This greatly simplifies the Point Distribute node. For a poisson disk
distribution, it now uses a simpler dart throwing variant. This results
in a slightly lower quality poisson disk distribution, but it still
fulfills our requirements: have a max density, minimum distance input
and stability while painting the density attribute.
This new implementation has a number of benefits over the old one:
* Much less and more readable code.
* Easier to extend with other distribution algorithms.
* Easier to transfer more attributes to the generated points later on.
* More predictable output when changing the max density and min distance.
* Works in 3d, so no projection on the xy plane is necessary.
This is related to T84640.
Differential Revision: https://developer.blender.org/D10104
This node updates the "rotation" attribute on points.
Multiple ways to specify the rotation are supported.
Differential Revision: https://developer.blender.org/D9883
Ref T83668.
This uses the "id" attribute to randomly pick instances from a collection
for each point.
There is one issue. When the collection is updated (e.g. when an object is
added to it), the nodes modifier is not automatically updated. It seems
like we don't have the infrastructure to support this dependency yet.
The same issue exists in the Boolean modifier and with collision collections.
This should be solved separately soonish.
When "Whole Collection" is disabled, one direct child of the input collection
is instanced at each point. A direct child can be an object or a collection.
Currently, all objects are picked approximately equally often. In the future,
we will provide more control over which point gets which instance.
Differential Revision: https://developer.blender.org/D9884
Ref T82372.
This patch adds two related nodes, a node for separating points
and mesh vertices based on a boolean attribute input, and a node
for creating boolean attributes with comparisons.
See the differential for an example file and video.
Point Separate (T83059)
The output in both geometries is just point data, contained in the mesh
and point cloud components, depending which components had data in the
input geometry. Any points with the mask attribute set to true will be
moved from the first geometry output to the second. This means that
for meshes, all edge and face data will be removed. Any point domain
attributes are moved to the correct output geometry as well.
Attribute Compare (T83057)
The attribute compare does the "Equal" and "Not Equal" operations by
comparing vectors and colors based on their distance from each other.
For other operations, the comparison is between the lengths of the
vector inputs. In general, the highest complexity data type is used
for the operation, and a new function to determine that is added.
Differential Revision: https://developer.blender.org/D9876
This patch does two things:
* Introduce a Seed to the random distribution method
* Bring in a new distribution method for the point scattering node
Patch Review: https://developer.blender.org/D9787
Note: This commit doesn't not handle doversion. Which means that users
need to manually update their files that were using the Point Distribute
node and reconnect inputs to the "Maximum Density" socket.
Original patch by Sebastian Parborg, with changes to not rely on the cy
libraries and overall cleanup.
Patch review by Jacques Lucke, besides help with the new "heap" system
that was required for this algorithm.
Based on Cem Yuksel. 2015. Sample Elimination for Generating Poisson Disk
Sample. Sets. Computer Graphics Forum 34, 2 (May 2015), 25-32
http://www.cemyuksel.com/research/sampleelimination/
This is a non-functional change. The functionality introduced in this commit
is not used in master yet. It is used by nodes that are being developed in
other branches though.
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
