Without assumptions of a mesh's direct ownership of its normals,
this was error prone, since normals could potentially be reallocated
when they are tagged dirty or retrieved with write access.
Since normals are derived data, it's always a change to something
else that will cause them to change, like the winding order of a face
or vertex positions. So it's clearer to use tags for those things
directly. It's correct to remove the tag in one place since dirty is
the default state of a new mesh.
When creating the bounding box mesh for the viewport replacement,
copy the material from the original mesh. I'm not sure if Cycles is
meant to load materials from the original mesh or the Alembic file
itself, but either way, this should be a harmless change and fixes the
issue in the report.
Pull Request: https://projects.blender.org/blender/blender/pulls/105798
This simplifies the usage of the API and is preparation for #104478.
The `CustomData_add_layer` and `CustomData_add_layer_named` now have corresponding
`*_with_data` functions that should be used when creating the layer from existing data.
Pull Request: https://projects.blender.org/blender/blender/pulls/105708
Refactoring mesh code, it has become clear that local cleanups and
simplifications are limited by the need to keep a C public API for
mesh functions. This change makes code more obvious and makes further
refactoring much easier.
- Add a new `BKE_mesh.hh` header for a C++ only mesh API
- Introduce a new `blender::bke::mesh` namespace, documented here:
https://wiki.blender.org/wiki/Source/Objects/Mesh#Namespaces
- Move some functions to the new namespace, cleaning up their arguments
- Move code to `Array` and `float3` where necessary to use the new API
- Define existing inline mesh data access functions to the new header
- Keep some C API functions where necessary because of RNA
- Move all C++ files to use the new header, which includes the old one
In the future it may make sense to split up `BKE_mesh.hh` more, but for
now keeping the same name as the existing header keeps things simple.
Pull Request: https://projects.blender.org/blender/blender/pulls/105416
Currently the shade smooth status for mesh faces is stored as part of
`MPoly::flag`. As described in #95967, this moves that information
to a separate boolean attribute. It also flips its status, so the
attribute is now called `sharp_face`, which mirrors the existing
`sharp_edge` attribute. The attribute doesn't need to be allocated
when all faces are smooth. Forward compatibility is kept until
4.0 like the other mesh refactors.
This will reduce memory bandwidth requirements for some operations,
since the array of booleans uses 12 times less memory than `MPoly`.
It also allows faces to be stored more efficiently in the future, since
the flag is now unused. It's also possible to use generic functions to
process the values. For example, finding whether there is a sharp face
is just `sharp_faces.contains(true)`.
The `shade_smooth` attribute is no longer accessible with geometry nodes.
Since there were dedicated accessor nodes for that data, that shouldn't
be a problem. That's difficult to version automatically since the named
attribute nodes could be used in arbitrary combinations.
**Implementation notes:**
- The attribute and array variables in the code use the `sharp_faces`
term, to be consistent with the user-facing "sharp faces" wording,
and to avoid requiring many renames when #101689 is implemented.
- Cycles now accesses smooth face status with the generic attribute,
to avoid overhead.
- Changing the zero-value from "smooth" to "flat" takes some care to
make sure defaults are the same.
- Versioning for the edge mode extrude node is particularly complex.
New nodes are added by versioning to propagate the attribute in its
old inverted state.
- A lot of access is still done through the `CustomData` API rather
than the attribute API because of a few functions. That can be
cleaned up easily in the future.
- In the future we would benefit from a way to store attributes as a
single value for when all faces are sharp.
Pull Request: https://projects.blender.org/blender/blender/pulls/104422
Similar to the previous commit, this simplifies future refactoring
to change the way edges are stored, and further differentiates
single poly variables from array pointers.
With the goal of clearly differentiating between arrays and single
elements, improving consistency across Blender, and using wording
that's easier to read and say, change variable names for Mesh edges
and polygons/faces.
Common renames are the following, with some extra prefixes, etc.
- `mpoly` -> `polys`
- `mpoly`/`mp`/`p` -> `poly`
- `medge` -> `edges`
- `med`/`ed`/`e` -> `edge`
`MLoop` variables aren't affected because they will be replaced
when they're split up into to arrays in #104424.
As part of #95966, move the `ME_SEAM` flag on mesh edges
to a generic boolean attribute, called `.uv_seam`. This is the
last bit of extra information stored in mesh edges. After this
is committed we can switch to a different type for them and
have a 1/3 improvement in memory consumption.
It is also now possible to see that a mesh has no UV seams in
constant time, and like other similar refactors, interacting with
only the UV seams can be done with less memory.
The attribute name starts with a `.` to signify that the attribute,
like face sets, isn't meant to be used in arbitrary procedural
situations (with geometry nodes for example). That gives us more
freedom to change things in the future.
Pull Request #104728
The material indices from the caps were only copied if the base mesh had
a material index attribute. Fix that by copying them manually if the cap
has the attribute.
Consistent with naming from 1af62cb3bf. Keep the "coord"
naming in the "vert_coords_alloc" set of functions since they should be
removed (see #103789).
Caused by 96abaae9ac. Just keep the old argument
in the `_ex` version of the function for now. It can be removed
when the explode modifier is removed in 4.0.
Blender currently has 2 algorithms for merging vertices:
- `BKE_mesh_merge_verts`;
- `blender::geometry::create_merged_mesh`
`BKE_mesh_merge_verts` has a simplified algorithm to work with Array,
Mirror and Screw modifiers. It doesn't support merge results that would
create new faces. However it has shortcuts to be more efficient in
these modifiers.
`blender::geometry::create_merged_mesh` tries to predict all possible
outcomes. So it's a more complex. But it loses in performance to
`BKE_mesh_merge_verts` in some cases.
The performance comparison between these two depends on many factors.
`blender::geometry::create_merged_mesh` works with a context that has
only the affected geometry. Thus a smaller region of the mesh is read
for duplicate checking. Therefore, the smaller the affected geometry,
the more efficient the operation.
By my tests `blender::geometry::create_merged_mesh` beats
`BKE_mesh_merge_verts` when less than 20% of the geometry is affected
in worst case `MESH_MERGE_VERTS_DUMP_IF_EQUAL` or 17% in case of
`MESH_MERGE_VERTS_DUMP_IF_MAPPED` .
For cases where the entire geometry is affected, a 30% loss was noticed,
largely due to the creation of a context that represents the entire mesh.
Co-authored-by: Germano Cavalcante <germano.costa@ig.com.br>
Pull Request #105136
Using spans instead of raw pointers helps to differentiate ararys from
pointers to single elements, gives bounds checking in debug builds, and
conveniently stores the number of elements in the same variable.
Also make variable naming consistent. For example, use `loops` instead
of `mloop`. The plural helps to clarify that the variable is an array.
I didn't change positions because there is a type mismatch between
C and C++ code that is ugly to manage. All remaining code can be
converted to C++, then that change will be simpler.
Pull Request #105138
This code seems to be left over from before edges, polys, and loops were
stored in CustomData. They are already copied by the CustomData copy
calls directly above, which already deal with every other layer.
