After processing, you'll see a new polygon layer.
1. Open the attribute table of the roofs layer.
Let's style the attributes.
3. In the Layers panel click 
to open the Layer Styling panel. Make sure you're styling the roofs layer!
4. Change the renderer from Single Symbol to Graduated.
5. Choose the Aspect field as Value.
6. Choose an appropriate ramp with warmer colours for south-oriented roofs and colder colours to north-oriented roofs.
