Shading model of side fins (or similar objects) next to a window where hWin is the window height, wWin is the window width, gap equals the horizontal distances between the window edges and the side fins, dep fin length in the direction normal to the window.
This model computes a simplified view factor of the side fins. The view factor determines how much diffuse light is blocked by the fins. We assume that the fins do not reflect light towards the window.