Author Topic: Corona 5 - 2.5D Displacement on Curves  (Read 4510 times)

2019-11-07, 14:48:08

dj_buckley

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Anyone know why my displacement goes funky when it reaches a curve?  The exact same material on both the flat surface and the curve?

2019-11-07, 14:58:36
Reply #1

romullus

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Did you try to switch to classic displacement and see if artefacts are gone?
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2019-11-07, 15:11:27
Reply #2

dj_buckley

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Artifacts remain albeit not as extreme

2019-11-07, 15:25:39
Reply #3

romullus

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Could it be that they are only visible from specific camera angle? If you'd try to rotate the camera, would those artifacts shift to other location or would they remain at the same position?
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2019-11-07, 16:10:40
Reply #4

Frood

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Is this railclone by chance? / Can you show a wire or screenshot with active edges of the object(s)?


Good Luck


Never underestimate the power of a well placed level one spell.

2019-11-07, 17:33:58
Reply #5

dj_buckley

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Nope not railclone.  This is the geometry - simple extruded spline.

2019-11-07, 17:47:53
Reply #6

dj_buckley

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Could it be that they are only visible from specific camera angle? If you'd try to rotate the camera, would those artifacts shift to other location or would they remain at the same position?

Again, if I go more flat on, they are still there, but not as obvious

2019-11-07, 17:53:37
Reply #7

pokoy

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Does it help if you divide the geometry a bit so that you don't have these elongated faces?

The shading/normals look a bit off, too...

2019-11-07, 18:04:18
Reply #8

dj_buckley

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in what way do the shading normals look off

2019-11-07, 18:06:36
Reply #9

Frood

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Yes, I would also try a subdivide 1m or 0.5m mod on top. When 2.5d came to dailies I had a lot strange issues like that but no time to test/investigate in detail. And I was wondering about the lack of displacement tests with straight maps like checker on a cube for instance. Btw: I cannot see any shading in the wood of edges 8]


Good Luck



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2019-11-07, 18:10:12
Reply #10

dj_buckley

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Btw: I cannot see any shading in the wood of edges 8]


Good Luck

Haha gotta get those curves smooth

2019-11-07, 18:16:37
Reply #11

Frood

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Nah, I just admired pokoy's x-ray vision he uses obviously :)


Good Luck



Never underestimate the power of a well placed level one spell.

2019-11-07, 18:27:47
Reply #12

Juraj

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No I can see it too, could be AA issue (3dsMax by default doesn't do much of it) but also the spline.

Is it smooth in viewport when 'edges' are off ?
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2019-11-07, 19:27:15
Reply #13

Frood

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Über-vision everyone here it seems :) Me cannot judge smoothing groups at all from that screenshot, the fate of mortals.


Good Luck



Never underestimate the power of a well placed level one spell.

2019-11-07, 19:30:25
Reply #14

romullus

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Don't be sad, you're certainly not alone at this :]
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2019-11-07, 20:10:42
Reply #15

pokoy

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It's a secret in-house version of the mighty enhance feature you see on TV :D
nah I meant the shading of displaced geometry, it looks a bit darker on the rounded section than I'd expect...

2019-11-07, 20:37:47
Reply #16

dj_buckley

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I'm not sure it's darker, but the displacement is definitely more pronounced, possibly due to the curve itself and the angle of the light hitting it.  I also don't have the best graphics card in this machine it's an old school K620.  However it looks smooth in viewport (i'd like to think I'd recognise a smoothing issue if I saw one.  There's also a map set to screen in a composite node to make lighter patches across the facade and it could just be unfortunate placement of that map too.  But for the curious I've attached without visible edges

See the other attachment too - doesn't seem to happen in areas of shadow just when hit by direct light?

2019-11-07, 21:06:15
Reply #17

romullus

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I would definitely try what others suggested, Corona can be quite picky on those very thin polygons. In fact, i think that removing every other edge from the round corner and then doing that couple more times, would likely solve the issue. For displacement you don't want to have polygons that vary greatly in size and shape.
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2019-11-07, 21:11:15
Reply #18

dj_buckley

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I think the answer is more geometry as suggested.  Here I've added 25 horizontal connects to a section, the bit at the top before it meets the white brick and the artifcats are significantly reduced, compared to the section below and white brick above.  For some reason though I was under the impression Corona's displacement didn't really on geometry subdivision.  For what it's worth, I'm not using autobump either - should I be?

Just to add to this, does anyone know why textures lack detail in Corona - i find this a lot.  The brick for example, the crops I'm sending are from a 6k render.  The texture I'm using is 8k.

Attached a 1:1 crop of the texture, but I can never seem to get that detail through in Corona.  In this instance the texture is applied via a Corona Bitmap node with filtering set to 0.01 and bicubic smoother

2019-11-08, 00:27:31
Reply #19

dj_buckley

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Ok so displacement issues now solved.  Simplified the curves as suggested by removing every other edge (twice), then added horizontal connects.  Artifacts are gone.  So just the texture quality question remaining.  I've switched back to bilinear rather than bicubic as the texture is high res and it's slightly better, but always still feels blurred.  Have also tried disabling filtering for all textures and didn't make much difference

2019-11-08, 01:05:46
Reply #20

dj_buckley

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Spoke to soon ... so now I've added the horizontal connects, it's really obvious which sections of geometry are subdivided and which arent.  See new attachment.  The problem being, adding the horizontal connects has just shifted the problem to the larger flat planes that now have tonnes of horizontal connects.

The only way I can see of getting the displacement to be consistent all over the model is to have perfectly sized even quads everywhere, which simply, isn't practical.  Basically the more subdivision, the better the displacement (or more pronounced/accurate).  But it seems like such a waste of polycount?

So i guess the question is what's the best approach to get consisten displacement across an entire model, making the mesh ultra dense seems silly where it's not needed but if thats the case then the density is going to be controlled by the curved areas and the number of segments needed to keep them looking curved.

I also can't tell which displacement is meant to be correct now either.  Is it the subdivided section or the flat non-divided areas - as they clearly look different in terms of displacement depth/strength.

Finally this new issue shown in the screenshots is not half as obvious with the old displacement - as you can see in the attachment, the old displacement looks much better and the issue is nowhere near as obvious.
« Last Edit: 2019-11-08, 01:19:32 by dj_buckley »

2019-11-08, 08:21:16
Reply #21

Frood

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What you have here are exactly those issues I had when I tested a very early version of the new displacement. Had no time to inspect more (and still don't have), also my lack of knowledge about the technical background of 2.5d made me think it's me doing something wrong. Got all kinds of strange shading issues, irregular displacement heights and geometry which worked somewhat ok with the old displacement showed strong artifacts along edges. So thanks for taking your time for those test.


Good Luck



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2019-11-08, 09:34:31
Reply #22

dj_buckley

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Thanks for confirming.  Now be a good time for one of the Devs to jump in and explain what's happening.  The bit that concerns me the most is this sentence from the release notes.

"Unless we hear of any experiences that contradict this, we plan at some point in the future to remove the old displacement from Corona Renderer and leave only the 2.5D displacement"

It seems it needs much more testing before it's removed completely.  It looked so promising in the release note examples, but now I look again, example A is a fully curved irregular organic surface and example B is a perfectly flat wall.  Mine situation blends the two, flat into curves and it makes the difference between the two very apparent.

I also don't really have time to test this.  This is a live job so for time time being 2.5D is unusable for me.  I'm not sure if autobump would make any difference but it's currently off.
« Last Edit: 2019-11-08, 09:45:25 by dj_buckley »

2019-11-08, 10:14:31
Reply #23

GeorgeK

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As far as personal experience goes this seems to me as a subdivision issue with the geometry. Displacement is always displayed more correctly on curves when polygonal density is somewhat uniform.  Regarding displacement details in 2.5, be sure to lower the screen size(px) below 2.0. Will investigate further the differences between 2.5D and Old-Disp on Curved surfaces and with different maps and get back to you. Thanks for the feedback.
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2019-11-08, 10:30:59
Reply #24

dj_buckley

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In my tests I've been using old displacement on 2 and 2.5 displacement on 1.

I'm happy to share this model with you and include the displacement texture

2019-11-08, 10:39:12
Reply #25

dj_buckley

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As far as personal experience goes this seems to me as a subdivision issue with the geometry. Displacement is always displayed more correctly on curves when polygonal density is somewhat uniform.  Regarding displacement details in 2.5, be sure to lower the screen size(px) below 2.0. Will investigate further the differences between 2.5D and Old-Disp on Curved surfaces and with different maps and get back to you. Thanks for the feedback.

Also I'm not sure this is limited to curves - it seems it just works better on subdvided geometry in general - see attached - the bands of brick running under/above the windows have subdivision, the flat areas between the windows are just one poly.  Both surfaces are flat however.  You can clearly see the displacement on the bands of brick is different.  The bands are only subdivided because I've been forced to due to the curved area out of shot - see screenshot a few posts earler that shows wires.  This is with the old displacement - currently rendering the same shot with the new displacement for comparison.

The old displacement is passable although not ideal as the flat undivided areas still look kinda flat and not really displaced.

2019-11-08, 10:42:44
Reply #26

Frood

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Just posted my initial test scene if someone want's to play around with it:

https://forum.corona-renderer.com/index.php?topic=26398.msg158907#msg158907

Maybe it's useful and someone has some time. I was for example not able to get rid of those regular artifacts along displaced edges, even with pixel size 1.


Good Luck


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2019-11-08, 10:48:39
Reply #27

GeorgeK

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In my tests I've been using old displacement on 2 and 2.5 displacement on 1.

I'm happy to share this model with you and include the displacement texture

I am sure it would help further assess the issue, please refer to the following link: https://corona-renderer.com/upload

As far as personal experience goes this seems to me as a subdivision issue with the geometry. Displacement is always displayed more correctly on curves when polygonal density is somewhat uniform.  Regarding displacement details in 2.5, be sure to lower the screen size(px) below 2.0. Will investigate further the differences between 2.5D and Old-Disp on Curved surfaces and with different maps and get back to you. Thanks for the feedback.

Also I'm not sure this is limited to curves - it seems it just works better on subdvided geometry in general - see attached - the bands of brick running under/above the windows have subdivision, the flat areas between the windows are just one poly.  Both surfaces are flat however.  You can clearly see the displacement on the bands of brick is different.  The bands are only subdivided because I've been forced to due to the curved area out of shot - see screenshot a few posts earler that shows wires.  This is with the old displacement - currently rendering the same shot with the new displacement for comparison.

The old displacement is passable although not ideal as the flat undivided areas still look kinda flat and not really displaced.

Thanks for extra input, will check this too.

Just posted my initial test scene if someone want's to play around with it:

https://forum.corona-renderer.com/index.php?topic=26398.msg158907#msg158907

Maybe it's useful and someone has some time. I was for example not able to get rid of those regular artifacts along displaced edges, even with pixel size 1.


Good Luck




Thanks Frood
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2019-11-08, 10:59:22
Reply #28

dj_buckley

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Will upload the scene shortly - but for what it's worth here's the direct comparison.  Remember the horizontal edges along the bands are only there because the curves needed them.  The more I test this, the more the flat undivided areas barely look displaced, leaving me wondering should we have been dividing the geo all along even before 2.5D - anyway see attachments.

2019-11-08, 11:05:21
Reply #29

dj_buckley

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so it would appear the flat undivided areas look fine and consistent between both version of displacement.  BUT ... the curve needs subdivision - which evidently screws up the displacement and makes it inconsistent with the flat areas - sooooo I'm lost :)

2019-11-08, 11:07:46
Reply #30

dj_buckley

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Scene has now been uploaded 1573207621_CER003-BLOCK-A-B-MASTER-06.max

There are no textures, but it's just a brick texture so you can test with any random brick you have.  I've only uploaded the curved building too, the test renders have been coming from a master scene which this building is XRef'd into.  So you've got the X-ref.  There should be a layer (currently turned off) in there called _TESTING which will have a ground plane/daylight etc.

2019-11-08, 11:09:12
Reply #31

GeorgeK

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Will upload the scene shortly - but for what it's worth here's the direct comparison.  Remember the horizontal edges along the bands are only there because the curves needed them.  The more I test this, the more the flat undivided areas barely look displaced, leaving me wondering should we have been dividing the geo all along even before 2.5D - anyway see attachments.

Would need to investigate your scene on this, because I've tested many flat surfaces with no issue what so ever on 2.5D and old.  I've also destroyed the flat geometry with tons of edges, floating vertices, inverted normals, x-form manipulation, different texture displacements, everything worked the same.

Something is really going on there, make sure they use the same displaced material and that the UV'S are correctly set.
“Every artist was first an amateur”

2019-11-08, 11:09:57
Reply #32

dj_buckley

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Will upload the scene shortly - but for what it's worth here's the direct comparison.  Remember the horizontal edges along the bands are only there because the curves needed them.  The more I test this, the more the flat undivided areas barely look displaced, leaving me wondering should we have been dividing the geo all along even before 2.5D - anyway see attachments.

Would need to investigate your scene on this, because I've tested many flat surfaces with no issue what so ever on 2.5D and old.  I've also destroyed the flat geometry with tons of edges, floating vertices, inverted normals, x-form manipulation, different texture displacements, everything worked the same.

Something is really going on there, make sure they use the same displaced material and that the UV'S are correctly set.

It's all the same material - basic box mapping - anyway the scene has been uploaded, please test away.
« Last Edit: 2019-11-08, 11:15:14 by dj_buckley »

2019-11-08, 12:53:03
Reply #33

GeorgeK

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Will upload the scene shortly - but for what it's worth here's the direct comparison.  Remember the horizontal edges along the bands are only there because the curves needed them.  The more I test this, the more the flat undivided areas barely look displaced, leaving me wondering should we have been dividing the geo all along even before 2.5D - anyway see attachments.

Would need to investigate your scene on this, because I've tested many flat surfaces with no issue what so ever on 2.5D and old.  I've also destroyed the flat geometry with tons of edges, floating vertices, inverted normals, x-form manipulation, different texture displacements, everything worked the same.

Something is really going on there, make sure they use the same displaced material and that the UV'S are correctly set.

It's all the same material - basic box mapping - anyway the scene has been uploaded, please test away.

Hey dj_buckley,

Your displacement map ID channel is 1 on multi/sub material slot 2, and your UVWmodifier channel is 3. While bump and 2/3 of diffuse textures are set on 1 resulting on things being shown and not shown upon rendering. I would suggest you collapse the entire thing to a clear-issue free editable poly, and apply a single UV modifier. Also the object/polygon ID's of the horizontal building support beams is 1 on hidden geometry and 3 on shown.

For the horizontal support-beams you don't need any tessellation to your geometry for displacement to be shown correctly, on flat surfaces. Preferably keep the face polygon to a simple quad but do address the curvature with density. If you decide to go with density then preferably go for isometric, uniform edge tessellation.

We further investigate this issue with flat surfaces and density and compare between 2.5D and old. Cheers
“Every artist was first an amateur”

2019-11-08, 13:01:26
Reply #34

dj_buckley

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Your displacement map ID channel is 1 on multi/sub material slot 2, and your UVWmodifier channel is 3. While bump and 2/3 of diffuse textures are set on 1 resulting on things being shown and not shown upon rendering. I would suggest you collapse the entire thing to a clear-issue free editable poly, and apply a single UV modifier. Also the object/polygon ID's of the horizontal building support beams is 1 on hidden geometry and 3 on shown.

This doesn't seem unusual to me - the multi sub has 2 materials for 2 different bricks.

Multi-sub 1 - brown brick - all maps relating to brown brick are set to Channel 1 - there is a corresponding UVW Box Map set to channel 1 to control this.
Multi-sub 2 - white brick - all maps relating to white brick are set to Channel 2 - there is a corresponding UVW Box Map set to channel 2 to control this.

The brown brick has an extra map in it's diffuse slot (part of a composite node) to overlay across the entire building - this is set to Channel 3 - there is a corresponding UVW Box Map set to channel 3 to control this?

So I don't see the issue.  Brown brick/white brick and the overlay texture are all different real world scales.

The support beams themselves don't have the multi-sub applied - juse the brown brick material.  This same brown brick material is Instanced into the multi-sub for the parts of the facade where the brick changes from brown to white.

Surely this is perfectly normal or are you saying I can't use a multi-sub, multi channel setup to get displacement to work properly?


With regards the support beams not needing the tesselation, I no they don't.  However, they were created when adding the connected for the curve.  The issue is that without the tesselation, the displacement looks vastly different when it reaches the curve as you go from non tesselated geo to highly tesselated geo for the curve.
« Last Edit: 2019-11-08, 13:04:59 by dj_buckley »

2019-11-08, 15:40:42
Reply #35

GeorgeK

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Your displacement map ID channel is 1 on multi/sub material slot 2, and your UVWmodifier channel is 3. While bump and 2/3 of diffuse textures are set on 1 resulting on things being shown and not shown upon rendering. I would suggest you collapse the entire thing to a clear-issue free editable poly, and apply a single UV modifier. Also the object/polygon ID's of the horizontal building support beams is 1 on hidden geometry and 3 on shown.

This doesn't seem unusual to me - the multi sub has 2 materials for 2 different bricks.

Multi-sub 1 - brown brick - all maps relating to brown brick are set to Channel 1 - there is a corresponding UVW Box Map set to channel 1 to control this.
Multi-sub 2 - white brick - all maps relating to white brick are set to Channel 2 - there is a corresponding UVW Box Map set to channel 2 to control this.

The brown brick has an extra map in it's diffuse slot (part of a composite node) to overlay across the entire building - this is set to Channel 3 - there is a corresponding UVW Box Map set to channel 3 to control this?

So I don't see the issue.  Brown brick/white brick and the overlay texture are all different real world scales.

The support beams themselves don't have the multi-sub applied - juse the brown brick material.  This same brown brick material is Instanced into the multi-sub for the parts of the facade where the brick changes from brown to white.

Surely this is perfectly normal or are you saying I can't use a multi-sub, multi channel setup to get displacement to work properly?


With regards the support beams not needing the tesselation, I no they don't.  However, they were created when adding the connected for the curve.  The issue is that without the tesselation, the displacement looks vastly different when it reaches the curve as you go from non tesselated geo to highly tesselated geo for the curve.

Hi again, it was merely a suggestion knowing how 3ds max can really bug out hierarchies that supposed to work hehe:). So I am still testing many things with the issue at hand, your scene seems indeed to have issues with certain flat geometries and the new displacement, although even with the old one the flat surfaces don't behave correctly either, just the effect seems to be more subtle.

I am providing a comparison of a 4k texture with displacement between 2.5D and the Old, the plane does have 12 length segments. In all the scenes I've tested with various lighting scenarios (check screenshots) and different geometries, the curvature seems to be the most prominent one. One thing I've noticed is that on your scene Customize-Units set up Displayed Unit-scale you are on Metric with millimeters, yet on the unit-setup it's on Centimeters, what I would like to know is if this was changed at any time within the time you working on the scene. For some reason testing of certain flat surfaces with small horizontal subdivision does produce strange results, something I was unable to reproduce in other scenes for now except the one you've provided. So further investigation is needed.

Again thanks for the input!
« Last Edit: 2019-11-08, 15:45:44 by Corona_GK »
“Every artist was first an amateur”

2019-11-08, 15:42:31
Reply #36

dj_buckley

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Thanks.  The scene units have never changed.  I've built it all from scratch

2019-11-08, 15:47:49
Reply #37

dj_buckley

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Your displacement map ID channel is 1 on multi/sub material slot 2, and your UVWmodifier channel is 3. While bump and 2/3 of diffuse textures are set on 1 resulting on things being shown and not shown upon rendering. I would suggest you collapse the entire thing to a clear-issue free editable poly, and apply a single UV modifier. Also the object/polygon ID's of the horizontal building support beams is 1 on hidden geometry and 3 on shown.

This doesn't seem unusual to me - the multi sub has 2 materials for 2 different bricks.

Multi-sub 1 - brown brick - all maps relating to brown brick are set to Channel 1 - there is a corresponding UVW Box Map set to channel 1 to control this.
Multi-sub 2 - white brick - all maps relating to white brick are set to Channel 2 - there is a corresponding UVW Box Map set to channel 2 to control this.

The brown brick has an extra map in it's diffuse slot (part of a composite node) to overlay across the entire building - this is set to Channel 3 - there is a corresponding UVW Box Map set to channel 3 to control this?

So I don't see the issue.  Brown brick/white brick and the overlay texture are all different real world scales.

The support beams themselves don't have the multi-sub applied - juse the brown brick material.  This same brown brick material is Instanced into the multi-sub for the parts of the facade where the brick changes from brown to white.

Surely this is perfectly normal or are you saying I can't use a multi-sub, multi channel setup to get displacement to work properly?


With regards the support beams not needing the tesselation, I no they don't.  However, they were created when adding the connected for the curve.  The issue is that without the tesselation, the displacement looks vastly different when it reaches the curve as you go from non tesselated geo to highly tesselated geo for the curve.

Hi again, it was merely a suggestion knowing how 3ds max can really bug out hierarchies that supposed to work hehe:). So I am still testing many things with the issue at hand, your scene seems indeed to have issues with certain flat geometries and the new displacement, although even with the old one the flat surfaces don't behave correctly either, just the effect seems to be more subtle.

I am providing a comparison of a 4k texture with displacement between 2.5D and the Old, the plane does have 12 length segments. In all the scenes I've tested with various lighting scenarios (check screenshots) and different geometries, the curvature seems to be the most prominent one. One thing I've noticed is that on your scene Customize-Units set up Displayed Unit-scale you are on Metric with millimeters, yet on the unit-setup it's on Centimeters, what I would like to know is if this was changed at any time within the time you working on the scene. For some reason testing of certain flat surfaces with small horizontal subdivision does produce strange results, something I was unable to reproduce in other scenes for now except the one you've provided. So further investigation is needed.

Again thanks for the input!

When you say my scene has issues with the flat geometry using both 2.5D and Old displacement, I assume you mean the flat geometry that has the horizontal edges?  The flat geometry that is just a single poly is working as expected?

2019-11-08, 16:26:04
Reply #38

steyin

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Not sure if this helps or is in the same vein as the issue at hand, but I normally model in AutoCAD and import into Max. For brick buildings most of the time the modeling is made up of extrusions that intersect (say a pier and horizontal sill) but in the end have the same texture applied. I import as a linked file with geometry grouped to layers.

Displacement never handled this intersecting geometry well so I would add a smooth modifier and then a tessellate modifier operating on polygons, edge and tension set to .001 as turbosmoothing anything from CAD never seems to work. This workflow seems to work pretty well for displacement overall and for eliminating issues at those intersections.

I've also tried using subdivide, meshsmooth and quadifry all, but they never work as well.

2019-11-08, 17:51:11
Reply #39

maru

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Reported.
(Internal ID=420575272)

Also another:
(Internal ID=421793979)

2019-11-08, 18:11:49
Reply #40

dj_buckley

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Not sure if this helps or is in the same vein as the issue at hand, but I normally model in AutoCAD and import into Max. For brick buildings most of the time the modeling is made up of extrusions that intersect (say a pier and horizontal sill) but in the end have the same texture applied. I import as a linked file with geometry grouped to layers.

Displacement never handled this intersecting geometry well so I would add a smooth modifier and then a tessellate modifier operating on polygons, edge and tension set to .001 as turbosmoothing anything from CAD never seems to work. This workflow seems to work pretty well for displacement overall and for eliminating issues at those intersections.

I've also tried using subdivide, meshsmooth and quadifry all, but they never work as well.

The model is completely built inside 3DS Max, so no issues there, i'd also go as far as saying it's the cleanest model I've ever built haha

2019-11-09, 23:06:41
Reply #41

lupaz

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It seems I'm having a similar problem. see attached please.

It's just a box with a chamfer modifier. Smooth: "smoothing chamfer only"

2019-11-09, 23:11:27
Reply #42

dj_buckley

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Looks that way.  It does make me wonder what was actually tested because these are pretty basic production techniques that I use in every single project.  However the Devs are now looking into it so I'm hopeful for a fix soon.  In the meantime I'm back to old displacement but even that is kinda broke

2019-11-19, 11:37:43
Reply #43

matsu

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I'm adding this to the thread, even though this isn't strictly about curves, but rather about the 2.5D displacement in general.

I just tried setting up a simple textured lawn thing, and noticed some strange artifacts. Tried to see where it was coming from, and I realised it was coming from the 2.5D displacement. Tried changing to 3D and it's a huge difference.
It's just a simple JPG file, loaded with CoronaBitmap at gamma 1.0 and the bitmap size is bigger than the sample plane, so no repetition there. Displacement is at 1px in both cases.

Help/suggestion?

I think I will consider using 2.5D only in cases where memory is an issue, since the look is significantly worse. :(


2019-11-19, 11:39:59
Reply #44

GeorgeK

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I'm adding this to the thread, even though this isn't strictly about curves, but rather about the 2.5D displacement in general.

I just tried setting up a simple textured lawn thing, and noticed some strange artifacts. Tried to see where it was coming from, and I realised it was coming from the 2.5D displacement. Tried changing to 3D and it's a huge difference.
It's just a simple JPG file, loaded with CoronaBitmap at gamma 1.0 and the bitmap size is bigger than the sample plane, so no repetition there. Displacement is at 1px in both cases.

Help/suggestion?

I think I will consider using 2.5D only in cases where memory is an issue, since the look is significantly worse. :(

Hey Matsu, what is the topology of your plane? Is it equally subdivided, can you please provide a wireframe?
“Every artist was first an amateur”

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.
“Every artist was first an amateur”

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.
Vray who?

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.
“Every artist was first an amateur”

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