The result of Radiosity calculation is three-dimensional data. Radiosity is calculated first, and then Ray Tracing is rendered using the result. The lighting gradation in the scene is created with the diffuse reflection component and mirror reflection component of two types of light: direct light (the light directly from the light sources) and indirect light (the light reflected on the other objects).(For easier understanding, transparency and refraction are excepted) Radiosity method calculates the diffuse reflection component of the direct and indirect light. On the other hand, Ray Tracing calculates diffuse reflection component and mirror reflection component of the direct light. Therefore, when using them together, the mirror reflection component of the direct light cannot be calculated. Because the diffuse reflection component of the direct light is calculated in both methods, there is no choice for the result to be used.

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1. What is Radiosity ?
2. The Radiosity calculation result doesn't become brighter even though light sources are increased in the scene.
3. What is an important reminder to generate model data for Radiosity calculation ?
4. Why is it a problem, whether front or back of the surface, in Radiosity calculations ?
5. Why some surfaces were displayed as black after Radiosity calculation ?
6. When is the completion point of Radiosity calculation ?
7. How to deal with the texture-mapping or the bump-mapping in Radiosity calculations.
8. What is the relation between Radiosity and Ray Tracing when using them together ?