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: https://projects.blender.org/blender/blender/pulls/106638
The extrude node resizes an existing mesh, but doesn't initialize new
data for most non-generic data types like shape keys or freestyle tags,
or custom normals. The split edges node doesn't process some
similar vertex data too.
In the future this data can become generic attributes, or it can be
supported in the nodes anyway. But now the new data is un-initialized
after being allocated.
Fixes#106926
The position attribute has special meaning for point clouds, and
meshes and curves have access methods for the attribute as well.
This saves boilerplate and gives more consistency between types.
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: https://projects.blender.org/blender/blender/pulls/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: https://projects.blender.org/blender/blender/pulls/105938
Vertex positions and faces aren't changed, so most caches shouldn't
need to be tagged. This removes unnecessary re-computation of bounds,
triangulation, loose edges, etc.
Pull Request: https://projects.blender.org/blender/blender/pulls/106250
Adds the ability to pack UVs back into the original bounding box.
Choose UV Editor > Menu > UV > Pack Islands
Then change "Pack To" to "Original bounding box"
For example
```
OIIOOutputDriver::~OIIOOutputDriver()
{
}
```
becomes
```
OIIOOutputDriver::~OIIOOutputDriver() {}
```
Saves quite some vertical space, which is especially handy for
constructors.
Pull Request: https://projects.blender.org/blender/blender/pulls/105594
The overall goal is to use implicit-sharing in many places in Blender
that currently do unnecessary copies. See #95845 for more details.
This commit only adds the base data structures in blenlib and uses those
in `GeometrySet` and `AnonymousAttributeID`, which used a more ad-hoc
version of implicit sharing already. #105994 lists some more places where
support for implicit sharing can be added (most notably: custom data layers).
Pull Request: https://projects.blender.org/blender/blender/pulls/105994
Improvements to packing efficiency and updating UV packing API.
* Add #pack_islands_alpaca_rotate, the fast alpaca-style packer with rotation.
* Update heuristic for sorting islands based on longest edge.
(Improves pack efficiency when rotation is enabled.)
* Add `aspect_y` to UV Packing API, to support non-square materials in the future.
Pull Request: https://projects.blender.org/blender/blender/pulls/105977
When all of the input meshes have no loose edges, the output won't have
any either, but finding that out for the output is much more expensive.
Copy this tag to the output mesh to save processing time when drawing.
In my test creating 1 million instances of a 16 face mesh, this changed
the time for the draw cache loose geometry extraction from 220 ms to
131 ms.
For now, only do this when the loose edges of the inputs are already
cached (primitive nodes, for example). This avoids paying the cost of
calculation when we don't know it will be necessary.
AABB aligned quads would defeat the "witness" accelerator when
using the xatlas packing strategy.
This change reorders the search to allow use of the "witness" technique.
Standardize naming, use spans and references for input parameters,
and improve documentation. Now the functions expect the lookups to
succeed as well, they will fail and assert otherwise.
The functions are also simple enough that it likely makes sense to keep
them all inlined
Add `index_range()` and `is_empty()` functions, rename `ranges_num()`
to `size()` (clarifying the final extra integer as an implementation
detail). Also remove the `size(index)` function which gave almost the
same assembly as `[index].size()` (https://godbolt.org/z/PYzqYs3Kr).
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: https://projects.blender.org/blender/blender/pulls/104424
Geometry Nodes: SDF Volume nodes milestone 1
Adds initial support for SDF volume creation and manipulation.
`SDF volume` is Blender's name of an OpenVDB grid of type Level Set.
See the discussion about naming in #91668.
The new nodes are:
- Mesh to SDF Volume: Converts a mesh to an SDF Volume
- Points to SDF Volume: Converts points to an SDF Volume
- Mean Filter SDF Volume: Applies a Mean Filter to an SDF
- Offset SDF Volume: Applies an offset to an SDF
- SDF Volume Sphere: Creates an SDF Volume in the shape of a sphere
For now an experimental option `New Volume Nodes` needs to be
enabled in Blender preferences for the nodes to be visible.
See the current work plan for Volume Nodes in #103248.
Pull Request: https://projects.blender.org/blender/blender/pulls/105090
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
