In Radiosity calculation, light are emitted in the scene from each light source at first. Then, a surface with the maximum non-emitted light energy in the scene is selected, and then the light energy is distributed in the scene. A threshold of rate of the sum of non-emitted light energy against the sum of the initial energy (the rate of the non-emitted energy) can be set as a calculation ending condition in ArchiLumos1.5. However, for the practical purpose, the calculation is manually canceled when the calculation status shows that rendering image is good enough. The rate of non-emitted energy as a guideline for the completion is anywhere from approximately 5 % to 20% depending on scene.

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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 ?