pbuffer->bufferedImage

In this presentation:
swinglabs.org/docs/presentations/2007/DesktopMatters/FilthyRichClients.pdf
on slide 59, it is shown how Swing+3d mixing works without the Java2D/OpenGL pipeline.

Can you render something to a pbuffer and get a image out of it somehow?
I would really like to know how to achieve this.

The Screenshot class has methods for reading to a buffered image. That should do what you want I imagine.

http://download.java.net/media/jogl/builds/nightly/javadoc_public/com/sun/opengl/util/Screenshot.html