Distance Field AO quality?

Development Programming & Scripting
1

In this new feature preview, I find that DFAO has been improved a lot since its debut with 4.3.
However, I found that DFAO in my project still looks weird and looks like leaked ink.
Here is the screenshot from engine feature preview thread:

While here is the screenshot of AO visualization in my basic test scene:

I don’t think the quality on my end matches it appears in that preview, and I have tried to increase distance field resolution to 100 and got 128128128 and 4MB size in mesh settings. Also I checked there is no other option to adjust the resolution or the visual. So I want to know if this is it supposed to be, for instance the AO visualization looks different in final image or I did something wrong? I am using 4.10.1. Thanks in advance

2

Hi Netseeker,

There have been some significant changes to DFAO since 4.3 when it was first introduced as you mention. The smoothing in the screenshot you posted from your test scene is expected. Also, in your image you’re comparing the DFAO visualization to the screenshot from a full scene.

You can still go back to the older method for comparison if you would like by using the following console variables:

r.AOGlobalDistanceField 0

r.AOUseSurfaceCache 1

Doing this will go back to the adaptive method used before the smoothing and global distance fields was introduced.

With regards to quality of the DF Resolution Scale a mesh can only be improve to a certain point. For instance, with the chairs, you would probably not notice any increase in the mesh distance field quality beyond 3 or 4.

Give that a shot, and see if that helps give you a better idea between the two methods.

Tim

3

Hi, Tim
Thank you for all those info. After seeing your reply, I did some quick tests using the simple scene that I used to take screenshots above. So here goes my test results:

  1. DFAO visualization:http://i.imgur.com/PZYxyYV.png
    This is the screenshot I’ve shown you above and I make it here just for you to make comparison to check details.
  2. DFAO in scene, not visualization:http://i.imgur.com/oAlIpOl.png
    This is the screenshot that was directly taken in the scene and I think it looks like what visualization shows. I did some tweaks on skylight parameters. By lowering the skylight intensity, DFAO blends better in directly light shadow area but it is not obvious to see the occlusion effect except specular occlusion because lowering skylight intensity makes entire shadowed area too dark.
  3. visualization after disabling global distance field:http://i.imgur.com/7VDpeRp.png
    From what I see, by disabling global distance field, it doesn’t change too much just occludes more areas. I am not sure if this is supposed to work this way.
  4. same setting of scene:http://i.imgur.com/2xVgPIN.png
    Well, it somehow surprises me in scene, I am not sure, but by using “r.AOGlobalDistanceField 0” console command, the result looks smoother, but I don’t know why.
    5.visualization after setting “r.AOUseSurfaceCache 1”:http://i.imgur.com/JMsxfpG.png
    By using surface cache, I think now the DFAO has been set to fully adaptive method. It doesn’t look correct and appears to have AA or sampling issues. Now I do see the improvements here.
  5. fully adaptive method dfao in scene: http://i.imgur.com/f1mX7LR.png
    By comparing with previous screenshot, the difference comes more visible.
    However, I don’t think the newer method is as smooth as it’s shown in new feature preview thread. I am not sure if this is related to my scene setup or something I missed?
    BTW, I will run another test to make a similar scene to make comparison. :slight_smile: