Perspective Splatting
Abstract
Splatting is a popular direct volume rendering algorithm that was originally conceived and implemented to render orthographic projections. This paper describes an anti-aliasing extension to the basic splatting algorithm, as well as an error analysis, that make it practical to use for perspective projections. To date, splatting has not correctly rendered cases where the volume sampling rate is higher than the image sampling rate (e.g., more than one voxel maps into a pixel). This situation arises with perspective projections of volumes, as well as with orthographic projections of high-resolution volumes. The result is potentially severe spatial and temporal aliasing artifacts. Some volume ray-casting algorithms avoid these artifacts by employing reconstruction kernels which vary in width as the rays diverge. Unlike ray-casting algorithms, existing splatting algorithms do not have an equivalent mechanism for avoiding these artifacts. In this paper we propose such a mechanism, which delivers high quality splatted images and has the potential for a very efficient hardware implementation. In addition, we analyze two numerical errors that arise with splatted perspective projections of volumes, and describe the rending-time versus image-quality tradeoffs of addressing these errors.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 10, 1999
- Accession Number
- ADA363073
Entities
People
- J. E. Swann Ii
- Klaus Mueller
- Naeem Shareef
- Roger Crawfis
- Torsten Möller
Organizations
- United States Naval Research Laboratory