Name
Abstract | ||
|---|---|---|
Real-time shading using general (e.g., anisotropic) BRDFs has so far been limited to a few point or directional light sources. We extend such shading to smooth, area lighting using a low-order spherical harmonic basis for the lighting environment. We represent the 4D product function of BRDF times the cosine factor (dot product of the incident lighting and surface normal vectors) as a 2D table of spherical harmonic coefficients. Each table entry represents, for a single view direction, the integral of this product function times lighting on the hemisphere expressed in spherical harmonics. This reduces the shading integral to a simple dot product of 25 component vectors, easily evaluatable on PC graphics hardware. Non-trivial BRDF models require rotating the lighting coefficients to a local frame at each point on an object, currently forming the computational bottleneck. Real-time results can be achieved by fixing the view to allow dynamic lighting or vice versa. We also generalize a previous method for precomputed radiance transfer to handle general BRDF shading. This provides shadows and interreflections that respond in real-time to lighting changes on a preprocessed object of arbitrary material (BRDF) type. |
Year | Venue | Keywords |
|---|---|---|
2002 | Rendering Techniques | lighting coefficient,lighting environment,area lighting,non-trivial brdf model,spherical harmonic,incident lighting,arbitrary brdf shading,product function time,product function,low-frequency lighting,general brdf shading,brdf time,dynamic lighting,graphics hardware,low frequency,production function,real time |
Field | DocType | ISBN |
Bidirectional reflectance distribution function,Computer vision,Per-pixel lighting,Spherical harmonic lighting,Computer graphics (images),Computer science,Spherical harmonics,Artificial intelligence,Precomputed Radiance Transfer,Dot product,Normal,Shading | Conference | 1-58113-534-3 |
Citations | PageRank | References |
75 | 3.61 | 19 |
Authors | ||
3 | ||
Name | Order | Citations | PageRank |
|---|---|---|---|
| Jan Kautz | 1 | 3615 | 198.77 |
| Peter-Pike Sloan | 2 | 796 | 45.22 |
| John Snyder | 3 | 2579 | 172.17 |