I currently use a set of volume textures to encode 3rd order RGB SH coefficients. This allowed me quickly have a convincing diffuse lighting on the animated entities in my project. As the lighting in smooth enough, the SH encodes both direct & indirect lighting with good enough results.
I also experimented with SH for other purposes :
- obtaining convincing specular colors. The preliminary results were interesting but I lacked time to properly integrate this feature.
- obtaining lighting for volumetric lighting effects. While I managed to have some nice atmospheric effects, this method is not directly applicable to reconstruct clearly visible "light beams". Moreover, the ray marching code in fragment shader is quite costly, so for now, I discarded it.
- lighting vegetation planes. This is a nasty hack, but the vegetation now have a subtle view dependent lighting that contributes to reduce a tiling effect ; and the vegetation now better integrates with surrounding geometry.