About Radiosity Calculations

Stopping and Completing the Radiosity Calculation

The radiosity calculation stops when the percentage of remaining data to be calculated, shown by the progress indicator, falls below the value specified in the Convergence text box on the Solution tab.

In the radiosity calculation, surfaces associated with higher energy, such as those that catch rays of direct light, are processed first, followed by surfaces with progressively lower energy. Therefore, the visual changes in the objects or surface development in the window become less conspicuous as the calculation proceeds. Visually check the radiosity calculation's progress in the Radiosity Window and stop the calculation if you decide that it has run far enough.

The percentage shown by the progress indicator is the amount of not-yet-emitted energy compared to the total amount of energy in the scene before the radiosity calculation. The total energy is determined by the objects and lights in the scene. The brightness of an object that receives energy from a light source is determined by that energy. Then that object itself becomes a source of light, transferring its energy to other objects, and so on. In the course of these interactions, the amount of light energy emitted from each object becomes smaller and smaller according to the law of conservation of energy. This energy transfer will continue until the amount of not-yet-emitted energy falls below the percentage specified in the Convergence text box on the Solution tab.

Recalculating Radiosity

The radiosity calculation must be recalculated after changing any of the following: the positional relationship between objects and light sources, light settings, the surface attributes of objects, or an object's level of subdivision, or after performing a transformation. Radiosity does not need to be recalculated after only modifying camera settings.

Note Radiosity Pro, included with Shade3D Professional, uses dimming to eliminate the need to recalculate radiosity after changing the position, intensity, or color of lights in some cases.

See also Radiosity Pro