Adding THREE.OverlayOperation
Adding lightMapMode and envMapMode
Preparing to use the OverlayOperation in lightmap shaders
Hardcoding lightmap overlay params for now
The lightMapMode needs to be part of the code chunks
Updating shaders for new lightMapMode defines
Adjusting WebGLProgram to work with lightMapMode
Adjusting examples for lightMapMode
Use THREE.BoxGeometry in lightMapMode sample
Adding additive lightMapMode