The gl screensavers and other X11 stuff worked ok. I couldn't find any useful mention of it on the internets until I had a look in jira (openjdk bug system). Came across Monocle which I thought was worth a look. It didn't look all that promising until I saw it was already built-in to the ARM builds.
And ... it worked. Well I guess that's something. I had to add the following to the command line to get javafx working over remote X from an arm box:
I 'fixed' some coprthr peculiarities in the opencl code and got it running (but only on the arm cpu so far):
(Not sure what blogger is doing, it doesn't look that bad even with my shitty palette).
At first the UI was very unresponsive then I discovered that clEnqueueNDRangeKernel or clEnqueueReadBuffer runs synchronously - which is obviously not something to be doing from an animation handler. I chucked that through an Executor and whilst it wont win any land-speed records it is now basically usable.