// This first set of define allow to say which attributes will be use by the mesh in the vertex and domain shader (for tesselation)
// If we have a layered shader, any UV can be use for this. To reduce the number of variant we groupt UV0/UV1 and UV2/UV3 instead of having variant for UV0/UV1/UV2/UV3
// When UVX is present, we assume that UVX - 1 ... UV0 is present
// This first set of define allow to say which attributes will be use by the mesh in the vertex and domain shader (for tesselation)
// If we have a layered shader, any UV can be use for this. To reduce the number of variant we groupt UV0/UV1 and UV2/UV3 instead of having variant for UV0/UV1/UV2/UV3
// When UVX is present, we assume that UVX - 1 ... UV0 is present