4.297 Geometric Modeling
Fall 2002
Radiosity Supplemental Handout
Radiosity
Modeling for Radiosity
Radiosity Control Panel
Material | Minimum | Maximum |
Ceramic | 20% | 70% |
Fabric | 20% | 70% |
Masonry | 20% | 50% |
Metal | 30% | 90% |
Paint | 30% | 80% |
Paper | 30% | 70% |
Plastic | 20% | 80% |
Stone | 20% | 70% |
Wood | 20% | 50% |
Typically, the reflectance of a material should never be greater than 85%. this is an unusually high value that will lead to poor-quality renderings. In the real world, even the whitest wall reflects no more than 80% of the light it receives.
Once source of high reflectance can be a map assigned to the material's diffuse component. For example, a white tile bitmap might create high reflectance. In this case, you can reduce reflectance by reducing the RGB Level in the bitmap's Output rollout.
An alternate way to reduce a bitmapped material's reflectance is to set the diffuse color of the material to black, and then reduce the diffuse map's Amount (in the parent material's Maps rollout). You can use this method to reduce the reflectance of 3D procedural maps as well.
Sunlight in Radiosity
Photometric Lights in Radiosity