Global illumination - yvt/openspades GitHub Wiki

With default settings, OpenSpades does a simple ambient occlusion. When an option called Lighting is set to High or r_radiosity is set to 1, OpenSpades uses additional method to simulate global illumination:

• Raytraced Ambient Occlusion (to compute shadow of the sky light)
• Reflective Shadow Maps (to compute the second reflection of the sun light)

Real global illumination, however, generates subtle, but also important effects that are mandatory to achieve realism. -- Reflective Shadow Maps [Dachsbacher05]