The Blur Attribute node mixes values of neighboring elements in meshes and curves.
Currently it supports points, edges and faces on meshes and points on curves.
In theory, support for face corners could be added, but useful semantics are not
obvious yet.
The node calculates a weighted average of each element with its neighbors (based
on curve/mesh topology). The weight of the element itself is always 1, and the weight
of the neighbor elements is controlled by the weight input socket. In the future,
more options for how different elements are weight can be added (e.g. smoothing
groups and selection).
The node can perform multiple blurring iterations to achieve a blurrier result.
Generally, it is better to do multiple iterations in one node instead of using
multiple blur nodes because it has better performance in the current implementation.
We use the term "Blur" (instead of "Smooth") because smoothing is generally more
related to removing roughness from surfaces. When viewing the result of the
Blur Attribute node in the viewport, it looks like an image is blurred. While the
node can also be used to smooth surfaces, other/better algorithms exists for that
purpose (which e.g. don't reduce the volume of the mesh to zero with too many
iterations).
Differential Revision: https://developer.blender.org/D13952
d68c47ff34