I said:
> Sorry, but sharing a DisplayRenderer between two DisplayImpls
> has no relation to sharing scene graphs between two DisplayImpls.
Actually, since DisplayRendererJ3D declares various top-level
noces in the scene graph, it is a logical place to look for
sharing a scene graph between two DisplayImpls. But there will
be very complex issues. For offscreen, you'd need to also look
in the 'if (api == OFFSCREEN)' section of DisplayImplJ3D.initialize(),
and study what the Java3D documentation has to say about
sharing scene graphs between multiple Canvas3Ds. Much easier to
first explore alternate approaches.