Implements https://github.com/godotengine/godot-proposals/issues/4096
* Nodes can be marked unique to the scene in the editor (or via code).
* Unique nodes can be accessed via the **%** prefix at any point in the path. From that point in the path (depending on whether the scene of the path is), the unique node will be fetched.
* Implementation is very optimal, as these nodes are cached.
* Instead of containing single animations, AnimationPlayer now contains libraries.
* Libraries, in turn, contain the animations.
This paves the way for implementing the possibility of importing scenes as animation libraries, finally allowing to import animations separate from the 3D models.
Missing (will be done on separate PRs):
* Make it possible to import scenes (dae/fbx/gltf) as animation libraries.
* Make it possible for AnimationTree to import animation libraries on its own, so it does not rely on AnimationPlayer for everything.
The new default project theme uses StyleBoxFlat extensively for
a more modern design and better scalability to multiple resolutions.
SVG icons are now used in place of PNG icons. While this does not
allow for true vector-based icon drawing (icons are still rasterized
at load-time), this makes the design work easier for contributors
and opens the door to vector drawing in the future (e.g. with polygons
or SDFs).
Like for editor icons, the SVG header file is now built automatically
when a SVG file is changed. This removing the need for running
`make_header.py` manually (TODO).
The "Use Hidpi" project setting has been removed in favor of a
"Default Theme Scale" project setting, which allows creating the
default theme at a higher/lower scale than the default.
This can be used when designing GUIs with a high base resolution
to ensure crisp visuals.
Co-authored-by: Yuri Sizov <yuris@humnom.net>
GPUParticles attractors and collision are currently only available in 3D.
Their 2D counterparts haven't been implemented yet, but they will use
separate nodes.
This makes the Linear and Cubic icons in particular easier to
distinguish from each other.
The Cubic interpolation icon's curve was also changed to be
more distinguishable from the Linear icon's curve.
