Shader Attribute Descriptors

Each attribute descriptor entry is a Lua table with the following fields:

• name: the name of the attribute/vertex data stream. Must match the name used in GLSL and HLSL code
• type: data type used from the host point of view. One of Shader.DFLOAT, Shader.DBYTE, Shader.DUBYTE, Shader.DSHORT, Shader.DUSHORT or Shader.DINT
• mult: number of components of the input vector
• slot: index of the input slot (HLSL only)
• offset: offset within the input slot (HLSL only, should be 0)

The first three attributes have fixed meaning. Those are, in order:

• the vertex coordinate stream. Type must be Shader.DFLOAT and mult should be 3
• the per-vertex color. Type must be Shader.DUBYTE and mult should be 4
• the texture coordinates. Type must be Shader.DFLOAT and mult should be 2

If one of these fixed attributes is not used by the custom shader program, it should still be defined with a mult value of 0 to serve as a placeholder.