This makes it available in Cycles standalone, and the implementation
can be shared with Blender. This also makes it possible to compute
tangents after tessellation for adaptive subdivision.
There is a difference in UV map tangents when there are no UVs. They
are now generated from object space coordinates instead of auto
texture space coordinates. This is more efficient, and a corner case
that we don't have to keep compatible.
Co-authored-by: Brecht Van Lommel <brecht@blender.org>
Pull Request: https://projects.blender.org/blender/cycles/pulls/25
Use the mesh wrapper mechanism from GPU subdivision to get the base mesh.
This can significantly reduce memory usage and render setup time if the
level was not manually set to zero.
Pull Request: https://projects.blender.org/blender/blender/pulls/135895
* Add SubdAttributeInterpolation class for linear attribute interpolation.
* Dicing computes ptex UV and face ID for interpolation.
* Simplify mesh storage of subd primitive counts
* Remove kernel code for subd attribute interpolation
* Remove patch table packing and upload
The old optimization adds a fair amount of complexity to the kernel, affecting
performance even when not using the feature. It's also not that useful as it
does not work for UVs that needs special interpolation. With this simpler code
it should be easier to make it feature complete.
Pull Request: https://projects.blender.org/blender/blender/pulls/135681
Replace `const char *` with `StringRef` for the API in `BKE_attribute.h`.
The benefits are slightly simpler code and possibly slightly improved
performance through avoiding the need to measure string length.
Pull Request: https://projects.blender.org/blender/blender/pulls/134183
The issue here is that motion_steps handling is a bit complex, and the
parallel synchronization of geometry does not play well with it.
The obvious result of this was a crash related to the main thread
checking attributes while the geometry sync was changing them, but
there was also another race condition that could result in ending up
with the wrong motion_steps.
Specific changes:
- Change place where `motion_steps` is set to avoid concurrent access
- Change the default `motion_steps` to zero, since they won't be
explicitly set if there's no motion now
- Don't skip `motion_steps` copy in `sync_X` since it's no longer set
in `sync_object` and we need to transfer the value in case it was set
to 3 by the velocity code since that's no longer the default
Pull Request: https://projects.blender.org/blender/blender/pulls/133669
Check was misc-const-correctness, combined with readability-isolate-declaration
as suggested by the docs.
Temporarily clang-format "QualifierAlignment: Left" was used to get consistency
with the prevailing order of keywords.
Pull Request: https://projects.blender.org/blender/blender/pulls/132361
* Use .empty() and .data()
* Use nullptr instead of 0
* No else after return
* Simple class member initialization
* Add override for virtual methods
* Include C++ instead of C headers
* Remove some unused includes
* Use default constructors
* Always use braces
* Consistent names in definition and declaration
* Change typedef to using
Pull Request: https://projects.blender.org/blender/blender/pulls/132361
This improve the API in multiple aspects:
* No need for an additional `lookup` call to get the current attribute. This
would internally iterate over all attributes again. This leads to O(n^2)
behavior. Note that there are still other reasons for O(n^2) behavior when
processing attributes (where n is the number of attributes).
* Remove the need to return a value from the iteration code to indicate that the
iteration should continue. This is now the default behavior. The iteration can
still be stopped by calling `iter.stop()`.
* Easier access to `is_builtin` property.
* Iterator callback only has a single parameter instead of two (of which one is
sometimes unused).
Pull Request: https://projects.blender.org/blender/blender/pulls/128128
Previously, the `AttributeIDRef` wrapper was needed because it also had to
contain a pointer to an `AnonymousAttributeID`. However, since
b279a6d703 this is not necessary anymore.
Therefore we can use "raw" `StringRef` now which reduces the mental overhead
when working with attributes and also simplifies code.
Pull Request: https://projects.blender.org/blender/blender/pulls/127140
Cycles can use a per face flag to determine if a face is smooth or flat,
and there is no need to use corner normals in such cases. So revert to
not doing that as before, which also saves a bit of memory.
There is a pre-existing issue where faces are split by sharp edges and
autosmooth, which is not solved by this. It's only fixing the regression.
In this case the object transform can use more motion steps, but the
geometry needs to have its motion steps fixed since the velocity
attribute completely overrides them.
Along with the 4.1 libraries upgrade, we are bumping the clang-format
version from 8-12 to 17. This affects quite a few files.
If not already the case, you may consider pointing your IDE to the
clang-format binary bundled with the Blender precompiled libraries.
Some common headers were including this. Separating the includes
will ideally lead to better conceptual separation between CustomData
and the attribute API too. Mostly the change is adding the file to
places where it was included indirectly before. But some code is
shuffled around to hopefully better places as well.
Each value is now out of the global namespace, so they can be shorter
and easier to read. Most of this commit just adds the necessary casting
and namespace specification. `enum class` can be forward declared since
it has a specified size. We will make use of that in the next commit.
Use the standard "elements_num" naming, and use the "corner" name rather
than the old "loop" name: `verts_num`, `edges_num`, and `corners_num`.
This matches the existing `faces_num` field which was already renamed.
Pull Request: https://projects.blender.org/blender/blender/pulls/116350
Make the naming consistent with the recent change from "loop" to
"corner". Avoid the need for a special type for these triangles by
conveying the semantics in the naming instead.
- `looptris` -> `corner_tris`
- `lt` -> `tri` (or `corner_tri` when there is less context)
- `looptri_index` -> `tri_index` (or `corner_tri_index`)
- `lt->tri[0]` -> `tri[0]`
- `Span<MLoopTri>` -> `Span<int3>`
- `looptri_faces` -> `tri_faces` (or `corner_tri_faces`)
If we followed the naming pattern of "corner_verts" and "edge_verts"
exactly, we'd probably use "tri_corners" instead. But that sounds much
worse and less intuitive to me.
I've found that by using standard vector types for this sort of data,
the commonalities with other areas become much clearer, and code ends
up being naturally more data oriented. Besides that, the consistency
is nice, and we get to mostly remove use of `DNA_meshdata_types.h`.
Pull Request: https://projects.blender.org/blender/blender/pulls/116238
The term `looptri` was used ambiguously for both single & arrays.
The term `tri` was also used, causing `tri->tri`.
Use terms:
- `looptris` for an array or when dealing with multiple items.
- `looptri` is used when dealing with a single item.
- `lt` for a single MLoopTri variables & arguments.
This was already a convention but not followed closely.
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
Since 34b4487844, attributes are always made mutable when
accessed from the RNA API. This can result in unnecessary copies, which
increases memory usage and reduces performance.
Cycles is the only user of the C++ RNA API, which we'd like to remove
in the future since it doesn't really make sense in the big picture.
Hydra is now a better alternative for external render engines.
To start that change and fix the unnecessary copies, this commit
moves to use Blender headers directly for accessing attribute and
other geometry data. This also removes the few places that still had
overhead from the RNA API after the changes ([0]) in 3.6. In a simple
test with a large grid, I observed a 1.76x performance improvement,
from 1.04 to 0.59 seconds to extract the mesh data to Cycles.
[0]: https://wiki.blender.org/wiki/Reference/Release_Notes/3.6/Cycles#Performance
Pull Request: https://projects.blender.org/blender/blender/pulls/112306
Implements part of #101689.
The "poly" name was chosen to distinguish the `MLoop` + `MPoly`
combination from the `MFace` struct it replaced. Those two structures
persisted together for a long time, but nowadays `MPoly` is gone, and
`MFace` is only used in some legacy code like the particle system.
To avoid unnecessarily using a different term, increase consistency
with the UI and with BMesh, and generally make code a bit easier to
read, this commit replaces the `poly` term with `poly`. Most variables
that use the term are renamed too. `Mesh.totface` and `Mesh.fdata` now
have a `_legacy` suffix to reduce confusion. In a next step, `pdata`
can be renamed to `face_data` as well.
Pull Request: https://projects.blender.org/blender/blender/pulls/109819
Store subdivision surface creases in two new named float attributes:
- `crease_vert`
- `crease_edge`
This is similar to 2a56403cb0.
The attributes are naming conventions, so their data type and domain
aren't enforced, and may be interpolated when necessary. Editing tools
and the subdivision surface modifier use the hard-coded name. It might
be best if these were edited as generic attributes in the future, but
in the meantime using generic attributes helps.
The attributes are visible in the list, which is how they're now meant
to be removed. They are now interchangeable with any tool that works
with the generic attribute system-- even tools like vertex paint can
affect creases now.
This is a breaking change. Forward compatibility isn't preserved for
versions before 3.6, and the `crease` property in RNA is removed in
favor of making a smaller API surface area with just the attribute API.
`Mesh.vertex_creases` and `Mesh.edge_creases` now just return the
matching attribute if possible, and are now implemented in Python.
New functions `*ensure` and `*remove` also replace the operators to
add and remove the layers for Python.
A few extrude node test files have to be updated because of different
(now generic) attribute interpolation behavior.
Pull Request: https://projects.blender.org/blender/blender/pulls/108089
For derived mesh triangulation information, currently the three face
corner indices are stored in the same struct as index of the mesh
polygon the triangle is part of. While those pieces of information are
often used together, they often aren't, and combining them prevents
the indices from being used with generic utilities. It also means that
1/3 more memory has to be written when recalculating the triangulation
after deforming the mesh, and that the entire triangle data has to be
read when only the polygon indices are needed.
This commit splits the polygon index into a separate cache on `Mesh`.
The triangulation data isn't saved to files, so this doesn't affect
.blend files at all.
In a simple test deforming a mesh with geometry nodes, the time used
to recalculate the triangulation reduced from 2.0 ms to 1.6 ms,
increasing overall FPS from 14.6 to 15.
Pull Request: https://projects.blender.org/blender/blender/pulls/106774
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
This type will be used to store mesh edges in #106638, but it could
be used for anything else too. This commit adds support for:
- The new type in the Python API
- Editing the type in the edit mode "Attribute Set" operator
- Rendering the type in EEVEE and Cycles for all geometry types
- Geometry nodes attribute interpolation and mixing
- Viewing the type in the spreadsheet and using row filters
The attribute uses the `blender::int2` type in most code, and
the `vec2i` DNA type in C code when necessary. The enum names
are based on `INT32_2D` for consistency with `INT8` and `INT32`.
Pull Request: https://projects.blender.org/blender/blender/pulls/106677
Similar to 4bcd59d644. This probably got worse recently with
the generic attribute refactors for `Mesh`, but the final performance is
probably much better than older versions too.
Timings extracting attributes from a 16 million vertex grid (seconds):
- Corner float attribute: 0.72 -> 0.19
- Face float attribute: 0.60 -> 0.07
- UV map: 3.18 -> 0.05
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
Use raw Blender structs and mesh data rather than using the RNA API.
There isn't any benefit from using the RNA when Cycles is compiled
with Blender anyway, and a profile showed that the majority of time
was spent in Blender RNA API functions.
This gives a significant improvement in performance when ingesting
meshes. Here are some tests of the runtime of the `create_mesh`
function (in seconds):
| | Before | After |
| ------------------------- | ------ | ----- |
| Grid | 0.66 | 0.11 |
| Many realized cubes | 2.60 | 0.48 |
| Large curve to mesh setup | 4.18 | 1.14 |
Also change to resizing the arrays and filling them by index rather
than appending. This makes the parallel aspect of the logic clearer,
and makes the loops easier to parallelize in the future, and makes
it easier to have a performance benefit when an attribute like
`sharp_face` doesn't exist.
Pull Request: https://projects.blender.org/blender/blender/pulls/106275
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
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
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
**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
The `render_color_index` skips attributes with different types
and domains in order to give the proper order for the UI list.
That is a different than an index in the group of all attributes.
The most solid solution I could think of is exposing the name of
the default color attribute. It's "solid" because we always address
attributes by name internally. Doing something different is bound
to create problems. It's also aligned with the design in T98366 and
D15169.
Another option would be to change the way the "attribute index"
is incremented in Cycles. That would be a valid solution, but would
be more complex and annoying.
For consistency, I also exposed the name of the active color attribute
the same way, though it isn't necessary to fix this particular bug.
The properties aren't editable, that can come in 3.5 as part of D15169.
Differential Revision: https://developer.blender.org/D16769
Caused by a8a454287a which assumed it was possible
to access the raw data of the edge creases layer. Also allow
processing vertex creases even if there aren't any edge creases.
