Authors:
Nuno T. Reis
;
Vasco S. Costa
and
João M. Pereira
Affiliation:
University of Lisbon, Portugal
Keyword(s):
Rasterization, Ray-Tracing, Ray-Hashing, Ray-Sorting, Bounding-Cone, Bounding-Sphere, Hierarchies, GPU, GPGPU.
Related
Ontology
Subjects/Areas/Topics:
Computer Vision, Visualization and Computer Graphics
;
High-Performance Computing and Parallel Rendering
;
Real-Time Rendering
;
Rendering
;
Rendering Algorithms
Abstract:
We present an algorithm for creating an n-level Ray-Space Hierarchy (RSH) of coherent rays that runs on a
GPU. Our algorithm uses a rasterization stage to process the primary rays, then inputs those results in the RSH
stage which processes the secondary rays. The RSH algorithm generates bundles of rays, hashes them and sorts
them. Thus we generate a ray list containing adjacent coherent rays to improve the rendering performance of
the RSH vs a classical approach. Moreover, scene geometry is partitioned into a set of bounding spheres and,
then, intersected with the RSH to further decrease the amount of false ray bundle-primitive intersection tests.
We show that our technique notably reduces the amount of ray-primitive intersection tests, required to render
an image. In particular it performs up to 50% better in this metric than other algorithms in this class.