Store bevel weights in two new named float attributes:
- `bevel_weight_vert`
- `bevel_weight_edge`
These attributes are naming conventions. Blender doesn't enforce
their data type or domain at all, but some editing features and
modifiers use the hard-coded name. Eventually those tools should
become more generic, but this is a simple change to allow more
flexibility in the meantime.
The largest user-visible changes are that the attributes populate the
attribute list, and are propagated by geometry nodes. The method of
removing this data is now the attribute list as well.
This is a breaking change. Forward compatibility is not preserved, and
the vertex and edge `bevel_weight` properties are removed. Python API
users are expected to use the attribute API to get and set the values.
Fixes#106949
Pull Request: blender/blender#108023
Add the ability to retrieve implicit sharing info directly from the
C++ attribute API, which simplifies memory usage and performance
optimizations making use of it. This commit uses the additions to
the API to avoid copies in a few places:
- The "rest_position" attribute in the mesh modifier stack
- Instance on Points node
- Instances to points node
- Mesh to points node
- Points to vertices node
Many files are affected because in order to include the new information
in the API's returned data, I had to switch a bunch of types from
`VArray` to `AttributeReader`. This generally makes sense anyway, since
it allows retrieving the domain, which wasn't possible before in some
cases. I overloaded the `*` deference operator for some syntactic sugar
to avoid the (very ugly) `.varray` that would be necessary otherwise.
Pull Request: blender/blender#107059
Implements #95966, as the final step of #95965.
This commit changes the storage of mesh edge vertex indices from the
`MEdge` type to the generic `int2` attribute type. This follows the
general design for geometry and the attribute system, where the data
storage type and the usage semantics are separated.
The main benefit of the change is reduced memory usage-- the
requirements of storing mesh edges is reduced by 1/3. For example,
this saves 8MB on a 1 million vertex grid. This also gives performance
benefits to any memory-bound mesh processing algorithm that uses edges.
Another benefit is that all of the edge's vertex indices are
contiguous. In a few cases, it's helpful to process all of them as
`Span<int>` rather than `Span<int2>`. Similarly, the type is more
likely to match a generic format used by a library, or code that
shouldn't know about specific Blender `Mesh` types.
Various Notes:
- The `.edge_verts` name is used to reflect a mapping between domains,
similar to `.corner_verts`, etc. The period means that it the data
shouldn't change arbitrarily by the user or procedural operations.
- `edge[0]` is now used instead of `edge.v1`
- Signed integers are used instead of unsigned to reduce the mixing
of signed-ness, which can be error prone.
- All of the previously used core mesh data types (`MVert`, `MEdge`,
`MLoop`, `MPoly` are now deprecated. Only generic types are used).
- The `vec2i` DNA type is used in the few C files where necessary.
Pull Request: blender/blender#106638
Similar to 7eee378ecc, this change decreases memory usage and
improves performance when copying curves and meshes without changing
their topology. The same change used for custom data layers is applied
to face and curve offset indices, which aren't stored as a custom data
layer.
The implicit sharing info for the offsets is stored in the mesh and
curve runtime structs, since it doesn't need to be written to files
directly. When changing the offsets pointer directly, the sharing info
must be updated accordingly. To make that easier, a few utility
functions take care of common operations like making an array mutable,
resizing an array, and creating sharing info for allocated data.
This commit also clarifies the intention to not allocate the offsets
at all when there are no curves/faces. That slightly complicates some
of the logic, but there's no reason for the single `0` integer to be
allocated.
Pull Request: blender/blender#106907
This integrates the new implicit-sharing system (from fbcddfcd68)
with `CustomData`. Now the potentially long arrays referenced by custom
data layers can be shared between different systems but most importantly
between different geometries. This makes e.g. copying a mesh much cheaper
because none of the attributes has to be copied. Only when an attribute
is modified does it have to be copied.
Also see the original design task: #95845.
This reduces memory and improves performance by avoiding unnecessary
data copies. For example, the used memory after loading a highly
subdivided mesh is reduced from 2.4GB to 1.79GB. This is about 25%
less which is the expected amount because in `main` there are 4 copies
of the data:
1. The original data which is allocated when the file is loaded.
2. The copy for the depsgraph allocated during depsgraph evaluation.
3. The copy for the undo system allocated when the first undo step is
created right after loading the file.
4. GPU buffers allocated for drawing.
This patch only gets rid of copy number 2 for the depsgraph. In theory
the other copies can be removed as part of follow up PRs as well though.
-----
The patch has three main components:
* Slightly modified `CustomData` API to make it work better with implicit
sharing:
* `CD_REFERENCE` and `CD_DUPLICATE` have been removed because they are
meaningless when implicit-sharing is used.
* `CD_ASSIGN` has been removed as well because it's not an allocation
type anyway. The functionality of using existing arrays as custom
data layers has not been removed though.
* This can still be done with `CustomData_add_layer_with_data` which
also has a new argument that allows passing in information about
whether the array is shared.
* `CD_FLAG_NOFREE` has been removed because it's no longer necessary. It
only existed because of `CD_REFERENCE`.
* `CustomData_copy` and `CustomData_merge` have been split up into a
functions that do copy the actual attribute values and those that do
not. The latter functions now have the `_layout` suffix
(e.g. `CustomData_copy_layout`).
* Changes in `customdata.cc` to make it actually use implicit-sharing.
* Changes in various other files to adapt to the changes in `BKE_customdata.h`.
Pull Request: blender/blender#106228
Implements #95967.
Currently the `MPoly` struct is 12 bytes, and stores the index of a
face's first corner and the number of corners/verts/edges. Polygons
and corners are always created in order by Blender, meaning each
face's corners will be after the previous face's corners. We can take
advantage of this fact and eliminate the redundancy in mesh face
storage by only storing a single integer corner offset for each face.
The size of the face is then encoded by the offset of the next face.
The size of a single integer is 4 bytes, so this reduces memory
usage by 3 times.
The same method is used for `CurvesGeometry`, so Blender already has
an abstraction to simplify using these offsets called `OffsetIndices`.
This class is used to easily retrieve a range of corner indices for
each face. This also gives the opportunity for sharing some logic with
curves.
Another benefit of the change is that the offsets and sizes stored in
`MPoly` can no longer disagree with each other. Storing faces in the
order of their corners can simplify some code too.
Face/polygon variables now use the `IndexRange` type, which comes with
quite a few utilities that can simplify code.
Some:
- The offset integer array has to be one longer than the face count to
avoid a branch for every face, which means the data is no longer part
of the mesh's `CustomData`.
- We lose the ability to "reference" an original mesh's offset array
until more reusable CoW from #104478 is committed. That will be added
in a separate commit.
- Since they aren't part of `CustomData`, poly offsets often have to be
copied manually.
- To simplify using `OffsetIndices` in many places, some functions and
structs in headers were moved to only compile in C++.
- All meshes created by Blender use the same order for faces and face
corners, but just in case, meshes with mismatched order are fixed by
versioning code.
- `MeshPolygon.totloop` is no longer editable in RNA. This API break is
necessary here unfortunately. It should be worth it in 3.6, since
that's the best way to allow loading meshes from 4.0, which is
important for an LTS version.
Pull Request: blender/blender#105938
The goal is to solve confusion of the "All rights reserved" for licensing
code under an open-source license.
The phrase "All rights reserved" comes from a historical convention that
required this phrase for the copyright protection to apply. This convention
is no longer relevant.
However, even though the phrase has no meaning in establishing the copyright
it has not lost meaning in terms of licensing.
This change makes it so code under the Blender Foundation copyright does
not use "all rights reserved". This is also how the GPL license itself
states how to apply it to the source code:
<one line to give the program's name and a brief idea of what it does.>
Copyright (C) <year> <name of author>
This program is free software ...
This change does not change copyright notice in cases when the copyright
is dual (BF and an author), or just an author of the code. It also does
mot change copyright which is inherited from NaN Holding BV as it needs
some further investigation about what is the proper way to handle it.
This makes the APIs more correct and simplifies debugging, because
some debuggers can now show the enum name instead of the integer.
Pull Request: blender/blender#106268
Implements #102359.
Split the `MLoop` struct into two separate integer arrays called
`corner_verts` and `corner_edges`, referring to the vertex each corner
is attached to and the next edge around the face at each corner. These
arrays can be sliced to give access to the edges or vertices in a face.
Then they are often referred to as "poly_verts" or "poly_edges".
The main benefits are halving the necessary memory bandwidth when only
one array is used and simplifications from using regular integer indices
instead of a special-purpose struct.
The commit also starts a renaming from "loop" to "corner" in mesh code.
Like the other mesh struct of array refactors, forward compatibility is
kept by writing files with the older format. This will be done until 4.0
to ease the transition process.
Looking at a small portion of the patch should give a good impression
for the rest of the changes. I tried to make the changes as small as
possible so it's easy to tell the correctness from the diff. Though I
found Blender developers have been very inventive over the last decade
when finding different ways to loop over the corners in a face.
For performance, nearly every piece of code that deals with `Mesh` is
slightly impacted. Any algorithm that is memory bottle-necked should
see an improvement. For example, here is a comparison of interpolating
a vertex float attribute to face corners (Ryzen 3700x):
**Before** (Average: 3.7 ms, Min: 3.4 ms)
```
threading::parallel_for(loops.index_range(), 4096, [&](IndexRange range) {
for (const int64_t i : range) {
dst[i] = src[loops[i].v];
}
});
```
**After** (Average: 2.9 ms, Min: 2.6 ms)
```
array_utils::gather(src, corner_verts, dst);
```
That's an improvement of 28% to the average timings, and it's also a
simplification, since an index-based routine can be used instead.
For more examples using the new arrays, see the design task.
Pull Request: blender/blender#104424
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.
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: blender/blender#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: blender/blender#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: blender/blender#104422
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.
In 6514bb05ea I misinterpreted the function's intended
behavior when there was already an existing active layer. The data from
the active layer is just meat to be copied, the function should always
add a new attribute.
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
Cycles uses the "split faces" mesh function to support sharp edges
and auto-smooth. However, 75ad8da1ea updated that
function to ignore the edges that are explicitly tagged as sharp and
only use the edge angle. Fix by taking the attribute into account too.
As described in #95966, replace the `ME_EDGEDRAW` flag with a bit
vector in mesh runtime data. Currently the the flag is only ever set
to false for the "optimal display" feature of the subdivision surface
modifier. When creating an "original" mesh in the main data-base,
the flag is always supposed to be true.
The bit vector is now created by the modifier only as necessary, and
is cleared for topology-changing operations. This fixes incorrect
interpolation of the flag as noted in #104376. Generally it isn't
possible to interpolate it through topology-changing operations.
After this, only the seam status needs to be removed from edges before
we can replace them with the generic `int2` type (or something similar)
and reduce memory usage by 1/3.
Related:
- 10131a6f62
- 145839aa42
In the future `BM_ELEM_DRAW` could be removed as well. Currently it is
used and aliased by other defines in some non-obvious ways though.
Pull Request #104417
Currently you can retrieve a mutable array from a const CustomData.
That makes code unsafe since the compiler can't check for correctness
itself. Fix that by introducing a separate function to retrieve mutable
arrays from CustomData. The new functions have the `_for_write`
suffix that make the code's intention clearer.
Because it makes retrieving write access an explicit step, this change
also makes proper copy-on-write possible for attributes.
Notes:
- The previous "duplicate referenced layer" functions are redundant
with retrieving layers with write access
- The custom data functions that give a specific index only have
`for_write` to simplify the API
Differential Revision: https://developer.blender.org/D14140
Move the `ME_SHARP` flag for mesh edges to a generic boolean
attribute. This will help allow changing mesh edges to just a pair
of integers, giving performance improvements. In the future it could
also give benefits for normal calculation, which could more easily
check if all or no edges are marked sharp, which is helpful considering
the plans in T93551.
The attribute is generally only allocated when it's necessary. When
leaving edit mode, it will only be created if an edge is marked sharp.
The data can be edited with geometry nodes just like a regular edge
domain boolean attribute.
The attribute is named `sharp_edge`, aiming to reflect the similar
`select_edge` naming and to allow a future `sharp_face` name in
a separate commit.
Ref T95966
Differential Revision: https://developer.blender.org/D16921
Currently the `MLoopUV` struct stores UV coordinates and flags related
to editing UV maps in the UV editor. This patch changes the coordinates
to use the generic 2D vector type, and moves the flags into three
separate boolean attributes. This follows the design in T95965, with
the ultimate intention of simplifying code and improving performance.
Importantly, the change allows exporters and renderers to use UVs
"touched" by geometry nodes, which only creates generic attributes.
It also allows geometry nodes to create "proper" UV maps from scratch,
though only with the Store Named Attribute node for now.
The new design considers any 2D vector attribute on the corner domain
to be a UV map. In the future, they might be distinguished from regular
2D vectors with attribute metadata, which may be helpful because they
are often interpolated differently.
Most of the code changes deal with passing around UV BMesh custom data
offsets and tracking the boolean "sublayers". The boolean layers are
use the following prefixes for attribute names: vert selection: `.vs.`,
edge selection: `.es.`, pinning: `.pn.`. Currently these are short to
avoid using up the maximum length of attribute names. To accommodate
for these 4 extra characters, the name length limit is enlarged to 68
bytes, while the maximum user settable name length is still 64 bytes.
Unfortunately Python/RNA API access to the UV flag data becomes slower.
Accessing the boolean layers directly is be better for performance in
general.
Like the other mesh SoA refactors, backward and forward compatibility
aren't affected, and won't be changed until 4.0. We pay for that by
making mesh reading and writing more expensive with conversions.
Resolves T85962
Differential Revision: https://developer.blender.org/D14365
**Changes**
As described in T93602, this patch removes all use of the `MVert`
struct, replacing it with a generic named attribute with the name
`"position"`, consistent with other geometry types.
Variable names have been changed from `verts` to `positions`, to align
with the attribute name and the more generic design (positions are not
vertices, they are just an attribute stored on the point domain).
This change is made possible by previous commits that moved all other
data out of `MVert` to runtime data or other generic attributes. What
remains is mostly a simple type change. Though, the type still shows up
859 times, so the patch is quite large.
One compromise is that now `CD_MASK_BAREMESH` now contains
`CD_PROP_FLOAT3`. With the general move towards generic attributes
over custom data types, we are removing use of these type masks anyway.
**Benefits**
The most obvious benefit is reduced memory usage and the benefits
that brings in memory-bound situations. `float3` is only 3 bytes, in
comparison to `MVert` which was 4. When there are millions of vertices
this starts to matter more.
The other benefits come from using a more generic type. Instead of
writing algorithms specifically for `MVert`, code can just use arrays
of vectors. This will allow eliminating many temporary arrays or
wrappers used to extract positions.
Many possible improvements aren't implemented in this patch, though
I did switch simplify or remove the process of creating temporary
position arrays in a few places.
The design clarity that "positions are just another attribute" brings
allows removing explicit copying of vertices in some procedural
operations-- they are just processed like most other attributes.
**Performance**
This touches so many areas that it's hard to benchmark exhaustively,
but I observed some areas as examples.
* The mesh line node with 4 million count was 1.5x (8ms to 12ms) faster.
* The Spring splash screen went from ~4.3 to ~4.5 fps.
* The subdivision surface modifier/node was slightly faster
RNA access through Python may be slightly slower, since now we need
a name lookup instead of just a custom data type lookup for each index.
**Future Improvements**
* Remove uses of "vert_coords" functions:
* `BKE_mesh_vert_coords_alloc`
* `BKE_mesh_vert_coords_get`
* `BKE_mesh_vert_coords_apply{_with_mat4}`
* Remove more hidden copying of positions
* General simplification now possible in many areas
* Convert more code to C++ to use `float3` instead of `float[3]`
* Currently `reinterpret_cast` is used for those C-API functions
Differential Revision: https://developer.blender.org/D15982
Previously, the lifetimes of anonymous attributes were determined by
reference counts which were non-deterministic when multiple threads
are used. Now the lifetimes of anonymous attributes are handled
more explicitly and deterministically. This is a prerequisite for any kind
of caching, because caching the output of nodes that do things
non-deterministically and have "invisible inputs" (reference counts)
doesn't really work.
For more details for how deterministic lifetimes are achieved, see D16858.
No functional changes are expected. Small performance changes are expected
as well (within few percent, anything larger regressions should be reported as
bugs).
Differential Revision: https://developer.blender.org/D16858
Attributes are unifying around a name-based API, and we would like to
be able to move away from CustomData in the future. This patch moves
the identification of active and fallback (render) color attributes
to strings on the mesh from flags on CustomDataLayer. This also
removes some ugliness used to retrieve these attributes and maintain
the active status.
The design is described more here: T98366
The patch keeps forward compatibility working until 4.0 with
the same method as the mesh struct of array refactors (T95965).
The strings are allowed to not correspond to an attribute, to allow
setting the active/default attribute independently of actually filling
its data. When applying a modifier, if the strings don't match an
attribute, they will be removed.
The realize instances / join node and join operator take the names from
the first / active input mesh. While other heuristics may be helpful
(and could be a future improvement), just using the first is simple
and predictable.
Differential Revision: https://developer.blender.org/D15169
Recently a new geometry node for splitting edges was added in D16399.
However, there was already a similar implementation in mesh.cc that was
mainly used to fake auto smooth support in Cycles by splitting sharp
edges and edges around sharp faces.
While there are still possibilities for optimization in the new code,
the implementation is safer and simpler, multi-threaded, and aligns
better with development plans for caching topology on Mesh and other
recent developments with attributes.
This patch removes the old code and moves the node implementation to
the geometry module so it can be used in editors and RNA. The "free
loop normals" argument is deprecated now, since it was only an internal
optimization exposed for Cycles.
The new mesh `editors` function creates an `IndexMask` of edges to
split by reusing some of the code from the corner normal calculation.
This change will help to simplify the changes in D16530 and T102858.
Differential Revision: https://developer.blender.org/D16732
Don't use the same "context" struct for tagging sharp edges from auto-
smooth / poly flags and actually calculating face corner normals. That
required more arguments, and it required breaking const slightly to
reuse the code. Also split apart pre-populating corner normals
with vertex normals, since it isn't related at all and is only used
in one code path.
As part of T95966, this patch moves loose edge information out of the
flag on each edge and into a new lazily calculated cache in mesh
runtime data. The number of loose edges is also cached, so further
processing can be skipped completely when there are no loose edges.
Previously the `ME_LOOSEEDGE` flag was updated on a "best effort"
basis. In order to be sure that it was correct, you had to be sure
to call `BKE_mesh_calc_edges_loose` first. Now the loose edge tag
is always correct. It also doesn't have to be calculated eagerly
in various places like the screw modifier where the complexity
wasn't worth the theoretical performance benefit.
The patch also adds a function to eagerly set the number of loose
edges to zero to avoid building the cache. This is used by various
primitive nodes, with the goal of improving drawing performance.
This results in a few ms shaved off extracting draw data for some
large meshes in my tests.
In the Python API, `MeshEdge.is_loose` is no longer editable.
No built-in addons set the value anyway. The upside is that
addons can be sure the data is correct based on the mesh.
**Tests**
There is one test failure in the Python OBJ exporter: `export_obj_cube`
that happens because of existing incorrect versioning. Opening the
file in master, all the edges were set to "loose", which is fixed
by this patch.
Differential Revision: https://developer.blender.org/D16504
Currently there are both "EDGERENDER" and "EDGEDRAW" flags, which are
almost always used together. Both are runtime data and not exposed to
RNA, used to skip drawing some edges after the subdivision surface
modifier. The render flag is a relic of the Blender internal renderer.
This commit removes the render flag and replaces its uses with the
draw flag.
This is the conventional way of dealing with unused arguments in C++,
since it works on all compilers.
Regex find and replace: `UNUSED\((\w+)\)` -> `/*$1*/`
Using the attribute name semantics from T97452, this patch moves the
selection status of mesh elements from the `SELECT` of vertices, and
edges, and the `ME_FACE_SEL` of faces to generic boolean attribute
Storing this data as generic attributes can significantly simplify and
improve code, as described in T95965.
The attributes are called `.select_vert`, `.select_edge`, and
`.select_poly`. The `.` prefix means they are "UI attributes",so they
still contain original data edited by users, but they aren't meant to
be accessed procedurally by the user in arbitrary situations. They are
also be hidden in the spreadsheet and the attribute list.
Until 4.0, the attributes are still written to and read from the mesh
in the old way, so neither forward nor backward compatibility are
affected. This means memory requirements will be increased by one byte
per element when selection is used. When the flags are removed
completely, requirements will decrease.
Further notes:
* The `MVert` flag is empty at runtime now, so it can be ignored.
* `BMesh` is unchanged, otherwise the change would be much larger.
* Many tests have slightly different results, since the selection
attribute uses more generic propagation. Previously you couldn't
really rely on edit mode selections being propagated procedurally.
Now it mostly works as expected.
Similar to 2480b55f21
Ref T95965
Differential Revision: https://developer.blender.org/D15795
This is very similar to D14077. There are two differences though.
First is that vertex creases are already stored in a separate layer,
and second is that we can now completely remove use of `Mesh.cd_flag`,
since that information is now inherent to whether the layers exist.
There are two functional differences here:
* Operators are used to add and remove layers instead of a property.
* The "crease" attribute can be created and removed by geometry nodes.
The second change should make various geometry nodes slightly faster,
since the "crease" attribute was always processed before. Creases are
now interpolated generically in the CustomData API too, which should
help maintain the values across edits better.
Meshes get an `edge_creases` RNA property like the existing vertex
property, to provide more efficient access to the data in Cycles.
One test failure is expected, where different rounding between float
the old char storage means that 5 additional points are scattered in
a geometry nodes test.
Differential Revision: https://developer.blender.org/D15927
As described in T95966, the goal is to move to a "struct of arrays"
approach rather than gathering an arbitrary set of data in hard-coded
structs. This has performance benefits, but also code complexity
benefits (this patch removes plenty of code, though the boilerplate
for the new operators outweighs that here).
To mirror the internal change, the options for storing mesh bevel
weights are converted into operators that add or remove the layer,
like for some other layers.
The most complex change is to the solidify modifier, where bevel
weights had special handling. Other than that, most changes are
removing clearing of the weights, boilerplate for the add/remove
operators, and removing the manual transfer of bevel weights
in bmesh - mesh conversion.
Eventually bevel weights can become a fully generic attribute,
but for now this patch aims to avoid most functional changes.
Bevel weights are still written and read from the mesh in the old way,
so neither forward nor backward compatibility are affected. As described
in T95965, writing in the old format will be done until 4.0.
Differential Revision: https://developer.blender.org/D14077
Use `verts` instead of `vertices` and `polys` instead of `polygons`
in the API added in 05952aa94d. This aligns better with
existing naming where the shorter names are much more common.
For copy-on-write, we want to share attribute arrays between meshes
where possible. Mutable pointers like `Mesh.mvert` make that difficult
by making ownership vague. They also make code more complex by adding
redundancy.
The simplest solution is just removing them and retrieving layers from
`CustomData` as needed. Similar changes have already been applied to
curves and point clouds (e9f82d3dc7, 410a6efb74). Removing use of
the pointers generally makes code more obvious and more reusable.
Mesh data is now accessed with a C++ API (`Mesh::edges()` or
`Mesh::edges_for_write()`), and a C API (`BKE_mesh_edges(mesh)`).
The CoW changes this commit makes possible are described in T95845
and T95842, and started in D14139 and D14140. The change also simplifies
the ongoing mesh struct-of-array refactors from T95965.
**RNA/Python Access Performance**
Theoretically, accessing mesh elements with the RNA API may become
slower, since the layer needs to be found on every random access.
However, overhead is already high enough that this doesn't make a
noticible differenc, and performance is actually improved in some
cases. Random access can be up to 10% faster, but other situations
might be a bit slower. Generally using `foreach_get/set` are the best
way to improve performance. See the differential revision for more
discussion about Python performance.
Cycles has been updated to use raw pointers and the internal Blender
mesh types, mostly because there is no sense in having this overhead
when it's already compiled with Blender. In my tests this roughly
halves the Cycles mesh creation time (0.19s to 0.10s for a 1 million
face grid).
Differential Revision: https://developer.blender.org/D15488
