Decal shadows are much faster than other shadow methods, and have soft edges; their disadvantage is that they are not animated and are no real shadows.

Z Buffer shadows are a relict from A5 and make the engine unnecessarily complicated. Currently A7 contains 3 kernels, A5, A6, and A7, and I want to get rid of the A5 kernel that is only used for z buffer shadows.

A PSSM shader is planned.

Stencil shadows are slow because they don't use shaders. If the PSSM shader turns out to be not quite the hit, we'll implement shader based stencil shadows as an alternative.

That's what's planned for shadows in the next time.