I’ve read the GL_ARB_seamless_cube_map extension specification document but I couldn’t understand very well what it does.
As I understood, the extension provides the ability to perform automatic mipmapping on cubemaps, right? This would be useful for creating diffuse and reflection cubemaps in realtime. But I couldn’t think of more uses for this extension.
Perhaps, this extension also allows the GPU to perform correct linear filtering on cube shadowmaps?