Author Topic: Artifacts- Atmo appears through terrain  (Read 14658 times)

Offline choronr

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Artifacts- Atmo appears through terrain
« on: February 17, 2009, 05:38:48 PM »
While rendering a new scene, I see two artifacts where it appears that the atmosphere is showing through the terrain. I've attached the file for your information. Would appreciate any thoughts you may have. Thanks.

Offline Tangled-Universe

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Re: Artifacts- Atmo appears through terrain
« Reply #1 on: February 17, 2009, 06:46:52 PM »
When I render a crop of the horizon I don't see any problems with atmosphere showing through terrain.
Is it on other areas?
Perhaps you could show a screencapture of the problem? Would save me a lot of time :)

In general when the atmo is showing through the terrain it helps to enable raytracing in the atmosphere node. I see you haven't enabled that, so that might help.
But, be sure of this, since it will at least double your rendertime, if not triple.

Martin

Offline PG

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Re: Artifacts- Atmo appears through terrain
« Reply #2 on: February 17, 2009, 07:01:55 PM »
Just adding to what Martin said, checking do reverse primary rays seems to do the trick as well with an apparent smaller performance hit.
Figured out how to do clicky signatures

Offline choronr

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Re: Artifacts- Atmo appears through terrain
« Reply #3 on: February 17, 2009, 07:08:44 PM »
Thanks T-U and PG. I had just run into a monitor issue (not related to the problem). As soon as I can fix it, I'll get back here with the image.

Offline Tangled-Universe

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Re: Artifacts- Atmo appears through terrain
« Reply #4 on: February 17, 2009, 07:34:58 PM »
Just adding to what Martin said, checking do reverse primary rays seems to do the trick as well with an apparent smaller performance hit.

You mean it helped in this case? I find it difficult to believe/understand.
This is what's known so far about the "do reverse primary rays":

http://forums.planetside.co.uk/index.php?topic=5092.msg52714#msg52714

Could be that things are being traced differently, hence 'reverse', but it remains still unclear.

Martin

Offline choronr

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Re: Artifacts- Atmo appears through terrain
« Reply #5 on: February 17, 2009, 07:38:06 PM »
Here is the .jpg of the image. Note the 'white' artifacts in the upper terrain - both to the right and the left.

Offline Tangled-Universe

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Re: Artifacts- Atmo appears through terrain
« Reply #6 on: February 17, 2009, 07:39:48 PM »
Here is the .jpg of the image. Note the 'white' artifacts in the upper terrain - both to the right and the left.

Haha, ok...I had the cloudlayer switched off for speed-reasons ;D
I'll take a look at it again :)

Offline Tangled-Universe

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Re: Artifacts- Atmo appears through terrain
« Reply #7 on: February 17, 2009, 08:14:37 PM »
I also noticed you have detail blending set @ 1.25...for still images detail blending is hardly necessary, though it is very important for animation.
If you set it to 0 it won't affect the result very little and it will render a lot faster :)

Offline choronr

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Re: Artifacts- Atmo appears through terrain
« Reply #8 on: February 17, 2009, 08:15:57 PM »
Thanks T-U, I'll give it a try and get back to you.

Offline Tangled-Universe

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Re: Artifacts- Atmo appears through terrain
« Reply #9 on: February 17, 2009, 08:21:35 PM »
Ok, I reproduced the artifact.

1) reverse primary rays resulted in a black sky (as reported by other users). The clouds pinching through the terrain are replaced by black pixels, looking like gaps in the displacements.

2) raytraced shadows in the atmosphere node didn't help either (interesting!!)

Will get back to you if I know more...

Offline choronr

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Re: Artifacts- Atmo appears through terrain
« Reply #10 on: February 17, 2009, 08:29:52 PM »
Ok T-U, now crop rendering on your previous suggestion...

Offline choronr

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Re: Artifacts- Atmo appears through terrain
« Reply #11 on: February 17, 2009, 08:31:25 PM »
I also noticed you have detail blending set @ 1.25...for still images detail blending is hardly necessary, though it is very important for animation.
If you set it to 0 it won't affect the result very little and it will render a lot faster :)
Set detailed blending to 0 and still get the artifacts.

Offline Tangled-Universe

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Re: Artifacts- Atmo appears through terrain
« Reply #12 on: February 17, 2009, 08:37:40 PM »
It was not meant as a suggestion for solving your problem, but as a suggestion in general for rendering :)
Setting up the renderer this way makes your rendertimes unnecessary long, think this setting will save you in this case at least 50% of the time.
Also, I saw you have a compute terrain, then base colours and then a compute normal which isn't needed at all. Remove it, and save even more rendertime :)

I just used the setting "raytrace everything" and that works, but the terrain looks really messed up now.
I think this is a bug we're dealing with. First the clouds sticking through and secondly the odd results using raytracing on everything.

Martin

Offline choronr

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Re: Artifacts- Atmo appears through terrain
« Reply #13 on: February 17, 2009, 08:43:40 PM »
Well that is a good observation if in fact it is a bug. I will have to go into PS or Paint.net and fix the image for later posting. Would appreciate hearing from you or Oshyan on your findings ...thanks again Martin.

Offline Tangled-Universe

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Re: Artifacts- Atmo appears through terrain
« Reply #14 on: February 17, 2009, 08:55:08 PM »
Could you also check if enabling "raytrace everything" works for getting rid of the clouds, but results in a messed up terrrain?

 

anything