Hi,
I noticed that node->addShadowVolumeSceneNode (shadowMesh) returns null if I use DeviceNull, is it correct?
I think that the node should be created even by the null device (like other nodes).
I'm using it for unit testing and it's useful that preserves the same behaviour of others devices.
The null device currently doesn't support stencil buffers, hence the shadow is not generated. This can also happen on other drivers if the current setup does not support stencils, so you probably want to cope with that anyway.