[SOLVED] How to create a curvature map ?

[Gian-Reto]

This is really driving me mad:

 

I just started playing around with DDO. But it seems in order to REALLY use the tool to its full potential, you need a clean curvature map.

 

Now I haven't used curvature maps at all until now, and it seems there is no easy way to create one from 3D Coat.

 

I tried some solutions from the net which convert an AO or Height Texture to a Cavity map, this always resulted in a full white (or almost full white) curvature map in DDO. Just using photoshop to get a red / green map did not help either.

 

Now I know I might need to ask this in the DDO Forum, but as this Forum is now down for more than a day, and has little visitors, and my problem actually starts in 3D Coat because it does not bake this map, I'll try my luck here.

 

Anyone else here that use curvature maps in their pipeline, and how do you create it? If you use xNormal to bake, whats the best way to export a voxel sculpt to xNormals? an Autopo with millions of polies? does that even work? Is there any easy trick I miss besides baking in a different tool than 3D coat? Is there a hidden option in 3D Coat?

 

Seems Voxel Sculpts are not such a good idea anymore compared to polygon sculpts when 3D coat does not provide all necessary tools anymore in the Retopo room.

 

 

Thanks for any help.

 

 

Gian-Reto

[Malo]

Thats true, you cant create curvature maps inside 3d coat.

 

I need curvature maps too, and i use in my pipeline Substance Designer.

Substance Designer creates that curvature for me, based on the normalmap.

Not sure if xNormal could create it from the normalmap.

But you could always work with high and lowpoly that should not be a problem in xNormal.

[AbnRanger]

You have to remember, dDo and Substance have come along and changed/introduced some new features and workflows (in the CG industry) that haven't yet proliferated to other CG apps. For example, 3D Coat was the first commercial app to offer Ptex. Mudbox came along a few years later and supported it. ZBrush still doesn't offer it. This is the first time I've heard of curvature maps...because it is largely a dDo/Substance thing. 3D Coat can create color, spec, normal/displacement, color spec, glow and glow alpha mask maps, and that's about it for the time being. You can bake occlusion in the Paint Room (or when merging from the Retopo room, choosing Per Pixel Paint mode), and export just the AO map by selecting the layer, then go to the TEXTURE menu > Export > Color map.

 

As for creating a curvature map in 3D Coat, you could select the Normal map layer you want to use > click on the Duplicate Layer icon at the bottom of the Layer Panel > with the duplicate layer selected, go to the EDIT menu > SYNC LAYERS w/ EXTERNAL EDITOR (Photoshop) or just hit CTRL + P. From there you might try this technique, if there is not a more streamlined method available:

 

https://www.youtube.com/watch?v=9PCZvdIhOGI

 

[AbnRanger]

Oops....I meant this technique in PS, using the Normal Map:

 

 

You could also try to create a good starting point for a curvature map, using the Cavity painting options in 3D Coat. Maybe start off with MORE in CAVITY and use the previewer to see how it looks as you adjust the cavity level slider. Instead of painting with a Brush, you can use the fill bucket tool or with the Paint Brush selected, uncheck "Ignore Backfaces" in the E-Panel > choose a freeform lasso or rectangle marquee in the E-Panel drag over the whole model and BAM...you have a quick and dirty Cavity map. In the TEXTURES > ADJUST menu you can choose to Smooth (like Guassian Blur) the map some if needed....or make other adjustments to sharpen it, if you like.

 

Then, you could do the reverse to paint the elevations a little by choosing LESS IN CAVITY (maybe with a light grey at one level, adjust the level a bit more and choose white). Once you think it looks good, you can export that layer from the TEXTURES menu. 3D Coat won't spit it out as a Curvature map if you export the whole model, but you can create auxiliary layers to fill with colors you want for dDo and substance and export them separately or export layers to a PSD file.

 

You can quickly fill UV islands, to color them for dDo's purposes, by using the TEXTURE EDITOR and with the FILL tool active > simply click on the UV island. It fills faster than you can do it in PS.

 

Some Cavity Painting done in this video:

 

And the Texture Painting using the Texture Editor (UV island fill trick I mentioned):

https://i1.ytimg.com/vi/RsPELRzPpUc/mqdefault.jpg

https://i1.ytimg.com/vi/RsPELRzPpUc/mqdefault.jpg

[Carlosan]

Object space normals can be used to create curvature maps: images where black pixels represents planar surface points, and white pixels represent points of high curvature on the mesh.

---------------------------------------

0001532: Create a curvature map

http://3d-coat.com/mantis/view.php?id=1532

 

please add a +1

 

--------------------------------

http://wiki.polycount.com/CurvatureMap

 

A map that stores the convexity/concavity of the mesh. Also called Concave, Convexity, Pits & Peaks, Worn Edge.

The colors can be used to mask where the surface would get more wear, where it would accumulate more dirt, where sub-surface scattering might occur, to check for surface continuity, etc.

 

--------------------------------

Convexity tool in Xnormal

you can also generate cavity/curvature map in xnormal

 

[Gian-Reto]

Wow guys.... so many responses in just about 12 hours. I am amazed

 

I have to say, Curvature maps are also new to me, and even though now that I know about them I can see the use of it even without DDO, without my testing drive of DDO I would have never found out about it. I can understand that it might take some time to integrate all that new PBR Stuff into 3D Coat and have no Problems with waiting.

 

I just would like to find some bridging solution so I can start using DDO and, if I will also like it, Substance Designer now, so I can prepare for Unity 5 in which PBR is one of the big new things (I vowed to not jump on the 3rd party PBR Bandwagon in Unity 4 until I have seen what the official shaders look like).

 

I guess I will give Substance Designer a spin first. If it can convert a normal map into a curvature map, great. Else I will try some of the other workarounds described here.

 

@ carlosan: a, I think I misunderstood what a curvature map is. I thought it would be more along the lines of an AO map (convexity is white, concavity is black). No wonder my self made curvature maps did not work!

 

I will certainly give it a +1. Having this ability directly in 3D Coat will integrate Voxel sculpting much more seamless into a PBR pipeline, and as far as I can tell, PBR is here to stay (while most of the DX11 fads like tesselation.... lets say, I seldom felt the urge to create a displacement map )

 

 

Thanks for all you useful Information guys!

 

 

Gian-Reto

 

 

EDIT: Just gave the substance designer a spin. I could bake out a curvature map quickly, and while the map out of the box still does not seem what DDO expects, with some tweaking to the values in the mask designer I was able to get a 95% correct Edge Wear.

There is still the problem with the Edges of the 2D Texture getting incorrect wear, but it is really small now, and maybe I made a mistake while baking the curvature map. I will try again. And might try the manual Photoshop way anyway.

 

Thanks again to everyone that posted!

 

 

EDIT #2:

Forgive my noobishness, I never used mantis before so.... where do I give +1 to an issue/feature?

Edited July 5, 2014 by Gian-Reto

[Malo]

Curvature or Cavitymaps aren´t realy new.

They should be nearly the same age as Ambient Occlusion maps have.

Both find his usage in Game Design a long time now.

 

For Mantis, you have to create a new Account, after that you could post and add requestst.

Edited July 5, 2014 by Malo

[AbnRanger]

Curvature or Cavitymaps aren´t realy new.

They should be nearly the same age as Ambient Occlusion maps have.

Both find his usage in Game Design a long time now.

 

For Mantis, you have to create a new Account, after that you could post and add requestst.

Yeah it's been around so long and so common, there is precious little on youtube that covers it in any detail.

[Malo]

Whats your Problem?

Are you still upset because i am against your wishes to include cycles in 3d coat?

And now you try to bashing around everything that have to do with game design?

 

Zbrush could do that since a long time. In this 6 years old video it gets explained.

Maybe if i have more time i found an older ones. And i am sure that zbrush could do that since 10 years.

 

I know you are not very interestet in game design, maybe you should update your knowledge in that area a little bit.

 

[Carlosan]

its not new,

may be its new how SD and DDo implemented it

 

r7_vertCurvature.py

at polycount is dated 06/2010

 

- February 1, 2007. xNormal v3.10.0 patch add it too:

Added the possibility to output convexity, thickness and proximity maps

 

anyway, any confrontation is a waste of time

 

to add the possibility to output convexity, thickness and proximity maps in 3DC is a goal for everyone... pass away and add a +1 to support it

[Gian-Reto]

guys, guys... does it really matter since when curvature maps are being used? Fact is the whole topic has only a few hard to find vids explaining how to create them, and about 3 different names for more or less the same thing.

Anyway, just to give you a heads up: after some tinkering Surface Designer creates a good curvature map. Found out that I had to feed SD the normal map as 3d Coat outputs it, not the version with inverted green channel I need for both Unity and DDO (Maybe somebody here can explain that to me? Is that the inverted Y channel?).

Now DDO works like a charm.... well, almost. There are still some problems around the seams, I guess there is no way around some manual intervention there. Guess I need to brush up the masks manually after I am happy with the generated one.

Edited July 6, 2014 by Gian-Reto

[AbnRanger]

Whats your Problem?

Are you still upset because i am against your wishes to include cycles in 3d coat?

And now you try to bashing around everything that have to do with game design?

 

Zbrush could do that since a long time. In this 6 years old video it gets explained.

Maybe if i have more time i found an older ones. And i am sure that zbrush could do that since 10 years.

 

I know you are not very interestet in game design, maybe you should update your knowledge in that area a little bit.

That video is regarding a cavity map...not a CURVATURE map. And I mention my support/vote for Cycles, and you decide to start bashing it. Then, I address the OP and you decide to try and correct me...referencing the wrong subject.

[AbnRanger]

.....I know you are not very interestet in game design, maybe you should update your knowledge in that area a little bit.

[GeneralAce55]

That video is regarding a cavity map...not a CURVATURE map. And I mention my support/vote for Cycles, and you decide to start bashing it. Then, I address the OP and you decide to try and correct me...referencing the wrong subject.

Just saying, but a curvature map and a cavity map are the same thing under different names, different programs call them different things

Edit: At least as far as I can tell, because if you put in a cavity map exported from z-brush into the curvature map input in substance designer, it seems to work fine, please feel free to correct me anyone, always open to learning something new!

Edited July 6, 2014 by GeneralAce55

[Carlosan]

cavity map to overlay over specular or diffuse... to glow or dark cavities with fine details, dirt the crevices...

 

ambient occlusion map to dark big zones

 

curvature map to separate convexity occlusion and concavity occlusion

[GeneralAce55]

cavity map to overlay over specular or diffuse... to glow or dark cavities with fine details, dirt the crevices...

ambient occlusion map to dark big zones

curvature map to separate convexity occlusion and concavity occlusion

Thanks Carlosan for the clarification!! Now I finally know what they all do exactly haha

[Malo]

@ABN

Sir, you are funny.

[AbnRanger]

Just saying, but a curvature map and a cavity map are the same thing under different names, different programs call them different things Edit: At least as far as I can tell, because if you put in a cavity map exported from z-brush into the curvature map input in substance designer, it seems to work fine, please feel free to correct me anyone, always open to learning something new!

 

Just saying, but a curvature map and a cavity map are the same thing under different names, different programs call them different things Edit: At least as far as I can tell, because if you put in a cavity map exported from z-brush into the curvature map input in substance designer, it seems to work fine, please feel free to correct me anyone, always open to learning something new!

Well...you know, an AO map and a Cavity map are kissing cousins, but there is some slight difference. When I saw Marmoset's info on it, I thought it was very close to a cavity map, too, but It seems it's a little deeper than that...based on concave convexion angles? I've heard of a lot of different maps before, but this was the first time I've heard of curvature.

 

I'm going to have to try out that Quixel Suite before that Sept. 8 deadline, so I'm kind of curious like the OP, how to generate one dDo can work with, without a lot of fuss.

[Gian-Reto]

So, I had more fun in DDO.... and I can honestly say I have mixed feelings about it now that I tried out with a working curvature map.

 

While the tool will be pretty useful for my purposes (lowpoly game models), as long as I prepare the meshes with DDO in mind, I don't think I would really recommend this tool for high-poly assets for visualizations and movies and so on (I guess thats not the target audience).

 

There are some pretty severe problems with the tool apart from the general buginess (its in beta, so I guess that might sill change) and ugliness (yes its a PS Plugin, so it will never be slick and smooth like a standalone tool). Biggest problem actually stops this tool from being too useful for some types of meshes:

 

All Texture Channels are "fitted" in 2D Texture Space. there is NO 3D Mapping unto the Mesh.

That might be obvious, but it is a pretty nasty limitation. It means that while meshes with all seams in crevices or along the Edges will come out mostly fine, but as soon as there is an UV seam along a flat surface, the seam will be pretty visible, depending on the materials used.

 

With rust for example there are a lot of variations in the diffuse texture, making it pretty hard to hide the seams, if you don't turn the mask down to just a little rust visible.

 

The biggest problem is though with the masks itself. They also suffer from this Problem, therefore as soon as you have a seam along a flat surface, you will have to turn the mask down to just follow the AO or Curvature, which makes bigger edge wear patterns impossible.

 

Of course, depending on the object or style you are after this might not affect you. I only really found this limitation to be a problem with painted metal edge wear and rust.

 

 

Anyway, here is first truly finished Project. I thought it would be a simple project perfect for trying out DDO, but because of the cylindrical nature of the object and the mentioned limitations, seams along the sides were non avoidable, thus I had to work long and hard on the edge wear masks to hide any troubles with the 2D to 3D Projection.

 

I created the curvature mask with Substance Designer, which gave me this curvature mask:

 

 

Its hard to see in the smaller picture, but there is a small amount of noise in the map. I guess this unavoidable, and its beraly noticable, but of course out of the box DDO will pick it up. Doh!

 

I painted the ID Colors in 3D Coat. Quick and easy as its a simple object.

 

I then created a DDO Project with this curvature map, TS normals and ID Map from 3D Coat (normal green channel flipped), Object Space normals created with xNormals, AO also baked out in SD.

 

This gave me an unpainted barrel in 3DO:

 

 

I then added a smart material, which out of the box looked horrible:

 

 

Only good thing about the out of box setting with this material and this curvature map was: the seams were quite well covered by the mask.

 

I then started tweaking masks, added materials, manually added a Textlayer, and because of that had to add some materials later manually in PS as some DDO Functionality stopped working because of this manually placed text layer. Doh^2!

 

 

Finished Oil Barrel. I am quite happy with the result, even though the edge wear is way to even.... but as I would spend hours just to get the right mask parameters that give me less even edge wear without emphasizing the seams, I will leave it like this for now. Especially as it will be a rather small object in my game prototype (yes, for that the texture is maybe overdone anyway. And Resolution and Polycount to high. But I will use it as a test object for a LOD-Generator in Unity, so thats fine)

 

 

I spent 10 minutes on the sculpt (I love the new Lathe Tool!), 1 hour in retopo (yes, I am not too good with it and therefore take much too long there), and about 2-3 hours in the end on texturing (if I don't take all the hours into account I spent on finding out about the curvature map and analysing the many troubles with DDO).

 

Not quite the quick and easy solution the vids promised!

 

Of course, with more hand on expierience and some presets that time will come down considerably, and with a better prepared Mesh some of the problems might not be so problematic. And of course, 3 hours for a model with all this edge wear might not be too bad anyway.

 

Still, there are at least 2 big hurdles I see that stop this tool from being perfect: No 3D Projection of textures, and general buginess. I really hope they fix the later, and I fear it will take a major rework of their PS plugin, if its even possible, to fix the first one.

 

 

Andrew, if you are reading this and ever think about integrating DDO-Like Smart-Material like capabilities: make sure you project the materials in 3D space unto the model, don't go the easy 2D texture Space route. I know its most probably much more work to do.

But the feature would incredibly more valuable to any texture artist this way!

Edited July 8, 2014 by Gian-Reto

[Carlosan]

Object Space normals created with xNormals

 

do you tested the workflow using 3DC world space ?

 

[Gian-Reto]

Object Space normals created with xNormals

 

do you tested the workflow using 3DC world space ?

 

WorldSpace.jpg

 

Ah, no, I missed that. Good point. I will test it tomorrow and update this post.

[Gian-Reto]

No Edit button? Maybe the Edit function is closed after some time?

 

Anyway, tried the World Space Normals exported from 3D Coat in DDO today. They work quite fine even though DDO Expects Object Space normals (they seem to match in my case, could be different for other objects).

 

That said, you do not need to flip the green channel for the WS Normals exported from 3D Coat. Doing this seems to flip the direction of the directional mud material I tried it with. So I guess the flipped Y Axis is only affecting the TS Normals from 3D Coat.

 

Even though the OS / WS Normals are only really needed for directional masking, this is helpful sometimes and exporting direct from 3D Coat cuts one tool out of the pipeline. thanks for the hint carlosan!