Any support for stencil buffer?

I was just wondering if there is any type of stencil buffer in Blitzmax? I would like to have some odd shapes textured if possible.

There is a parameter in CreateGraphics to add a stencil buffer but I have no idea how its used.

You can use the stencil buffer if you know how to write your own OpenGL or DX programs. In OpenGL you have full support for writing to the stencil buffer using any geometry you like, and using the stencil to test/discard incoming pixels against based on the stencil values.