dumping from a jit.pwindow into a jit.matrix

I need to extract the contents of the pwindow into a matrix and then send it to a higher-level window in the patch (which already has a jit.world...).

Alternatively, I need to know where the final image is being generated so I can capture it as a jit.matrix.

The goal is for the resulting image to be usable at higher levels of the patch.