thanks for the info. This would mean that the material setting would produce the constants - and that, inside the shade operations, I could refer to them. Assume I would set something to the diffuse color values, it would take what I set in the material definition. Right?

Since I see that you are really intrigued with shader development, a more personal questionwhy: DirectX allows the read-in of *.fx files. So theroetically itr would be possible to let DirectX do all this.
It's a while ago that I implemented an x.file (the teapot sample from DirectX) and brought it into the render pipeline. So this would be an option, wouldn't it?