical operations are used. The problem of error accumulation during ray casting is considered. The algorithm is well suited for efficient software and hardware implementation.

Modeling with spatial patches

Spatial patches have been introduced (Ivanov and Kuzmin, 2001) as an alternative primitive for the representation of 3D objects potentially acquired from real life. Defined as range images of small regions of an objects surface, they have proven to allow for efficient storage and rendering of such surfaces, and they also exhibit great descriptive capabilities. We present several technologies that we have developed for generating 3D objects represented by spatial patches. These technologies allowed us to convert explicitly defined surfaces, textured polygonal meshes, range images and point clouds to the proposed representation. We also describe how advantageous properties of the new primitive are exploited for efficient reconstruction from range images, discuss the particular problems that we faced during our research, provide many examples to demonstrate the results that we achieved, and conclude with discussion of future work.