Details

Reviewers

Brecht Van Lommel (brecht)
Campbell Barton (campbellbarton)

Commits

rBcfb3011e5214: Sculpt: Mask Extract operator

Summary

This is a new implementation of the mask extract operator, different from the one in the sculpt branch.

It can extract the paint mask creating a boundary loop in the geometry, making it ready for adding a subdivision surface modifier. After experimenting with edit mode operators I found that this combination of boundary vertices and internal vertices smoothing works fine in most cases.

Diff Detail

Repository

rB Blender

Branch

sculpt-mask-extract (branched from master)

Build Status

Buildable 4630
Build 4630: arc lint + arc unit

Event Timeline

Pablo Dobarro (pablodp606) created this revision.Jul 31 2019, 9:44 PM

Harbormaster completed remote builds in B4239: Diff 16744.Jul 31 2019, 9:44 PM

Pablo Dobarro (pablodp606) planned changes to this revision.Jul 31 2019, 9:44 PM

Pablo Dobarro (pablodp606) added reviewers: Brecht Van Lommel (brecht), Campbell Barton (campbellbarton).Jul 31 2019, 9:45 PM

Pablo Dobarro (pablodp606) edited the summary of this revision. (Show Details)

TheRedWaxPolice (TheRedWaxPolice) awarded a token.Jul 31 2019, 9:47 PM

xrg (xrg) awarded a token.Jul 31 2019, 9:49 PM

Erick Tukuniata (erickblender) awarded a token.Jul 31 2019, 10:08 PM

Ted Nielsen (brilliant_ape) awarded a token.Aug 6 2019, 7:20 AM

Is this functionality already in master? 🤔

New implementation of mask extract as a mesh operator

Harbormaster completed remote builds in B4630: Diff 17600.Aug 28 2019, 12:44 AM

Pablo Dobarro (pablodp606) edited the summary of this revision. (Show Details)Aug 28 2019, 12:49 AM

Pablo Dobarro (pablodp606) retitled this revision from Mask extract operator to Sculpt: Mask extract operator.

Eitan Traurig (EitanSomething) awarded a token.Aug 28 2019, 12:54 AM

Marco G (marcog) awarded a token.Aug 28 2019, 11:11 AM

Can't this use the redo panel rather than a modal popup? To me it seems tweaking these settings is better done with interactive feedback.

Adding modifiers feels a little hacky, especially the shrinkwrap one. Shouldn't it just apply them to the mesh immediately rather than keeping them as modifiers?

@Brecht Van Lommel (brecht) Is there a way to apply the shrinkwrap operation after each smooth iteration without using the modifier stack? That would be the ideal solution.
I'm not sure about how the redo panel works, but if it is going to start the whole extraction from scratch, we can't use it in high poly meshes. With the smooth iterations it is already quite slow, so with the modal popup you can disable those features on a high poly mesh. Smoothing and edge border with a high number of polygons does not make much of a difference in the result but the operation time goes from 11 seconds to 1 - 2 seconds.

In D5384#129014, @Pablo Dobarro (pablodp606) wrote:

@Brecht Van Lommel (brecht) Is there a way to apply the shrinkwrap operation after each smooth iteration without using the modifier stack? That would be the ideal solution.

The shrinkwrap modifier calls shrinkwrapModifier_deform(). You can add another function to shrinkwrap.c that you can just add a Mesh and some parameters, and do whatever refactoring is needed to make that work.

Similar for solidify, that's currently a function in MOD_solidify.c, but with some refactoring it can moved to a new function that is used by both the modifier and this sculpt tool.

I'm not sure about how the redo panel works, but if it is going to start the whole extraction from scratch, we can't use it in high poly meshes. With the smooth iterations it is already quite slow, so with the modal popup you can disable those features on a high poly mesh. Smoothing and edge border with a high number of polygons does not make much of a difference in the result but the operation time goes from 11 seconds to 1 - 2 seconds.

It's a bit weak to use a different mechanism for that reason, but I don't think we have a better alternative for now so this is ok.

source/blender/editors/mesh/editmesh_mask_extract.c
255	Capitalize these and other property UI names like a title: `Add Boundary Loop`, `Project to Sculpt`, etc.

This revision now requires changes to proceed.Sep 6 2019, 4:38 PM

Avoid using shirkwrap modifier
Add menu entry
Fix naming

I think we should keep the solidify as a modifier. We can't rely on the redo panel for this operator and it's common to adjust the thickness and creases after extracting.

Harbormaster completed remote builds in B4830: Diff 17954.Sep 8 2019, 12:29 AM

Fix name

Harbormaster completed remote builds in B4831: Diff 17955.Sep 8 2019, 12:30 AM

I think that it would be better to apply the solidify modifier as well, since it's not immediately obvious there is a modifier, when you for example want to join the meshes or sculpt the extracted mesh and get bad results.

Still it can also be useful to tweak the parameters, so I guess the way it is now works too.

source/blender/blenkernel/intern/shrinkwrap.c
1489–1492 ↗	(On Diff #17955)	Ensure `ShrinkwrapModifierData` and `ModifierEvalContext` do not contain uninitialized values. Something like: Depsgraph depsgraph = CTX_data_depsgraph(C); Scene sce = CTX_data_scene(C); ShrinkwrapModifierData ssmd = {0}; ModifierEvalContext ctx = {depsgraph, ob_source, 0};
1499–1511 ↗	(On Diff #17955)	Can use `BKE_mesh_vert_coords_alloc` and `BKE_mesh_vert_coords_apply` for this.

This revision now requires changes to proceed.Sep 9 2019, 7:48 PM

The smoothing doesn't work that great in my tests. Just with the default Sculpting template, paint with the mask brush, the resulting extracted mesh has quite wrinkly boundary. Adding two more subdivision levels or using 20 smooth iterations still leaves it quite wrinkly.

Not necessarily to be solved before commit, but I think it's possible to do better here.