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Tore

Hi poly ZBrush model to lo poly A:M model

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that's a petty good result!

 


There is a specific sort of polygon subdivision called "Doo-Sabin" that will take what you have in #2 and convert it to a proper topolology for A:M splines. Is that an option in ZBrush?

 

 

 

 

 

Notice how the dead-end splines in the left example are converted to five- and three-pointer topologies

 

750px-DooSabin_subdivision.png

 

 

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I guess there is also a feature of Zbrush that will create a displacement map that is the difference between the hi-res and lo-res version of the mesh and yo can put it on the lo-res mesh?

 

If there were a way to get that into A:M...

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If ZBrush were less expensive I'd get it and experiment with that, but it's a bit over the top. :(

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3DCoat is very similar to ZBrush, has a less weird interface, has a superior modeler (Voxel sculpting) and cost only 99$ for a "amateur license".

 

Is 3DCoat able to generate the displacement map?

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Just tried it again with 3dCoat 4.8 and it is really working quite nicely for me even importing stuff created not in A:M to A:M in the model window using OBJ for transfering with UV and even alpha-maps...

Here is an example of one of the example objects (OBJs) provided by 3dCoat.

It does not go well with smoothed splines, but by doing it peaked, it is quite well done.

 

Problem is, that it needs to be done very nicely, but it seems to work reasonable well when peaked.

 

Best regards

*Fuchur*

3dcoat.jpg

am_peaked.jpg

am_smooth.jpg

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. Quite impressive, beeing a one man project!

 

Does it have plugins to support import-export with different modelers?

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Just tried it again with 3dCoat 4.8 and it is really working quite nicely for me even importing stuff created not in A:M to A:M in the model window using OBJ for transfering with UV and even alpha-maps...

Here is an example of one of the example objects (OBJs) provided by 3dCoat.

It does not go well with smoothed splines, but by doing it peaked, it is quite well done.

 

Problem is, that it needs to be done very nicely, but it seems to work reasonable well when peaked.

 

Best regards

*Fuchur*

 

Exactly. The translation between subdiv curvature and A:M spline curvature is where it goes horribly wrong. All maps gets distorted as it is all about A:M's different curvature interpretation.

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Does he speak English? Can he be hired to make an A:M plugin? I'm sure the curvature problem has solutions.

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. Quite impressive, beeing a one man project!

 

Does it have plugins to support import-export with different modelers?

 

 

attachicon.gifcoatexport.png

 

 

Those are formats, but not necessarily plugins. Can someone with an SDK add a new format or does the company have to modify the code?

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There already is a plugin for A:M and 3dCoat. It is not flawless unfortunatly, but it is available. The guy who developed it is "Styler" (thanks a lot! Really great stuff :).) on this forum... you could call it one of the forgotten treasures:

 

Here is the link to the topic about the plugin "hato3dc" (Hash Animation:Master to 3dcoat) for transfering data from A:M23dcoat and back:

https://www.hash.com/forums/index.php?showtopic=46804&hl=hato3dc

 

This is extremly close to being perfect... for instance you can export your model, bring it back to A:M and let 3dcoat do the unwrapping for you and stuff like that.

At least with easy things it works quite well... there is this tiny little thing that would have needed to be sorted out and it would be close to perfect.

 

And the plugin still works reasonable well, as you can see below in the image. I just used the newest version of v19, created a object with the lath-tool, brought it to 3d coat using the plugin and exported it back out (seems like A:M does not reimport it using the App-Link anymore... not sure if this is because of 3dcoat or of A:M) as an obj and imported it back into a A:M model.

 

The UVs are intact as far as I can see, but I am not totally sure about distortions.

 

In image 2 you see the problem I am talking about. If this got fixed, it should be quite easy to use A:M and 3dCoat together... :)

 

/////////////////////////////////////////////////////////////////////////////////////////////////

 

Ludo did a lot of things with A:M and 3dCoat already:

- https://www.hash.com/forums/index.php?showtopic=47878&hl=coat

- https://www.hash.com/forums/index.php?showtopic=47911&hl=coat

 

I did a few things myself too:

- https://www.hash.com/forums/index.php?showtopic=46932&page=2&hl=coat&do=findComment&comment=404998

- https://www.hash.com/forums/index.php?showtopic=45468&hl=3dcoat

 

Best regards

*Fuchur*

ha23dc.jpg

ha23dc_2.jpg

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There already is a plugin for A:M and 3dCoat. It is not flawless unfortunatly, but it is available. The guy who developed it is "Styler" on this forum... you could call it one of the forgotten treasures:

 

Is the basic problem that 3D Coat sees A:M splines as straight line segments?

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In this case yes... you would need to increase the subdivision-level quite a lot and then it works reasonable well, but that is not really what you want of cause for A:M...

The thing is: It is very likely the only option to do it like that, because otherwise the UVs would no longer match the object in A:M (it would work for drawing on a already flattend / UVed model in A:M, but it would not be useable to do a automated UV-setup in 3dcoat and bring it back)

 

But the problem I am talking about is the last segment in a spline ring. It is peaked / not really connected there... (you can see it at the second image on the A:M side)

 

I wonder if we can ask Styler for the source code of the plugin or if he could have a look at that... it really would be a great thing.

 

Best regards

*Fuchur*

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Basically, what we want is to paint on a hi-poly model that retains the shape of A:M splines and then get that painting back onto the low-spline A:M model, right?

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Does 3DCoat paint on decals that you have applied in A:M or does it need to make its own decals?

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Tell me if this would be useful...

 

-You make a model in A:M with normal spline density and decal it.

 

-You export a higher density OBJ to ZBrush or 3DCoat

 

-You paint and model in ZBrush/3DCoat... they go crazy and make a zillion new polygons.

-you bring that new hi-density monster as a prop into A:M.

 

-You place your original model and the prop to overlap in the same space.

 

-For every pixel on the original decal in the original model, A:M shoots out a surface normal and measures the distance between the original model and the prop and bakes that as a gray value onto the decal.

 

-The decal is used as a displacement map to give the original model the new shape of the edited prop.

 

-Throw the prop away.

-Your A:M model now looks like the complex polygon model but still has good ol' easy-to-rig A:M splines!

 

 


 

 

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Both is possible... the second option does work already very well. I have used it for instance for the mascot contest entry (Cameleon).

The first is very likely not possible or at least needs a quite complex algorithm to work, since somehow 3d coat would need to "attach" the additional uv-polygones to the one uv-spline it belongs to in A:M.

(it needs to now, which newly created polygones are only representations of the original one)

 

Best regards

*Fuchur*

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That would be excellent if you ask me. It would not work for voxels, but for most kinds of micromodelling it would work great :).

Sounds like a great idea and workflow to me :).

 

Best regards

*Fuchur*

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That would be excellent if you ask me. It would not work for voxels,

 

 

I don't really know "voxels". What about them wouldn't work?

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If all you need to do is paint that would get you across.

The problem I see with that is that, even if you can convert from catmull-clarke back to A:M that still about a 1 to 1 "spline" count and the end result of Zbrush modeling session is going to be a lot of Catmull-Clarkes.

My goal is to find a way to use the ZBrush/3DCoat tools and get the result back into A:M on A:M splines.

 

Here's why I think my scheme is doable now.

 

-A:M can already export Hi-quality OBJs of its spline models and import dense OBJs as props.
-A:M can already put a model and a prop in the same space and be aware of each other (or retopology wouldn't work)

-A:M must be able figure out where each pixel on a bitmap sits on a model (or it wouldn't be able to paint the pixel on the model)
-A:M is able to shoot a normal from any surface point (because that is part of rendering)

-A:M is able to write to decals (because that is what Bake Surface is)

 

Am I missing some important link?

 

What is this missing for people who want to animate in A:M?

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Can you show how the displacement is not working?

In general a displacementmap should be the same everywhere (at least if you are not counting in little rendering differences)

I am not sure which subdivision algorithm is used while rendering but do we really see a difference?

 

The only difference I could see is the difference of the power of the displacementmap. Other than that it already is a subpixel displacementmap in A:M that should do quite the same.

 

Maybe a simple box mapped with the same displacementmap in A:M and Blender for instance should show what you are refering to?

Best regards

*Fuchur*

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Tore, can you post the whole displacement map?

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If you export an UV-mapped model from A:M (needs to be mapped in A:M) use a high subdivisionlevel (something at least as high as 16 polyes per patch or better 64, even higher is most often not necessary).

In 3d Coat you can now paint on the model (paint, not microsmodelling or anything like that) and the distortion should at least be very small (depending on the polygones per patch count and I find 64 to be close to unnoticeable).

Now save the texturemaps and go back to A:M. Sometimes you need to reload the texturemaps, but in general if you render with the green button now, it should already work.

 

This workflow seems to be working fine for me with 3dcoat (do not own ZBrush), since you are not trying to export UV sets or geometry but only change the texturemaps.

 

Best regards

*Fuchur*

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The initial problem I see is that the map is using only a small portion of the available range. The difference between top and bottom of some detail may only be a few steps so the edges of fine details will get a pixelated effect to them.

 

 

ToreLevels.PNG

Obviously Blender deals with that better than A:M, but that's the immediate problem.

 

I will look at this further...

 

 

 

 

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Just generically... 15 steps between high and low is smoother than 3.

The "twisted" look you noted is from pixel jaggies between gray levels.

Blender has a way of dealing with that, but it IS doing something to negate that problem.

I will look at this further.

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Tore, can you send me the model that displacement map goes on? I could experiment with that.

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But that's not the model the displacement map goes to.

 

this one?

post-13038-0-00271200-1522060558_thumb.p

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The really cool thing would be the option to truly translate between A:M and polygon/subdiv world. I feel convinced it could be done by a skillfull programmer, with acces to A:M code.

It would be great if Steffen posted the snippets that contain A:M's patch subdivision heuristics.

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Wouldn't it be easier to add sub d handling of poly models within AM? I could see that being a really powerful addition where you can manipulate the control surface and kick the sub d up at render time.

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It's a neat idea, but subdivs don't give you direct control over the curvature, so your bias handles would go unused in that mode. Instead, there'd need to be support for a crease factor on spline segments.

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You are correct that Sub-d's don't give you direct control over the curvature and are inferior in that aspect to splines BUT splines are more difficult to work with and proprietary to AM which reduces the market. Splines do require much more thinking and planning to work with. Sub-d's are widely popular and would allow many models even stock models to be easily imported and incorporated into scenes beyond the usual rigid props importer.

 

The ability to rig, texture and animate the box (control shape) of an imported model and render the smoothed object at render time would reduce overhead of a typically high poly model and make it manageable within AM.

 

Even though Sub-d's will never have the controls that splines have the popularity of them and wide options of current modelers free and purchased would make me think it would be worth pursuing.

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pixelplucker

Don't get me wrong, I'm all for subdiv rendering in A:M. I'm just pointing out the most obvious implications.

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