Because the the vertex group name-to-index map is stored in the object
rather than object data, the object info node has to replace the
map when it replaces the mesh component on the geometry set with mesh
data from another object.
This normally works fine as a way to use the vertex groups from the
input mesh, but when passing this mesh to the next modifier, the entire
mesh component was replaced, removing the vertex group name map.
This commit adds a function to replace only the mesh data in mesh
component, uses it in the modifier code, and updates the relevant
comments.
Note that the fact that vertex group names are stored in object data
is a legacy design decision that should be reevaluated at some point.
Differential Revision: https://developer.blender.org/D10256
Use transform matrices instead of loc, rot, scale variables to store instance transforms.
Reviewed By: JacquesLucke
Differential Revision: http://developer.blender.org/D10211
For the most part, this just adds boilerplate code for volume support in geometry nodes:
* Add `VolumeComponent` next to `MeshComponent`, etc.
* Support `VolumeComponent` in depsgraph object iterator.
Furthermore, I added initial volume support in a few nodes:
* The Object Info node outputs an object instance when the input is a volume object
(that will be the same for mesh objects soonish, to avoid copies).
* Support transforming a `VolumeComponent` in the Transform node.
* Support the `VolumeComponent` in Join Geometry nodes, but only when just one of the
inputs has a volume component for now.
Right now, there is no way to create a `VolumeComponent`, because the Object Info node
outputs an object instance. The `VolumeComponent` will be necessary for upcoming nodes,
which will generate volumes on the fly.
Viewport selection does not work correctly with `VolumeComponent`s currently. I don't
know why that is. That can be figured out a bit later, once we can actually create
new volumes in geometry nodes.
Ref T84604.
Differential Revision: https://developer.blender.org/D10147
Instances are created with an "index" parameter used for persistence over
time through animation. Currently the geometry nodes instancer passes
the index in the array for this value, but the arrays created by the
"Point Distribution" node aren't necessarily stable in this way when
the input mesh is deformed. In D9832 we already mostly solved this
problem with an `id` attribute. The solution here is to create instances
with this attribute as well.
It's important to note that deforming the instanced points *after*
distribution will usually be a better solution for this problem. This
solution is likely still important though.
Differential Revision: https://developer.blender.org/D10024
In the report, the geometry is copied because it has two users and the
final join node needs to write to it. The join node also happens to
remove attributes apparently, because it exposed a mistake in the "copy"
method of the `MeshComponent` class. The copy is supposed to be
a deep copy, but the vertex group name map was not duplicated.
Differential Revision: https://developer.blender.org/D9991
The Point Instance node can instance entire collections now.
Before, only individual collections were supported.
Randomly selecting objects from the collection on a per point basis
is not support, yet.
Last part of D9739.
Ref T82372.
This is the initial merge from the geometry-nodes branch.
Nodes:
* Attribute Math
* Boolean
* Edge Split
* Float Compare
* Object Info
* Point Distribute
* Point Instance
* Random Attribute
* Random Float
* Subdivision Surface
* Transform
* Triangulate
It includes the initial evaluation of geometry node groups in the Geometry Nodes modifier.
Notes on the Generic attribute access API
The API adds an indirection for attribute access. That has the following benefits:
* Most code does not have to care about how an attribute is stored internally.
This is mainly necessary, because we have to deal with "legacy" attributes
such as vertex weights and attributes that are embedded into other structs
such as vertex positions.
* When reading from an attribute, we generally don't care what domain the
attribute is stored on. So we want to abstract away the interpolation that
that adapts attributes from one domain to another domain (this is not
actually implemented yet).
Other possible improvements for later iterations include:
* Actually implement interpolation between domains.
* Don't use inheritance for the different attribute types. A single class for read
access and one for write access might be enough, because we know all the ways
in which attributes are stored internally. We don't want more different internal
structures in the future. On the contrary, ideally we can consolidate the different
storage formats in the future to reduce the need for this indirection.
* Remove the need for heap allocations when creating attribute accessors.
It includes commits from:
* Dalai Felinto
* Hans Goudey
* Jacques Lucke
* Léo Depoix
