It seems something has changed in the way normals pass from bump nodes out of node groups. In the screen grab below you see a simple import of part 3038 (realistic look, viewport rendered in cycles). I did change the color of the NON-slope faces to be darker, just to make it clear which faces are assigned to which material.
And if I take the bump node from within the "Slope Texture" group and move it out to the top level of the material, you can see that the slope texture appears correctly:
I'm not saying that moving the bump node is the right solution to this problem, but just that it is evidence of where the problem lies.
These screen grabs are from Blender 5.2 LTS, downloaded today.
It seems something has changed in the way normals pass from bump nodes out of node groups. In the screen grab below you see a simple import of part 3038 (realistic look, viewport rendered in cycles). I did change the color of the NON-slope faces to be darker, just to make it clear which faces are assigned to which material.
And if I take the bump node from within the "Slope Texture" group and move it out to the top level of the material, you can see that the slope texture appears correctly:
I'm not saying that moving the bump node is the right solution to this problem, but just that it is evidence of where the problem lies.
These screen grabs are from Blender 5.2 LTS, downloaded today.