I am just wondering if it is possible to create stencil buffer “lighting” in Unity, such as light coming through a window (instead of a shadow with multiply blend mode, have an additive glow to it).
Is the the “light patterns on the floor” effect that you’re looking after, or “light streaks through the air” effect? In both cases I don’t see how they are related to stencil buffers though…
The first one (light patterns on the floor) is simple: just use a spotlight with a cookie. Or Projector with a custom shader that does additive blending.
The second one (light streaks) is usually done by manually creating partially transparent polygons to simulate the “rays”.
Thanks, I am off to the store to buy a Mac 
well, after work that is