By using Cycles, I'd like to create and move a visible light beam with a specific shape, for instance, a pyramid. The beam should interact with other objects, without going through them but producing shadow regions behind them. In other words, I would like to reproduce the behaviour of a light beam impinging on opaque, not reflecting objects. I already created the shape of the beam but I am not able to assign the desired behaviour, i.e., the light behaviour. May you be so kind to help me?