Store paint masks as generic float attributes, with the name
`".sculpt_mask"`. This is similar to 060a534141, which made
the same change for face sets. The benefits are general
consistency, nicer code, and more support in newer areas
that deal with attributes like geometry nodes.
The RNA API is replaced with one created in Python. The new
API only presents a single layer as an attribute class, so it
should be simpler to use in general:
- Before: `object.data.vertex_paint_masks[0].data[0].value`
- After: `object.data.vertex_paint_mask.data[0].value`
Pull Request: https://projects.blender.org/blender/blender/pulls/115119
Design task: #93551
This PR replaces the auto smooth option with a geometry nodes modifier
that sets the sharp edge attribute. This solves a fair number of long-
standing problems related to auto smooth, simplifies the process of
normal computation, and allows Blender to automatically choose between
face, vertex, and face corner normals based on the sharp edge and face
attributes.
Versioning adds a geometry node group to objects with meshes that had
auto-smooth enabled. The modifier can be applied, which also improves
performance.
Auto smooth is now unnecessary to get a combination of sharp and smooth
edges. In general workflows are changed a bit. Separate procedural and
destructive workflows are available. Custom normals can be used
immediately without turning on the removed auto smooth option.
**Procedural**
The node group asset "Smooth by Angle" is the main way to set sharp
normals based on the edge angle. It can be accessed directly in the add
modifier menu. Of course the modifier can be reordered, muted, or
applied like any other, or changed internally like any geometry nodes
modifier.
**Destructive**
Often the sharp edges don't need to be dynamic. This can give better
performance since edge angles don't need to be recalculated. In edit
mode the two operators "Select Sharp Edges" and "Mark Sharp" can be
used. In other modes, the "Shade Smooth by Angle" controls the edge
sharpness directly.
### Breaking API Changes
- `use_auto_smooth` is removed. Face corner normals are now used
automatically if there are mixed smooth vs. not smooth tags. Meshes
now always use custom normals if they exist.
- In Cycles, the lack of the separate auto smooth state makes normals look
triangulated when all faces are shaded smooth.
- `auto_smooth_angle` is removed. Replaced by a modifier (or operator)
controlling the sharp edge attribute. This means the mesh itself
(without an object) doesn't know anything about automatically smoothing
by angle anymore.
- `create_normals_split`, `calc_normals_split`, and `free_normals_split`
are removed, and are replaced by the simpler `Mesh.corner_normals`
collection property. Since it gives access to the normals cache, it
is automatically updated when relevant data changes.
Addons are updated here: https://projects.blender.org/blender/blender-addons/pulls/104609
### Tests
- `geo_node_curves_test_deform_curves_on_surface` has slightly different
results because face corner normals are used instead of interpolated
vertex normals.
- `bf_wavefront_obj_tests` has different export results for one file
which mixed sharp and smooth faces without turning on auto smooth.
- `cycles_mesh_cpu` has one object which is completely flat shaded.
Previously every edge was split before rendering, now it looks triangulated.
Pull Request: https://projects.blender.org/blender/blender/pulls/108014
See #105317
In 46cf093270, face maps were just converted to an integer
attribute. While the internal data remains the same that way, we lose
the names and some convenient methods of interaction. This commit
additionally converts each face map to a separate boolean attribute
using the old name. This does require that no attributes were using that
name already.
Each boolean attribute can be thought of as a selection, accessible in
geometry nodes and properly interpolated by mesh processing
algorithms. The selections no longer have to be unique, meaning
one face can be part of multiple selections.
Pull Request: https://projects.blender.org/blender/blender/pulls/113769