sswift: I think he is rendering correctly, the problem is he's not casting from the whole building, so it'll never look right with just the light being cast. If the light's static, then the shadow volume for the building need only be calculated once, so why not use stencil shadows for it anyway?
Also, clip planes work from DX7 onwards and work on pretty much every card out there that has DX7+ drivers. Make sure if you use carmacks reverse that you don't clip any shadow volumes else it screws up the shadows.
halo: In the first pic, are you using 4 lights to cast stencil shadows from?
Excuse my quick mock up of your bulding, but here you go (Blitz3D implementation):
Also, clip planes work from DX7 onwards and work on pretty much every card out there that has DX7+ drivers. Make sure if you use carmacks reverse that you don't clip any shadow volumes else it screws up the shadows.
halo: In the first pic, are you using 4 lights to cast stencil shadows from?
Excuse my quick mock up of your bulding, but here you go (Blitz3D implementation):