UCT CS Research Document Archive

Accelerating Ray Shooting Through Aggressive 5D Visibility Pre-processing

Sharpe, Adrian, Matthew Hampton, Shaun Nirenstein, James Gain and Edwin Blake (2003) Accelerating Ray Shooting Through Aggressive 5D Visibility Pre-processing. In Proceedings 2nd International Conference on Computer Graphics, Virtual Reality, Visualisation and Interaction in Africa (AFRIGRAPH 2003), pages 95-100, Cape Town.

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We present a new approach to accelerating general ray shooting. Our technique uses a five-dimensional ray space partition and is based on the classic ray-classication algorithm. Where the original algorithmevaluates intersection candidates at run-time, our solution evaluates them as a preprocess.

The offline nature of our solution allows for an adaptive subdivision of ray space. The advantage being, that it allows for the placement of a user set upper bound on the number of primitives intersected.

The candidate sets produced account for occlusion, thereby reducing memory requirements and accelerating the ray shooting process. A novel algorithm which exploits graphics hardware is used to evaluate the candidate sets. It is the treatment of occlusion that allows for the practical precomputation of the ray space partition. This algorithm is called aggressive since it is optimal (no invisible primitives are included), but may result in false exclusion of visible primitives. Error is minimised through the adaptive sampling.

EPrint Type:Conference Paper
Keywords:Visibility, Ray-tracing, Graphics Hardware
Subjects:I Computing Methodologies: I.3 COMPUTER GRAPHICS
ID Code:47
Deposited By:Nirenstein, Shaun
Deposited On:23 September 2003
Alternative Locations:http://people.cs.uct.ac.za/~snirenst/p95-sharpe.pdf, http://doi.acm.org/10.1145/602330.602348