Author Topic: Corona 5 - 2.5D Displacement on Curves  (Read 16268 times)

2019-11-19, 11:49:23
Reply #45

romullus

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Displacement is at 1px in both cases.

You need to set lower screen size in 2.5D displacement, or higher in classic one, to get comparable results. If i'm not mistaken, the ratio is about 1:1,5 So 1px classic displacement, should have about the same quality as 0,67px 2.5D displacement.
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2019-11-19, 14:00:00
Reply #46

matsu

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Hey Matsu, what is the topology of your plane? Is it equally subdivided, can you please provide a wireframe?

It's a plane primitive 3x3m, 30x30 division (+Noise modifier Scale=20 Strength Z=60mm) - so 100x100mm squares. Adding wireframe.

Quote from: romullus
You need to set lower screen size in 2.5D displacement, or higher in classic one, to get comparable results. If i'm not mistaken, the ratio is about 1:1,5 So 1px classic displacement, should have about the same quality as 0,67px 2.5D displacement.

Adding comparison on 0.5px. The artifact is still there, but not as pronounced.

2019-11-19, 14:16:05
Reply #47

GeorgeK

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Hey Matsu, what is the topology of your plane? Is it equally subdivided, can you please provide a wireframe?

It's a plane primitive 3x3m, 30x30 division (+Noise modifier Scale=20 Strength Z=60mm) - so 100x100mm squares. Adding wireframe.

Quote from: romullus
You need to set lower screen size in 2.5D displacement, or higher in classic one, to get comparable results. If i'm not mistaken, the ratio is about 1:1,5 So 1px classic displacement, should have about the same quality as 0,67px 2.5D displacement.

Adding comparison on 0.5px. The artifact is still there, but not as pronounced.

So yeah everything seems fine I suspect the usage of noise modifier with 2.5D, I will test this a bit further to see bad it can get, thanks.
George Karampelas | chaos-corona.com
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2019-11-19, 15:20:39
Reply #48

matsu

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I've tried with and without noise mod; with different textures; RWS and not - it persists. Even tried world size displacement.

But I think it's strange you get this obvious repeating/tiling pattern. With the old displacement you could just lower the quality - sure, you'd lose detail, but you wouldn't get artifacts like this. If you can reproduce it, I hope you can sort it out.

2019-11-27, 23:30:36
Reply #49

dj_buckley

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Just wondered if there was any progress with this.

I think my biggest question is which displacement is correct in terms of depth.

Tesselated geometry seems to give more definition to the displacement - when you look at my tests and can see untesselated next to tesselated.  It makes the untesselated surface look quote flat.

So is untesselated correct in terms of depth.

Or

Is tesselated correct in terms of depth, but incorrect with regards artifacts?

2020-09-08, 11:10:48
Reply #50

dj_buckley

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Just bumping this back up to see if anything was addressed on this for Corona 6.  I'm testing at the minute and it still seems to be an issue.  Would be good to get an update

2020-09-08, 11:34:48
Reply #51

PROH

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Agree. I often need to go back to the "old" displacement method, because 2.5D gives to many artifacts. Sometimes tesselation before displacement helps, but not always.

Would be great to see a fix for this.

Regards

2020-09-08, 11:58:37
Reply #52

agentdark45

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Agree. I often need to go back to the "old" displacement method, because 2.5D gives to many artifacts. Sometimes tesselation before displacement helps, but not always.

Would be great to see a fix for this.

Regards

I ran into this issue the other day, it occurred on a curved wall that had a fine ribbed wavy displacement map applied to it. 2.5D displacement produced massive "spiky" black artefacts so had to go back to the old method with 1px displacement resolution...needless to say RAM usage and pre-computation time went through the roof. Increasing the tessellation of the curved wall didn't help in removing the artefacts.
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2020-09-08, 12:19:04
Reply #53

dj_buckley

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I think you guys have answered my question :)

Still stuck with old displacement and no progress has been made.


2020-09-08, 12:49:57
Reply #54

GeorgeK

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Just bumping this back up to see if anything was addressed on this for Corona 6.  I'm testing at the minute and it still seems to be an issue.  Would be good to get an update

Further optimization and bug fixing for 2.5D Displacement will be looked into for the Corona version 7.0 release. Please rest assured that we will inform you of any further developments.

Thanks.
George Karampelas | chaos-corona.com
Chaos Corona QA Specialist | contact us

2020-09-08, 20:30:25
Reply #55

Alexandre Besson

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Same thing here, edge's atefacts present with classic displacement and heavier with 2.5D.
Chamfer and some centimeters dispacement per exemple create massive edge's atefacts. no usable with chamfer edges, annoying.

Regards

2021-02-26, 15:31:34
Reply #56

rowmanns

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Hi Guys,

We have greatly improved the 2.5d displacement tessellation in the latest v7 daily build.

It should remove a great deal of the artifacts which were caused by the 2.5d displacement. You can find a build here: https://forum.corona-renderer.com/index.php?topic=30876.msg182287#msg182287

I will look forward to your feedback.

Cheers,

Rowan
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2021-02-26, 15:35:33
Reply #57

dj_buckley

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Sounds good.  Do you have before and after examples?  I'd be wary of upgrading personally considering you've removed the old displacement (if I've read correctly) and I'm mid project.  It also concerns me slightly that you use the terms 'should' and 'great deal' rather than 'does' and 'all'.

Out of interest why are you removing the old one?

2021-02-26, 16:22:30
Reply #58

rowmanns

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Hi,

I'd say that it would be risky upgrading to any daily build mid project ;). We try hard to ensure they are as stable as possible, but they are always a use at your own risk kind of deal. More info about them can be found here: https://coronarenderer.freshdesk.com/support/solutions/articles/5000570015

Here are a couple of examples (also in the changelog):
https://corona-renderer.com/comparer/6mFx83
https://corona-renderer.com/comparer/ZkCZyt

I used those terms because we cannot test and guarantee 100% of scenarios, I'd rather err on the side of caution rather than promise the world :)

It was always planned to remove the old displacement once we felt that the 2.5d displacement was capable of taking over, due to it's quicker calculation speed, lower memory usage and now more comparable quality. It is also very time consuming to maintain and ensure compatibility with two types of displacement, so this enables us to focus more on other features too.

I hope this information is useful.

When you do get a chance to test this, I will be interested to hear your feedback.

Rowan
« Last Edit: 2021-02-26, 16:31:17 by rowmanns »
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