Problems Raspberry Pi2, openFrameworks and VNC

I’ve successfully downloaded/unpacked/ complied OF on my RPi 2 with the latest Raspian Jessie image. The examples I have tried run just fine as long as I have an HMDI monitor connected to the Pi. If I access the Pi via VNC (I’ve tried tightvnc and x11vnc) then the examples launch from a terminal window, but no graphics window appears. Not good, as my application needs VNC .

This has been discussed to some extent in other posts (here and other forums) but I’m still not clear on the cause of this, and whether there is an easy fix. So the Qs:

  1. Is it a matter of getting the right VNC server - I’ve read most versions of VNC do not support hardware accelerated software. Is there a version that does?

  2. If compatibility with hardware acceleration is the problem, could an alternative solution be to switch to Raspian Wheezy and OF 0.8.4 (which I believe does not use hardware acceleration?). My graphics needs are not complex, so could probably cope with a lack of hardware acceleration.

  3. Or is the problem more fundamental? I read a comment that indicated that output from the RPi GPU only goes to the HDMI port. In which case, any form of VNC will fail.

Any thought guys & gurus?

Many thanks

N

@jedahan haven’t you done this?

Mainly, its because oF on the Pi uses dispmanx, which is accelerated. I use https://github.com/patrikolausson/dispmanx_vnc . Unfortunately, there is some mouse/keyboard issues, which I am working on today updating https://github.com/openframeworks/openFrameworks/pull/2990 . If you head over to IRC in about 20 minutes, I can be on and we can try getting it both working together. It would be cool to write a little one-page tutorial for others trying to do this.

Perhaps not applicable to the Raspberry Pi, but the Jetson TK1 has the same issue with GL over VNC and someone on the NV forum has provided steps to get it setup: [HowTo]Install VirtualGL and TurboVNC to Jetson TK1.

Thanks for your efforts, jedahan.

Look forward to the ‘little one-page tutorial’!

@jedahan

How are things going? Any progress?

N

Out of interest, I’ve tried the vnc server at the link suggested by jedahan, but the keyboard does not seem to work at all with a running openFramesworks example (e.g. 3DPrimitivesExample), and the mouse (with two pointers!) freezes or pauses the display when moved. That’s using vnc over ethernet. With wireless, the update rate is very slow, unusable.

So close!

@Nigel yeah, those problems are being addressed in the next oF release. We figured out how to get keyboard and mouse, and it should be fast enough to test that things work, if not actually be very interactive.

When using ethernet, are you connecting directly to your computer, or using you router/switch? With a direct connection, things seem moderately smooth for me.

Yes, I was using a direct ethernet connection between Pi and PC, and with this setup, the examples updated smoothly until the mouse was moved. And as I said, the keyboard didi not work at all. Look forward to seeing the next oF release.