I am using assimp to import 3d models. Assimp defines the following material properties (http://assimp.sourceforge.net/lib_html/materials.html):
- Diffuse color
- Ambient color
- Specular color
- Emissive color
To use with the typical phong shading alghorithm.
I am using a OpenGL 4.3 deferred shading renderer, and I'm wondering how to exactly pass on these proprties between the geometry pass and the shading pass? At the moment I output position, normals and diffuse from geometry pass but those are all used. I've read about somehow packing these values in the alpha component, is that the best approach? Problem is of course i have 4 properties but only 3 alpha components.
Any input is much appreciated.