In this recipe, we will add some weathering surface attributes by creating another material to represent nail rust running from underneath each slate as though rain has carried it down the roof.
This recipe picks up from the end of the last one. If you have not completed that recipe you can download the start blendfile from the Packtpub website:
Open this file in Blender and continue with the following steps.
We first need to create a new material to provide the rust stains that will be applied in the material node tree. The easiest way to achieve this is to temporarily unlink the current material
slate-roof from our object to create a new one. The ...