The evaluated mesh is a result of evaluated modifiers, and referencing
other evaluated IDs such as materials.
It can not be stored in the EditMesh structure which is intended to be
re-used by many areas. Such sharing was causing ownership errors causing
bugs like
T93855: Cycles crash with edit mode and simultaneous viewport and final render
The proposed solution is to store the evaluated edit mesh and its cage in
the object's runtime field. The motivation goes as following:
- It allows to avoid ownership problems like the ones in the linked report.
- Object level is chosen over mesh level is because the evaluated mesh
is affected by modifiers, which are on the object level.
This patch allows to have modifier stack of an object which shares mesh with
an object which is in edit mode to be properly taken into account (before
the change the modifier stack from the active object will be used for all
objects which share the mesh).
There is a change in the way how copy-on-write is handled in the edit mode to
allow proper state update when changing active scene (or having two windows
with different scenes). Previously, the copt-on-write would have been ignored
by skipping tagging CoW component. Now it is ignored from within the CoW
operation callback. This allows to update edit pointers for objects which are
not from the current depsgraph and where the edit_mesh was never assigned in
the case when the depsgraph was evaluated prior the active depsgraph.
There is no user level changes changes expected with the CoW handling changes:
should not affect on neither performance, nor memory consumption.
Tested scenarios:
- Various modifiers configurations of objects sharing mesh and be part of the
same scene.
- Steps from the reports: T93855, T82952, T77359
This also fixes T76609, T72733 and perhaps other reports.
Differential Revision: https://developer.blender.org/D13824
- Add BM_mesh_debug_print & BM_mesh_debug_info.
- Report flags in Mesh.cd_flag in BKE_mesh_debug_print
- Move custom data printing into customdata.cc (noted as a TODO).
Note that the term "runtime" has been removed from
`BKE_mesh_runtime_debug_print` since these are useful for debugging any
kind of mesh data.
As described in T91186, this commit moves mesh vertex normals into a
contiguous array of float vectors in a custom data layer, how face
normals are currently stored.
The main interface is documented in `BKE_mesh.h`. Vertex and face
normals are now calculated on-demand and cached, retrieved with an
"ensure" function. Since the logical state of a mesh is now "has
normals when necessary", they can be retrieved from a `const` mesh.
The goal is to use on-demand calculation for all derived data, but
leave room for eager calculation for performance purposes (modifier
evaluation is threaded, but viewport data generation is not).
**Benefits**
This moves us closer to a SoA approach rather than the current AoS
paradigm. Accessing a contiguous `float3` is much more efficient than
retrieving data from a larger struct. The memory requirements for
accessing only normals or vertex locations are smaller, and at the
cost of more memory usage for just normals, they now don't have to
be converted between float and short, which also simplifies code
In the future, the remaining items can be removed from `MVert`,
leaving only `float3`, which has similar benefits (see T93602).
Removing the combination of derived and original data makes it
conceptually simpler to only calculate normals when necessary.
This is especially important now that we have more opportunities
for temporary meshes in geometry nodes.
**Performance**
In addition to the theoretical future performance improvements by
making `MVert == float3`, I've done some basic performance testing
on this patch directly. The data is fairly rough, but it gives an idea
about where things stand generally.
- Mesh line primitive 4m Verts: 1.16x faster (36 -> 31 ms),
showing that accessing just `MVert` is now more efficient.
- Spring Splash Screen: 1.03-1.06 -> 1.06-1.11 FPS, a very slight
change that at least shows there is no regression.
- Sprite Fright Snail Smoosh: 3.30-3.40 -> 3.42-3.50 FPS, a small
but observable speedup.
- Set Position Node with Scaled Normal: 1.36x faster (53 -> 39 ms),
shows that using normals in geometry nodes is faster.
- Normal Calculation 1.6m Vert Cube: 1.19x faster (25 -> 21 ms),
shows that calculating normals is slightly faster now.
- File Size of 1.6m Vert Cube: 1.03x smaller (214.7 -> 208.4 MB),
Normals are not saved in files, which can help with large meshes.
As for memory usage, it may be slightly more in some cases, but
I didn't observe any difference in the production files I tested.
**Tests**
Some modifiers and cycles test results need to be updated with this
commit, for two reasons:
- The subdivision surface modifier is not responsible for calculating
normals anymore. In master, the modifier creates different normals
than the result of the `Mesh` normal calculation, so this is a bug
fix.
- There are small differences in the results of some modifiers that
use normals because they are not converted to and from `short`
anymore.
**Future improvements**
- Remove `ModifierTypeInfo::dependsOnNormals`. Code in each modifier
already retrieves normals if they are needed anyway.
- Copy normals as part of a better CoW system for attributes.
- Make more areas use lazy instead of eager normal calculation.
- Remove `BKE_mesh_normals_tag_dirty` in more places since that is
now the default state of a new mesh.
- Possibly apply a similar change to derived face corner normals.
Differential Revision: https://developer.blender.org/D12770
Most of the fields in Mesh had no comments, or outdated misleading
comments. For example, "BMESH ONLY" referred to the BMesh project,
not the data structure. Given how much these structs are used, it should
save a lot of time to have proper comments.
I also rearranged the fields in mesh to have a more logical order. Now
the most important fields come first. In the process I was able to
remove 19 bytes of unnecessary padding (31->12). I just had to
change a `short` flag to `char`.
Differential Revision: https://developer.blender.org/D13454
- Added space below non doc-string comments to make it clear
these aren't comments for the symbols directly below them.
- Use doxy sections for some headers.
- Minor improvements to doc-strings.
Ref T92709
When enabling or disabling a Mesh Sequence Cache modifier of an Object
with a hair particle system, the hair would switch positions. This is
caused because original coordinates in Blender are expected to be
normalized, and toggling the modifier would cause the usage of different
orco layers: one that is normalized, and the other which isn't.
This bug exposes a few related issues:
- if the Alembic file did not have orco data,
`MOD_deform_mesh_eval_get`, used by the particle system modifier, would
add an orco layer without normalization
- `MOD_deform_mesh_eval_get` would also ignore the presence of an orco
layer (e.g. one that could have been read from Alembic)
- if the Alembic file did have orco data, the data would be read
unnormalized
To fix those various issues, original coordinates are normalized when
read from Alembic and unnormalized when written to Alembic; and a new
utility function `BKE_mesh_orco_ensure` is added to add a normalized
orco layer if none exists on the mesh already, this function derives
from the code used in the particle system.
Reviewed By: brecht
Maniphest Tasks: T92561
Differential Revision: https://developer.blender.org/D13306
This supported calculating normals for MPoly array which was copied to
an MFace aligned array.
Remove the functions entirely since MFace use is being phased out and
these function isn't used anywhere.
Remove the 'only_face_normals' argument.
- BKE_mesh_calc_normals_poly for polygon normals.
- BKE_mesh_calc_normals_poly_and_vertex for poly and vertex normals.
Order arguments logically:
- Pair array and length arguments.
- Position normal array arguments (to be filled) last.
Because mesh vertex and face normals are just derived data, they can
be calculated lazily instead of eagerly. Often normal calculation is
a relatively expensive task, and the calculation is often redundant
if the mesh is deformed afterwards anyway.
Instead, normals should be calculated only when they are needed. This
commit moves in that direction by adding a new function to tag a mesh's
normals dirty and replacing normal calculation with it in some places.
Differential Revision: https://developer.blender.org/D12107
Supported multi-threading for bm_mesh_loops_calc_normals.
This is done by operating on vertex-loops instead of face-loops.
Single threaded operation still loops over faces since iterating
over vertices adds some overhead in the case of custom-normals
as the order used for accessing loops must be the same as iterating
of a faces loops.
From isolated timing tests of bm_mesh_loops_calc_normals on high
poly models, this gives between 3.5x to 10x speedup,
with larger gains for meshes with custom-normals.
NOTE: this is part one of two patches for multi-threaded auto-smooth,
tagging edges as sharp is still single threaded.
Reviewed By: mont29
Ref D11928
Also use `const Curve *` instead of `const Object *`, since the
function works at a lower level than objects anyway.
And also remove another unused function. Since this section of code
for converting curves to meshes will likely be replaced, it's nicer to
see which parts actually remain used at this point.
Normals now includes many functions including normal splitting &
custom normal manipulation split this into it's own file
to centralize related functions.
- Multi-thread BKE_mesh_recalc_looptri.
- Add BKE_mesh_recalc_looptri_with_normals,
this skips having to calculate normals for ngons.
Exact performance depends on number of faces, size of ngons and
available CPU cores.
For high poly meshes the isolated improvement to BKE_mesh_recalc_looptri
in my tests was between 6.7x .. 25.0x, with the largest gains seen in
meshes containing ngons with many sides.
The overall speedup for high poly meshes containing quads and triangles
is only ~20% although ngon heavy meshes can be much faster.
This matches BMesh which also has tessellation in it's own file.
Using a separate file helps with organization when
extracting code into smaller functions.
- BKE_mesh_copy_parameters_for_eval to be used for evaluated meshes only
as it doesn't handle ID user-counts.
- BKE_mesh_copy_parameters is a general function for copying parameters
between meshes.
Required changes to make it compile with clang tidy:
* Use c++ includes like (e.g. climits instead limits.h).
* Insert type casts when casting from void* to something else.
* Replace NULL with nullptr.
* Insert casts from int to enum.
* Replace designed initializers (not supported in C++ yet).
* Use blender::Vector instead of BLI_array_staticdeclare (does not compile with C++).
* Replace typedef statements.
Ref T83357.
When using Optimal Display, some edges are not flagged `ME_EDGEDRAW` |
`ME_EDGERENDER`.
When the modifier is applied through the UI in the modifier stack this is
not an issue because the `modifyMesh` callback is run with
`MOD_APPLY_TO_BASE_MESH` (this will effectively turn of Optimal
Display).
When converting to mesh though, this will just get an evaluated mesh
(where the edge flags are still the same as with the subdivision
modifier).
Now ensure every edge is flagged to draw after conversion.
Maniphest Tasks: T81997
Differential Revision: https://developer.blender.org/D9331
This modifier is the opposite of the recently added Mesh to Volume modifier.
It converts the "surface" of a volume into a mesh. The "surface" is defined
by a threshold value. All voxels with a density higher than the threshold
are considered to be inside the volume, while all others will be outside.
By default, the resolution of the generated mesh depends on the voxel
size of the volume grid. The resolution can be customized. It should be
noted that a lower resolution might not make this modifier faster. This
is because we have to downsample the openvdb grid, which isn't a cheap
operation.
Converting a mesh to a volume and then back to a mesh is possible,
but it does require two separate mesh objects for now.
Reviewers: brecht
Differential Revision: https://developer.blender.org/D9141
`BKE_mesh_calc_edges` was the main performance bottleneck in D9141.
While openvdb only needed ~115ms, calculating the edges afterwards
took ~960ms. Now with some parallelization this is reduced to ~210ms.
Parallelizing `BKE_mesh_calc_edges` is not entirely trivial, because it
has to perform deduplication and some other things that have to happen
in a certain order. Even though the multithreading improves performance
with more threads, there are diminishing returns when too many threads
are used in this function.
The speedup is mainly achieved by having multiple hash tables that are
filled in parallel. The distribution of the edges to hash tables is based on
a hash (that is different from the hash used in the actual hash tables).
I moved the function to C++, because that made it easier for me to
optimize it. Furthermore, I added `BLI_task.hh` which contains some
light tbb wrappers for parallelization.
Reviewers: campbellbarton
Differential Revision: https://developer.blender.org/D9151
Those were only shallow wrappers around `BKE_id_copy`, barely used (even
fully unused in some cases), and we want to get rid of those ID-specific
helpers for the common ID management tasks. Also prevents weird custom
behaviors (like `BKE_object_copy`, who was the only basic ID copy
function to reset user count of the new copy to zero).
Part of 71219.
Just converts verts to points and vice versa.
Materials and Attribute layers are preserved (so for example if you set
custom radii on the pointcloud, convert to mesh, then convert back to
pointcloud, this will be preserved).
Also not add a Radius layer by default (it is still added and
filled when adding a pointcloud object from the menu), a global Radius
property that will be used if there is no radius attribute can be added
later. A Radius attribute can also be added in the pointcloud data
properties (and filled via python).
This will also add a new utility function that copies materials between
datablocks: BKE_id_materials_copy
ref T75717
Differential Revision: https://developer.blender.org/D7391
This replaces header include guards with `#pragma once`.
A couple of include guards are not removed yet (e.g. `__RNA_TYPES_H__`),
because they are used in other places.
This patch has been generated by P1561 followed by `make format`.
Differential Revision: https://developer.blender.org/D8466
