Casting Shadows in Papervision 3D. V.1
Andy Zupko’s class will let you cast the shadow of any object onto any plane that has a MovieMaterial. It’s a unique method which enables casting precise shadows onto a plane. The plane is singled out here because if you do anything other than a plane it will be much heavier on the CPU.
This technique is very fast – since you know the dimensions of a plane, you can easily determine the UV coordinates of a plane/ray intersection – without having to riddle through faces and checking sides of triangles. The author requires a MovieMaterial because it makes it very easy to do cool stuff with the shadow: Blend/Alpha/Filters – you can apply all these things to your shadow.
Great material base and detailed comments make this article quite educational and enjoyable. There are two demos available: Cow and Monster.You can donwload both the ShadowCaster class and cow demo source.