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
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.
Remove most includes of this header inside other headers, to remove unnecessary
indirect includes which can have a impact on compile times. In the future we may
want more dedicated "_fwd.hh" headers, but until then, this sticks with the
solution in existing code.
Unfortunately it isn't yet possible to remove the include from `BKE_geometry_set.hh`.
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.
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
Curve normal is not available in legacy particle hair system. Construct
a local coordinate system instead of using a fixed normal direction [1,
0, 0] to avoid black appearance.
Implements the paper [A Microfacet-based Hair Scattering
Model](https://onlinelibrary.wiley.com/doi/full/10.1111/cgf.14588) by
Weizhen Huang, Matthias B. Hullin and Johannes Hanika.
### Features:
- This is a far-field model, as opposed to the previous near-field
Principled Hair BSDF model. The hair is expected to be less noisy, but
lower roughness values takes longer to render due to numerical
integration along the hair width. The hair also appears to be flat when
viewed up-close.
- The longitudinal width of the scattering lobe differs along the
azimuth, providing a higher contrast compared to the evenly spread
scattering in the near-field Principled Hair BSDF model. For a more
detailed comparison, please refer to the original paper.
- Supports elliptical cross-sections, adding more realism as human hairs
are usually elliptical. The orientation of the cross-section is aligned
with the curve normal, which can be adjusted using geometry nodes.
Default is minimal twist. During sampling, light rays that hit outside
the hair width will continue propogating as if the material is
transparent.
- There is non-physical modulation factors for the first three
lobes (Reflection, Transmission, Secondary Reflection).
### Missing:
- A good default for cross-section orientation. There was an
attempt (9039f76928) to default the orientation to align with the curve
normal in the mathematical sense, but the stability (when animated) is
unclear and it would be a hassle to generalise to all curve types. After
the model is in main, we could experiment with the geometry nodes team
to see what works the best as a default.
Co-authored-by: Lukas Stockner <lukas.stockner@freenet.de>
Pull Request: https://projects.blender.org/blender/blender/pulls/105600
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 8d0920ec6d and aef0e72e5a.
In a test case with 2 million curves and 15 million points
I observed a 10x performance improvement, from 2.2s to 0.2s
to copy the data from Blender to Cycles.
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
Copy the improved hair curves sync implementation from D14942. That patch is
not ready as a whole but this part was verified to match the old hair particles
can be used already.
These mutable pointers present problems with ownership in relation to
proper copy-on-write for attributes. The simplest solution is to just
remove them and retrieve the layers from `CustomData` when they are
needed. This also removes the complexity and redundancy of having to
update the pointers as the curves change. A similar change will apply
to meshes and point clouds.
One downside of this change is that it makes random access with RNA
slower. However, it's simple to just use the RNA attribute API instead,
which is unaffected. In this patch I updated Cycles to do that. With
the future attribute CoW changes, this generic approach makes sense
because Cycles can just request ownership of the existing arrays.
Differential Revision: https://developer.blender.org/D15486
After becb1530b1 the new curves object type isn't hidden
behind an experimental flag anymore, and other areas depend on this,
so disabling curves at compile time doesn't make sense anymore.
To avoid Cycles not showing any hair by default, and to avoid very slow render
due to many overlaps with the previous 1 meter default in the node.
Fixes T97584, T99319
Differential Revision: https://developer.blender.org/D15405
* Replace license text in headers with SPDX identifiers.
* Remove specific license info from outdated readme.txt, instead leave details
to the source files.
* Add list of SPDX license identifiers used, and corresponding license texts.
* Update copyright dates while we're at it.
Ref D14069, T95597
This adds support for exporting attributes from a Blender Curves object to Cycles.
The implementation follows that of the Mesh object. This also creates motion blur
data if the "velocity" attribute is present on the Curves.
Ref T94193
Reviewed By: brecht
Maniphest Tasks: T94193
Differential Revision: https://developer.blender.org/D14088
Based on discussions from T95355 and T94193, the plan is to use
the name "Curves" to describe the data-block container for multiple
curves. Eventually this will replace the existing "Curve" data-block.
However, it will be a while before the curve data-block can be replaced
so in order to distinguish the two curve types in the UI, "Hair Curves"
will be used, but eventually changed back to "Curves".
This patch renames "hair-related" files, functions, types, and variable
names to this convention. A deep rename is preferred to keep code
consistent and to avoid any "hair" terminology from leaking, since the
new data-block is meant for all curve types, not just hair use cases.
The downside of this naming is that the difference between "Curve"
and "Curves" has become important. That was considered during
design discussons and deemed acceptable, especially given the
non-permanent nature of the somewhat common conflict.
Some points of interest:
- All DNA compatibility is lost, just like rBf59767ff9729.
- I renamed `ID_HA` to `ID_CV` so there is no complete mismatch.
- `hair_curves` is used where necessary to distinguish from the
existing "curves" plural.
- I didn't rename any of the cycles/rendering code function names,
since that is also used by the old hair particle system.
Differential Revision: https://developer.blender.org/D14007
This patch refactors the "Hair" data-block, which will soon be renamed
to "Curves". The larger change is switching from an array of `HairCurve`
to find indices in the points array to simply storing an array of offsets.
Using a single integer instead of two halves the amount of memory for that
particular array.
Besides that, there are some other changes in this patch:
- Split the data-structure to a separate `CurveGeometry`
DNA struct so it is usable for grease pencil too.
- Update naming to be more aligned with newer code and the style guide.
- Add direct access to some arrays in RNA
-- Radius is now retrieved as a regular attribute in Cycles.
-- `HairPoint` has been renamed to `CurvePoint`
-- `HairCurve` has been renamed to `CurveSlice`
- Add comments to the struct in DNA.
The next steps are renaming `Hair` -> `Curves`, and adding support
for other curve types: Bezier, Poly, and NURBS.
Ref T95355
Differential Revision: https://developer.blender.org/D13987
Remove prefix of filenames that is the same as the folder name. This used
to help when #includes were using individual files, but now they are always
relative to the cycles root directory and so the prefixes are redundant.
For patches and branches, git merge and rebase should be able to detect the
renames and move over code to the right file.
