SSAOFilter "Flickering" problem?

I’m looking at the SSAOFilter test app, and there seems to be a problem with “flickering”. I wondered if anyone else has seen this issue, and whether there is a workaround?

To repro: Startup, move close to the “Potted Plant” hanging on the left wall (or any surface, really), then look around slightly. You’ll see all the shadows start to flicker as you move the mouse around.

Is this a problem with my specific (probably crappy) video hardware?

EDIT: I’m using a nightly build, not sure which version. And my machine is a 13" Macbook Pro (ie: not fantastic graphics card).

I can see some pattern in the shadows because of the way samples are computed, but I don’t really see any filckering.

Could you upload a video of what you see?

Working on it. I think what’s happening is that the SSAO technique is shooting rays out “randomly”, and some of those rays would normally be hitting surfaces outside the frustum. The flickering and flowing is most noticeable at the edges of the viewport. And even more noticeable when you move the camera “up close and personal” with a very shaded area (such as the potted plant).

For maximum effect:

  • “turn off” the normal and diffuse map textures (comment out line 68 and 69 in TestSSAO).
  • Move the camera close to the potted plant on the left side of the scene.
  • Pitch and yaw the camera around (just moving the mouse), and keep an eye on the edges of the viewport.

Yes that artifact is inevitable (at least with current implementation). It’s even more noticeable if you have a wide radius.
Lowering the radius and/or the ssao intensity will help to make it less noticeable. Also with a fully shaded scene it’s even less unnoticeable.

Okay, I’ll give that a try. Here’s the video, BTW (better late than never?): JME3 SSAOFilter flickering on Vimeo . Sorry, no sound.

Ok that’s what I thought.
Lowering the radius will help a lot.