Currently, there are two attribute API. The first, defined in `BKE_attribute.h` is
accessible from RNA and C code. The second is implemented with `GeometryComponent`
and is only accessible in C++ code. The second is widely used, but only being
accessible through the `GeometrySet` API makes it awkward to use, and even impossible
for types that don't correspond directly to a geometry component like `CurvesGeometry`.
This patch adds a new attribute API, designed to replace the `GeometryComponent`
attribute API now, and to eventually replace or be the basis of the other one.
The basic idea is that there is an `AttributeAccessor` class that allows code to
interact with a set of attributes owned by some geometry. The accessor itself has
no ownership. `AttributeAccessor` is a simple type that can be passed around by
value. That makes it easy to return it from functions and to store it in containers.
For const-correctness, there is also a `MutableAttributeAccessor` that allows
changing individual and can add or remove attributes.
Currently, `AttributeAccessor` is composed of two pointers. The first is a pointer
to the owner of the attribute data. The second is a pointer to a struct with
function pointers, that is similar to a virtual function table. The functions
know how to access attributes on the owner.
The actual attribute access for geometries is still implemented with the `AttributeProvider`
pattern, which makes it easy to support different sources of attributes on a
geometry and simplifies dealing with built-in attributes.
There are different ways to get an attribute accessor for a geometry:
* `GeometryComponent.attributes()`
* `CurvesGeometry.attributes()`
* `bke::mesh_attributes(const Mesh &)`
* `bke::pointcloud_attributes(const PointCloud &)`
All of these also have a `_for_write` variant that returns a `MutabelAttributeAccessor`.
Differential Revision: https://developer.blender.org/D15280
Allow for a small epsilon to improve handling of uvs that are on edges.
Generally, when using reverse uv sampling, we expect that the sampling
is supposed to succeed.
This commit moves the subdivide curve node implementation to the
geometry module, changes it to work on the new curves data-block,
and adds support for Catmull Rom curves. Internally I also added
support for a curve domain selection. That isn't used, but it's
nice to have the option anyway.
Users should notice better performance as well, since we can avoid
many small allocations, and there is no conversion to and from the
old curve type.
The code uses a similar structure to the resample node (60a6fbf5b5)
and the set type node (9e393fc2f1). The resample curves node can be
restructured to be more similar to this soon though.
Differential Revision: https://developer.blender.org/D15334
This refactor had two main goals:
* Simplify the sampling code by using an algorithm with fewer special cases.
* Generalize the sampling to support non-sorted samples.
The `SampleSegmentHint` optimization was inspired by `ValueAccessor` from
OpenVDB and improves performance 2x in my test cases.
Differential Revision: https://developer.blender.org/D15348
In "size" voxel resolution mode, calculating the bounds of the mesh to
volume node's input mesh isn't necessary. For high poly this can take
a few milliseconds, so this commit skips the calculation unless we need
it for the "Amount" mode.
Differential Revision: https://developer.blender.org/D15324
This adds a Mesh To Volume Node T86838 based on the existing modifier.
The mesh to volume conversion is implemented in the geometry module,
and shared between the node and the modifier.
Currently the node outputs a grid with the name "density". This may
change in the future depending on the decisions made in T91668.
The original patch was by Kris (@Metricity), further implementation
by Geramy Loveless (@GeramyLoveless), then finished by Erik Abrahamsson
(@erik85).
Differential Revision: https://developer.blender.org/D10895
This splits out the code that samples points on a surface and the
code that initializes new curves. This code will be reused by D15134.
Differential Revision: https://developer.blender.org/D15216
This commit ports the "Set Spline Type" node to the new curves type.
Performance should be improved in similar ways to the other refactors
from the conversion task (T95443). Converting to and from Catmull Rom
curves is now supported. There are a few cases where a lot of work can
be skipped: when the number of points doesn't change, and when the
types already match the goal type.
The refactor has a few other explicit goals as well:
- Don't count on initialization of attribute arrays when they are
first allocated.
- Avoid copying the entire data-block when possible.
- Make decisions about which attributes to copy when changing curves
more obvious.
- Use higher-level methods to copy data between curve points.
- Optimize for the common cases of single types and full selections.
- Process selected curves of the same types in the same loop.
The Bezier to NURBS conversion is written by Piotr Makal (@pmakal).
Differential Revision: https://developer.blender.org/D14769
This implements the new way to attach curves to a mesh surface using
a uv map (based on the recent discussion in T95776).
The curves data block now not only stores a reference to the surface object
but also a name of a uv map on that object. Having a uv map is optional
for most operations, but it will be required later for animation (when the
curves are supposed to be deformed based on deformation of the surface).
The "Empty Hair" operator in the Add menu sets the uv map name automatically
if possible. It's possible to start working without a uv map and to attach the
curves to a uv map later on. It's also possible to reattach the curves to a new
uv map using the "Curves > Snap to Nearest Surface" operator in curves sculpt
mode.
Note, the implementation to do the reverse lookup from uv to a position on the
surface is trivial and inefficient now. A more efficient data structure will be
implemented separately soon.
Differential Revision: https://developer.blender.org/D15125
This removes the manual construction of a box mesh in the mesh sequence
cache modifier when the Alembic procedural is enabled. It also removes
the use of `BKE_object_boundbox_get` which doesn't make sense on a
non-evaluated object.
Differential Revision: https://developer.blender.org/D14958
This commit adds an option to interpolate the number of control points
in new curves based on the count in neighboring existing curves. The
idea is to provide a more automatic default than manually controlling
the number of points in a curve, so users don't have to think about
the resolution quite as much.
Internally, some utilities for creating new curves are extracted to a
new header file. These can be used for the various nodes and operators
that create new curves.
The top-bar UI will be adjusted in a separate patch, probably moving
all of the settings that affect the size and shape of the new curves
into a popover.
Differential Revision: https://developer.blender.org/D14877
Goals:
* Better high level control over where devirtualization occurs. There is always
a trade-off between performance and compile-time/binary-size.
* Simplify using array devirtualization.
* Better performance for cases where devirtualization wasn't used before.
Many geometry nodes accept fields as inputs. Internally, that means that the
execution functions have to accept so called "virtual arrays" as inputs. Those
can be e.g. actual arrays, just single values, or lazily computed arrays.
Due to these different possible virtual arrays implementations, access to
individual elements is slower than it would be if everything was just a normal
array (access does through a virtual function call). For more complex execution
functions, this overhead does not matter, but for small functions (like a simple
addition) it very much does. The virtual function call also prevents the compiler
from doing some optimizations (e.g. loop unrolling and inserting simd instructions).
The solution is to "devirtualize" the virtual arrays for small functions where the
overhead is measurable. Essentially, the function is generated many times with
different array types as input. Then there is a run-time dispatch that calls the
best implementation. We have been doing devirtualization in e.g. math nodes
for a long time already. This patch just generalizes the concept and makes it
easier to control. It also makes it easier to investigate the different trade-offs
when it comes to devirtualization.
Nodes that we've optimized using devirtualization before didn't get a speedup.
However, a couple of nodes are using devirtualization now, that didn't before.
Those got a 2-4x speedup in common cases.
* Map Range
* Random Value
* Switch
* Combine XYZ
Differential Revision: https://developer.blender.org/D14628
Remembering the number of curves of every type makes it fast to know
whether processing specific to a single curve type has to be done.
This information was accessed in quite a few places, so this should be
an overall reduction in overhead for the new curves type.
The cache is computed eagerly, in other words every time after changing
the curve types. In order to reduce verbosity I added helper functions
for some common ways to set the types.
Differential Revision: https://developer.blender.org/D14732
This is mostly a cleanup to avoid hardcoding the eager calculation of
normals it isn't necessary, by reducing calls to `BKE_mesh_calc_normals`
and by removing calls to `BKE_mesh_normals_tag_dirty` when the mesh
is newly created and already has dirty normals anyway. This reduces
boilerplate code and makes the "dirty by default" state more clear.
Any regressions from this commit should be easy to fix, though the
lazy calculation is solid enough that none are expected.
If the `wpoly` vector was small, the `wpoly_new` pointer could point
to part of its inline buffer on the stack, which becomes invalid out of
that scope. Instead, store `wpoly_new` as a span, and assign it properly
from the moved vector.
If all islands had a size of zero, a division by zero would occur in
`GEO_uv_parametrizer_pack`, causing the UV coordinates to be set to
NaN. An alternative approach would be to skip packing islands with a
zero size, but If UV coordinates are for example outside the 0-1 range,
it's better if they get moved into that range.
Differential Revision: https://developer.blender.org/D14522
Add "for_write" on function names that retrieve mutable data arrays.
Though this makes function names longer, it's likely worth it because
it allows more easily using the const functions in a non-const context,
and reduces cases of mistakenly retrieving with edit access.
In the long term, this situation might change more if we implement
attributes storage that is accessible directly on `CurvesGeometry`
without duplicating the attribute API on geometry components,
which is currently the rough plan.
Differential Revision: https://developer.blender.org/D14562
