What data is stored when you create a pose using the Pose Tool?

[tiburbage]

In this video, which is about the 2022 Multi-Resolution Sculpt Object support, I think to demonstrate how mesh data changes propagate through a Multi-Res Level stack, the Pose Tool is used to pose the character's hands. But what I wasn't expecting is that the pose is being stored on a Layers panel layer. What is being stored there? Is it vector displacement data? Or can a Layers panel Layer store more than just pixel data?

This raised broader questions I've never seen fully explained about Layers panel layers and all of the types of data they do and don't contain, and whether the mysterious Layer 0 is just an ordinary Layer or has some "special properties"...

Edited June 14, 2023 by tiburbage

[Oleg Shapov]

1 hour ago, tiburbage said:

and whether the mysterious Layer 0 is just an ordinary Layer

Layer 0 is the auxiliary layer. it is better not to use it.

[Carlosan]

The Layers Panel changes depending on which Room you are working in. A layer is not per object base but is a kind of scene layer.

In the Paint Room, Layers are used much like you would in Photoshop or other painting applications, where aspects of each Layer can be controlled independently, such as blending modes and opacity but with additional control over how Depth painting affects the Layer in question.

In Sculpt room, instead of color information, it has deformation information per layer. So, for example, one layer could be for large sculpting deformations, and then another could be for fine details, etc.

To bake the sculpt-layer deformation, resampling the mesh should achieve that.

Layer 0

– What is layer 0 in 3DCoat?

Think about layers as you think about Photoshop layers. Layer0 is like Background in PS.
About 3DCoat, think opacity as RBGA color alpha value. To get opacity variation (add semi-transparent mat etc.).
You only need to paint with an alpha value. then when you hide layer 0 now, you see semi-transparent or fully transparent with the layer color alpha value. Or you can set layer opacity, e.g., if you set layer one opacity value as 0.3, then hide “layer 0” now you should see 0.3 alpha color of the layer (semi-transparent).

The reason why 3DCoat keeps “layer 0” visible, it makes the user easy to color (overwrite layer 0) mesh. (layer 0 keep alpha as 1.0 (no transparent) and color perfect 0.5 0.5 0.5 RGB).
If there is no layer 0, you may not see any surface until you import the map or actually paint on the surface in another layer. It makes us difficult to paint.

After the painting or adding smart material with alpha value, hide layer 0, then export color (diffuse/albedo) map as RGBA (png, tiff, etc.). Then the exported color map keeps the alpha value.
or you can choose the option to export the “Black and white opacity” map with the RBG color map.

Use an alpha value of color or export as an opacity map (black and white) depending on which render application you may use. However, most of the render engines and shaders can use the alpha of color map correctly.

Layer 0: Avoid using it for any purpose but transparency.
It contains mesh data and a “base coat” of paint for baking.
If you erase the paint, things still bake just fine. However, the transparent areas created will be baked as alpha/trans.
Also, if you hide Layer 0, it bakes fine and entirely with alpha/trans, whereas any other layer doesn’t contain color data.

---

Displacement is always based on Layer 0. But the positions of vertices on exported OBJ file depend on your choice. It is better to use such combinations of export checkboxes:

– set 1:

[x] Use source positions
[ ] Pick positions from Layer0
[ ] Coarse…

Use it if Layer 0 was not distorted.

– set 2:

[ ] Use source positions
[x] Pick positions from Layer0
[x] Coarse…

Use it if Layer 0 was distorted. Pick from layer 0 will save new positions, coarse will prepare it for further subdivision.

But if Layer X were not normally distorted, just displacement export would not help. You need to re-bake the mesh to get normal displacement or use vector displacement.

[tiburbage]

Yeah, per Layer 0 being "an auxiliary layer" which should be left alone, that was my take on it, and I'm planning to never touch it -- just build layers on top of it.

Carlosan, thanks for the long explanation and suggest you might want to add that to the base documentation if it isn't there already.

The thing I was really trying to get clear in my mind was if Layers can store data other than shading data (PBR+Depth+Opacity), what are they? Perhaps pose data, which I think of as Morph (aka Blend Shape) data, is just stored as displacement? Just curious...

But since the topic became about Layer 0, is there anything you can ONLY do via Layer 0, or can one simply leave it alone and build what you need in layers on top of it?

Edited June 16, 2023 by tiburbage

[Carlosan]

yes, simply leave it alone and build what you need in layers on top of it.

Erase the paint area on Layer0 to create transparent areas. It will be baked as alpha/trans.

Also, if you hide Layer 0, it bakes fine and entirely with alpha/trans, whereas any other layer doesn’t contain color data.

[tiburbage]

I'm not sure I understand the purpose of "erasing the paint area on Layer 0 to create transparent areas". Are you talking about transparency in a material sense, like Glass, or something else?

[Carlosan]

exactly 

You might try applying a mask on Layer 0 to reduce the opacity, and then in your actual texture layer apply a reflective material. Usually, Layer 0 holds the overall opacity for the object.