Just to make this more complicated, there are bricks that contain both printing and roughness, right? (I'm thinking of the slope brick 33 3x2 parts that have the classic space logo, for example.)
So ideally we want a meta command that let us specify a surface roughness or grit to the "contained" geometry (within the meta command) but such roughness is orthogonal both to part color (set for the whole part) and texturing (because it would be sane to allow the author to build the classic space logo using the new texture extensions.
So ideally we want a meta command that let us specify a surface roughness or grit to the "contained" geometry (within the meta command) but such roughness is orthogonal both to part color (set for the whole part) and texturing (because it would be sane to allow the author to build the classic space logo using the new texture extensions.