BRDF-Constrained Optimal Facet Subdivision Algorithm Development: Phase I Final Report
Abstract
Report developed under SBIR contract DAAEO7-97-C-X014. In the visual spectral region, reflection dominates the optical signatures of vehicles. Rendering of facetted models is made difficult by the presence of specular reflections, e.g., glints, which exhibit extreme sensitivity to surface orientation. The difficulty is compounded by the coarseness of the facetizations used in three-dimensional modeling. In a Phase I Small Business Innovation Research effort a new algorithm has been developed to reduce the errors in rendering specular glints without unnecessarily increasing the number of facets and hence the computational burden. The algorithm subdivides facets until the angular separations of vertex normals is comparable with the width of the specular lobe of the bidirectional reflectance distribution function used to represent the surface reflectivity. Sample results for an ellipsoid whose surface reflectivity is characterized with the Sandford-Robertson BRDF model are presented. The algorithm was developed in the context of a new tool for visualizing faceted vehicle models. This prototype tool, which includes a GUI to visualization, is also discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1997
- Accession Number
- ADA358423
Entities
People
- John G. Devore