This is part of the short term roadmap goal of simplifying the
compositor workflow
(see https://projects.blender.org/blender/blender/issues/134214).
The problem is that many users don't know how to get started with
compositing in Blender, even when they have used Blender for other
areas, e.g. modeling.
Note: although the solution makes compositor node trees reusable
accross blend files, this is a nice side effect and not the main goal
of the PR.
This PR implements a "New" button that creates a new compositing node
tree, and manages trees as IDs. This has following advantages:
- Consistent with other node editors and other parts of Blender,
therefore making it easier to getting started with compositing if users
are familiar with shading or geometry nodes
- Give users the ability to reuse the compositing node tree by linking
or appending it.
Note: The parameter "Use Nodes" is still present in this PR, but will
be removed (in a backward compatible way) in a follow up PR.
Pull Request: https://projects.blender.org/blender/blender/pulls/135223
bd61e69be5