Split much of BKE_pbvh.h into BKE_pbvh_api.hh.
BKE_pbvh.h is included by BKE_paint.h, which in
turn is included by large amounts of code including
RNA.
This makes it extremely difficult to change
or clean up the PBVH API, since each modification
of BKE_pbvh.h can take 20-30 minutes to compile,
even on a quad-core system with an SSD. This
commit fixes that by moving most of BKE_pbvh.h
into another file and just having the core,
external-facing interfaces in BKE_pbvh.h.
A lot of files were missing copyright field in the header and
the Blender Foundation contributed to them in a sense of bug
fixing and general maintenance.
This change makes it explicit that those files are at least
partially copyrighted by the Blender Foundation.
Note that this does not make it so the Blender Foundation is
the only holder of the copyright in those files, and developers
who do not have a signed contract with the foundation still
hold the copyright as well.
Another aspect of this change is using SPDX format for the
header. We already used it for the license specification,
and now we state it for the copyright as well, following the
FAQ:
https://reuse.software/faq/
Combine the newer less efficient C++ implementations and the older
less convenient C functions. The maps now contain one large array of
indices, split into groups by a separate array of offset indices.
Though performance of creating the maps is relatively unchanged, the
new implementation uses 4 bytes less per source element than the C
maps, and 20 bytes less than the newer C++ functions (which also
had more overhead with larger N-gons). The usage syntax is simpler
than the C functions as well.
The reduced memory usage is helpful for when these maps are cached
in the near future. It will also allow sharing the offsets between
maps for different domains like vertex to corner and vertex to face.
A simple `GroupedSpan` class is introduced to make accessing the
topology maps much simpler. It combines offset indices and a separate
span, splitting it into chunks in an efficient way.
Pull Request: https://projects.blender.org/blender/blender/pulls/107861
looptris were referred to as both tris & faces, sometimes polygons
were referred to as faces too. Was especially error prone with
callbacks that took both a tri and a tri_i arguments.
Sometimes tri_i represented a looptri index, other times the corner of
the triangle from 0-2. Causing expressions such as:
`args->mlooptri[tri].tri[tri_i]`
- Rename tri & tri_index -> looptri_i.
- Rename faces -> looptris.
- Rename face_index/poly_index/poly -> poly_i.
- Declare looptri_i at the start of the loop and reuse it,
in some cases it was declared with args->prim_indices[i] being
used as well.
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
Cleaned up sculpt code to store lists of `PBVHNodes` with
`blender::Vector` instead of simple pointer arrays. This is much
simpler and eliminates memory leaks caused by forgetting to free
the result of `BKE_pbvh_search_gather`.
Notes:
* `BKE_pbvh_search_gather` is now `blender::pbvh::search_gather`.
* `FilterCache` and `ExpandCache` have ownership over their .nodes
members; as a result they're no longer pure C structs and
are allocated with `MEM_new`/`MEM_delete`.
* The word 'totnode' no longer occurs anywhere in
`source/blender/editors/sculpt_paint`
Todo (not for this PR): create a new properly C++ task API for sculpt
(with lambdas) and use it for brushes.
Pull Request: https://projects.blender.org/blender/blender/pulls/106884
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
This allows adding spans, arrays, etc. directly to SculptSession, which
simplifies accessing mesh data, especially in #105938. A few files
aren't moved to C++ yes, so I had to add three C accessor functions.
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
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.
`PBVH_Leaf` nodes are now split into a new `PBVH_TexLeaf`
node type when using the paint brush. These nodes are
split by image pixels, not triangles. This greatly
increases performance when working with large
textures on low-poly meshes.
Reviewed By: Jeroen Bakker
Differential Revision: https://developer.blender.org/D14900
Ref: D14900
Mesh islands (shells) are now calculated on an as-needed
basis and cached inside of a temp attribute,
`sculpt_topology_island_key`. This attribute is updated
as needed when geometry changes (e.g. the trim brush)
or when mesh visibility changes.
This replaces the old behavior where the "topology" automasking
mode would walk the entire mesh on every stroke.
**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
PBVH draw code now builds coarse triangle index buffers
for multires. Note that the coarse grids can be at any
multires depth but is currently hardcoded to 1.
{F13294314}
# Process
In the pixel extraction process a larger domain will be extracted then the input mesh.
The borders of uv islands are extended with connected geometry of the input mesh.
The extended mesh is then fed into the pixel extraction process.
A mask is used to limit the extraction so UV islands will not overlap.
Input UV islands.
{F13206401}
Extended UV Island (only one showing).
{F13288764}
This patch doesn't include fixing uv seams at non-manifold edges (like suzannes eyes) as that
would require a different approach (edge extending or pixel copy-ing). The later has already been
implemented in D14702, but should be revisited to only use do the non-manifold edge fixing.
This patch supports fixing UV seams across UDIM textures.
There might be an issue when using a single texture on multiple uv maps.
Reviewed By: brecht, joeedh, JulienKaspar
Maniphest Tasks: T97352
Differential Revision: https://developer.blender.org/D14970
Currently the face set of every single face is saved for every sculpt undo step.
When only changing the face sets of a small section of the mesh, this can be quite
wasteful. It also makes face sets a special case compare to all other sculpt undo step
types, which makes the whole system more complex and harder to improve.
Fixes T101203.
Reviewed By: Hans Goudey
Differential Revision: https://developer.blender.org/D16224
Ref D16224
Currently the face set of every single face is saved for every sculpt undo step.
When only changing the face sets of a small section of the mesh, this can be quite
wasteful. It also makes face sets a special case compare to all other sculpt undo step
types, which makes the whole system more complex and harder to improve.
Fixes T101203.
Reviewed By: Hans Goudey
Differential Revision: https://developer.blender.org/D16224
Ref D16224
Wrote a new API method, BKE_pbvh_sync_visibility_from_verts
that flushes vertex hidden flags to edges & faces.
Fixes not being able to sculpt outside a face set after
undoing the fkey hide-all-but-this operator.
Wrote a new API method, BKE_pbvh_sync_visibility_from_verts
that flushes vertex hidden flags to edges & faces.
Fixes not being able to sculpt outside a face set after
undoing the fkey hide-all-but-this operator.
Remove `private:` from the PBVHFaceIter. This is not really a C++
class, and the C++ code generates a lot of warnings about unused
fields.
Also mark function static and run clang-format.
This patch adds basic face iterators to the sculpt API. The interface is similar to the existing vertex iterators. It's not C++ (though it does mark private fields in PBVHFaceIter as private if compiling under C++).
Example:
```
PBVHFaceIter fd;
BKE_pbvh_face_iter_begin(pbvh, node, fd) {
/* Face reference and face index */
PBVHFaceRef face = fd->face;
int face_index = fd->index;
/* Can read and modify hide flag if it exist (it may not) */
if (fd->hide) {
*fd->hide ^= true; /* toggle hide */
}
/* Can read and modify face set if it exists */
if (fd->face_set) {
*fd->face_set = something;
}
/*Can read vertices*/
for (int i=0; i<fd.verts_num; i++) {
float *co = SCULPT_vertex_co_get(ss, fd.verts[i]);
}
}
BKE_pbvh_face_iter_end(fd);
```
Reviewed By: Brecht Von Lommen and Hans Goudey
Differential Revision: https://developer.blender.org/D16225
Ref D16225
BKE_sculpt_mask_layers_ensure now takes a depsgraph argument and
will evaluate the depsgraph if a multires mask layer is added.
This is necassary to update the multires runtime data so that
pbvh knows it has a grids mask layer.
Also added code to update pbvh->gridkey.
PBVH_FACES and PBVH_GRIDS do not store faces directly in nodes;
instead they store 'primitives', which are tesselation triangles
for PBVH_FACES and grids (which are per-loop) for PBVH_GRIDS.
Primitives from the same face could sometimes end up in different
PBVH nodes. This is now prevented in two ways:
* All primitives of the same face are given the same boundary
during PBVH build. This prevents them from being swapped
away from each other during partitioning.
* build_sub adjusts the final partition midpoint to fall
between primitives of different faces.
Cleaned up Dyntopo original triangle API (which is deprecated):
* BMVerts for original triangles are now stored.
* BKE_pbvh_bmesh_update_topology now handles original triangle
* data properly.
* BKE_pbvh_bmesh_node_save_orig can now initialize the original
coordinates from the current BMLogEntry.
* Ray casting of original data now returns active vertex.
Should fix various random crashes.
Hopefully this will fix a number of bugs.
Even if multires in sculpt mode doesn't yet support color
attributes, we should at least upload white color to avoid
making everything black.
Also fixed a bug where multires PBVHs didn't have access to
their CustomData attribute layout, which PBVH draw needs.
Rewrite PBVH draw to allocate attributes into individual VBOs.
The old system tried to create a single VBO that could feed
every open viewport. This required uploading every color and
UV attribute to the viewport whether needed or not, often exceeding
the VBO limit.
This new system creates one VBO per attribute. Each attribute layout is
given its own GPU batch which is cached inside the owning PBVH node.
Notes:
* This is a full C++ rewrite. The old code is still there; ripping it out
can happen later.
* PBVH nodes now have a collection of batches, PBVHBatches, that keeps
track of all the batches inside the node.
* Batches are built exclusively from a list of attributes.
* Each attribute has its own VBO.
* Overlays, workbench and EEVEE can all have different attribute
layouts, each of which will get its own batch.
Reviewed by: Clement Foucault
Differential Revision: https://developer.blender.org/D15428
Ref D15428
New unified attribute API for sculpt code.
= Basic Design =
The sculpt attribute API can create temporary or permanent attributes (only supported in `PBVH_FACES` mode). Attributes are created via `BKE_sculpt_attribute_ensure.`
Attributes can be explicit CustomData attributes or simple array-based pseudo-attributes (this is useful for PBVH_GRIDS and PBVH_BMESH).
== `SculptAttributePointers` ==
There is a structure in `SculptSession` for convenience attribute pointers, `ss->attrs`. Standard attributes should assign these; the attribute API will automatically clear them when the associated attributes are released. For example, the automasking code stores its factor attribute layer in `ss->attrs.automasking_factor`.
== Naming ==
Temporary attributes should use the SCULPT_ATTRIBUTE_NAME macro for naming, it takes an entry in `SculptAttributePointers` and builds a layer name.
== `SculptAttribute` ==
Attributes are referenced by a special `SculptAttribute` structure, which holds
all the info needed to look up elements of an attribute at run time.
All of these structures live in a preallocated flat array in `SculptSession`, `ss->temp_attributes`. This is extremely important. Since any change to the `CustomData` layout can in principle invalidate every extant `SculptAttribute`, having them all in one block of memory whose location doesn't change allows us to update them transparently.
This makes for much simpler code and eliminates bugs. To see why this is tricky to get right, imagine we want to create three attributes in PBVH_BMESH mode and we provide our own `SculptAttribute` structs for the API to fill in. Each new layer will invalidate the `CustomData` block offsets in the prior one, leading to memory corruption.
Reviewed by: Brecht Van Lommel
Differential Revision: https://developer.blender.org/D15496
Ref D15496
Whether faces are hidden and face sets are orthogonal concepts, but
currently sculpt mode stores them together in the face set array.
This means that if anything is hidden, there must be face sets,
and if there are face sets, we have to keep track of what is hidden.
In other words, it adds a bunch of redundant work and state tracking.
On the user level it's nice that face sets and hiding are consistent,
but we don't need to store them together to accomplish that.
This commit uses the `".hide_poly"` attribute from rB2480b55f216c to
read and change hiding in sculpt mode. Face sets don't need to be
negative anymore, and a bunch of "face set <-> hide status" conversion
can be removed. Plus some other benefits:
- We don't need to allocate either array quite as much.
- The hide status can be read from 1/4 the memory as face sets.
- Updates when entering or exiting sculpt mode can be removed.
- More opportunities for early-outs when nothing is hidden.
- Separating concerns makes sculpt code more obvious.
- It will be easier to convert face sets into a generic int attribute.
Differential Revision: https://developer.blender.org/D15950
Caused by b5f7af31d6, which exposed the fact that the PBVH wasn't
retrieving the updated hide status attributes if they were allocated in
sculpt mode. Previously the attributes were always allocated when
entering sculpt mode.
corresponding data layers and using their values for computations.
Avoiding that should increase performance in many operations that
would otherwise have to read, write, or propagate these values.
It also means decreased memory usage-- not just for sculpt mode
but for any mesh that was in sculpt mode. Previously the mask, face set,
and hide status layers were *always* allocated by sculpt mode.
Here are a few basic tests when masking and face sets are not used:
| Test | Before | After |
| Subsurf Modifier | 148 ms | 126 ms |
| Sculpt Overlay Extraction | 24 ms every redraw | 0 ms |
| Memory usage | 252 MB | 236 MB |
I wouldn't expect any difference when they are used though.
The code changes are mostly just making sculpt features safe for when
the layers aren't stored, and some changes to the conversion to and
from the hide layers. Use of the ".hide_poly" attribute replaces testing
whether face sets are negative in many places.
Differential Revision: https://developer.blender.org/D15937
* Fixed crash in debug draw code. Apparently this is
only used by PBVH draw?
* Debug draw code can now be forcibly enabled in release
mode (i.e. RelWithDebugInfo) by uncommenting a commented
out #define.
* Fixed colors in debug draw mode.
* PBVH node boxes in debug mode now flash a different color
when they are updated.
This commit moves the hide status of mesh vertices, edges, and faces
from the `ME_FLAG` to optional generic boolean attributes. Storing this
data as generic attributes can significantly simplify and improve code,
as described in T95965.
The attributes are called `.hide_vert`, `.hide_edge`, and `.hide_poly`,
using the attribute name semantics discussed in T97452. 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 by default,
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 the hide status is used. When the flags are removed
completely, requirements will decrease when hiding is unused.
Further notes:
* Some code can be further simplified to skip some processing when the
hide attributes don't exist.
* The data is still stored in flags for `BMesh`, necessitating some
complexity in the conversion to and from `Mesh`.
* Access to the "hide" property of mesh elements in RNA is slower.
The separate boolean arrays should be used where possible.
Ref T95965
Differential Revision: https://developer.blender.org/D14685
Mask and color brushes were using the existing PBVH vertex "update tag"
to mark their modifications. This was mostly unnecessary, and causes
unnecessary calculation of normals. It also caused errors though,
because they didn't tag the corresponding PBVH node for normal
recalculation, causing problems on the borders of nodes, since one
node might accumulate into another's vertex normals, but the other
node wouldn't also accumulate and normalize the normals.
The solution is to only use the update tag for tagging deformed
vertices that need recalculated normals. Everything else is handled at
the PBVH node level (which was already the case, but it wasn't clear).
The update tag was also used for undo to tag the nodes corresponding to
changed vertices. This was wrong though, because normals and visibility
would also be recalculated for just color or mask undo steps. Instead,
just use local arrays to map from vertices to nodes.
Differential Revision: https://developer.blender.org/D15581
This is a port of sculpt-dev's `SculptVertRef` refactor
(note that `SculptVertRef was renamed to PBVHVertRef`)
to master. `PBVHVertRef` is a structure that abstracts
the concept of a vertex in the sculpt code; it's simply
an `intptr_t` wrapped in a struct.
For `PBVH_FACES` and `PBVH_GRIDS` this struct stores a
vertex index, but for `BMesh` it stores a direct pointer
to a BMVert. The intptr_t is wrapped in a struct to prevent
the accidental usage of it as an index.
There are many reasons to do this:
* Right now `BMesh` verts are not logical sculpt verts;
to use the sculpt API they must first be converted to indices.
This requires a lot of indirect lookups into tables, leading to performance
loss. It has also led to greater code complexity and duplication.
* Having an abstract vertex type makes it feasible to have one unified
temporary attribute API for all three PBVH modes, which in turn
made it rather trivial to port sculpt brushes to DynTopo in
sculpt-dev (e.g. the layer brush, draw sharp, the smooth brushes,
the paint brushes, etc). This attribute API will be in a future patch.
* We need to do this anyway for the eventual move to C++.
Differential Revision: https://developer.blender.org/D14272
Reviewed By: Brecht Van Lommel
Ref D14272
This patch adds support for PBVH drawing in EEVEE.
Notes:
# PBVH_FACES only. For Multires we'll need an API to get/cache attributes. DynTopo support will be merged in later with sculpt-dev's DynTopo implementation.
# Supports vertex color and UV attributes only; other types can be added fairly easily though.
# Workbench only sends the active vertex color and UV layers to the GPU.
# Added a new draw engine API method, DRW_cdlayer_attr_aliases_add. Please review.
# The vertex format object is now stored in the pbvh.
Reviewed By: Clément Foucault & Brecht Van Lommel & Jeroen Bakker
Differential Revision: https://developer.blender.org/D13897
Ref D13897