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View Full Version : LW 11.6 Depth Buffer AA - Not working



tcoursey
11-01-2013, 09:39 AM
What am I doing wrong... I pull up Render Globals and under the Render tab check the box Depth Buffer AA. Then under Compositing Buffer Export in the Image Processing -> Image Filter area I check Depth as the buffer I want and then under options of that plugin I select option for Either - None - Blurry - Medium - Sharp - Sharpest. None seem to offer any different result.

zardoz
11-01-2013, 10:00 AM
well, in most places you will find that people say that the depth buffer shouldn't have AA, so I guess the filter shouldn't be an issue.

tcoursey
11-01-2013, 10:03 AM
Fair enough, but if it's a feature then it should work. When I've tested non AA depth buffers to use for DOF post processing I've always been less than satisfied as there are ghosting effects from such a sharp jagged depth buffer.

Kray does Depth Buffer AA, and although I have not tested or used it, have seen images that have used post processing with the dpeth buffer and the results are quite nice.

So I ask again, for anyone that might know....this new feature of AA a depth buffer, how should we engage it! The manual was followed to the T as best I can tell, and yet no change in results.

Thanks.

tcoursey
11-02-2013, 04:37 PM
anyone with thoughts on what I'm missing here. The Depth buffer does not seem to be AA when options are selected...at least not like KRAY does. Very clean AA output there.

BeeVee
11-04-2013, 04:20 AM
Do you have antialiasing for the render?

B

Thomas Leitner
11-04-2013, 04:55 AM
So I ask again, for anyone that might know....this new feature of AA a depth buffer, how should we engage it! The manual was followed to the T as best I can tell, and yet no change in results.


All you need to do is to enable it in the Render Globals.
Maybe itīs what Ben said. But also consider that only the edges in front of an object gets AA in the depth channel, not in front of nothing.
I donīt know which version you use but it works in 11.5 and we have used it in a previous version, too.

But again: to get usable results with post DOF you shouldnīt use AA for the depth buffer at all. The shade of gray determines the distance for the post effect ( an AA pixel means a wrong distance for the effect). And use a floating point file format for storage the depth buffer.

ciao
Thomas

tcoursey
11-04-2013, 09:23 AM
I will look into it further and post some results I'm getting. Yes I have AA on the render. I use Adaptive sampling, is that an issue? I use min 1 and max 30-60 typically under AA samples. The only option I see for the AA is a bilinear filter. Is that the actual AA? I'll post results later... Maybe someone can shed some light for me.

I guess if AA isn't needed or useful on depth maps, why would NT add it as feature? Other use maybe?

Thomas Leitner
11-04-2013, 10:23 AM
....Yes I have AA on the render. I use Adaptive sampling, is that an issue? I use min 1 and max 30-60 typically under AA samples....

No, Adaptive sampling is ok.
Check this:

117968

You can see the AA only in front of geometry.

ciao
Thomas

tcoursey
11-04-2013, 10:45 AM
So it appears to be an anti-aliasing issue. I typically use Adaptive sampling as LW is excellent at deciding what to AA in my opinion and experience. However in this case it appears that it's not. The sharp edges of the depth buffer are getting the same decision as the color channels and are not the best choice. If I do a non-adaptive AA pass the render is much cleaner and does seem to have AA on the depth buffer. The higher the sample rate I'm sure it would get the image just as clean as the Kray test I show as well.

May not be an issue of sorts, but possibly disappointing in some respects, for me. Love Adaptive sampling in LW....but not for this use.

117969