With the asset identifier introduced in the previous commit, we can now
locate an asset just from its `AssetRepresentation`, without requiring
information from the asset library and the file browser storage. With
this we can remove some hacks and function parameters. A RNA/BPY
function is also affected, but I didn't remove the paramter to keep
compatibility. It's simply ignored and not required anymore, noted this
in the parameter description (noted for T102877).
Introduces a new `AssetRepresentation` type, as a runtime only container
to hold asset information. It is supposed to become _the_ main way to
represent and refer to assets in the asset system, see T87235. It can
store things like the asset name, asset traits, preview and other asset
metadata.
Technical documentation:
https://wiki.blender.org/wiki/Source/Architecture/Asset_System/Back_End#Asset_Representation.
By introducing a proper asset representation type, we do an important
step away from the previous, non-optimal representation of assets as
files in the file browser backend, and towards the asset system as
backend. It should replace the temporary & hacky `AssetHandle` design in
the near future. Note that the loading of asset data still happens
through the file browser backend, check the linked to Wiki page for more
information on that.
As a side-effect, asset metadata isn't stored in file browser file
entries when browsing with link/append anymore. Don't think this was
ever used, but scripts may have accessed this. Can be brought back if
there's a need for it.
Adds the possibility of having a little number on top of icons.
At the moment this is used for:
* Outliner
* Node Editor bread-crumb
* Node Group node header
For the outliner there is almost no functional change. It is mostly a refactor
to handle the indicators as part of the icon shader instead of the outliner
draw code. (note that this was already recently changed in a5d3b648e3).
The difference is that now we use rounded border rectangle instead of
circles, and we can go up to 999 elements.
So for the outliner this shows the number of collapsed elements of a
certain type (e.g., mesh objects inside a collapsed collection).
For the node editors is being used to show the use count for the data-block.
This is important for the node editor, so users know whether the node-group
they are editing (or are about to edit) is used elsewhere. This is
particularly important when the Node Options are hidden, which is the
default for node groups appended from the asset libraries.
---
Note: This can be easily enabled for ID templates which can then be part
of T84669. It just need to call UI_but_icon_indicator_number_set in the
function template_add_button_search_menu.
---
Special thanks Clément Foucault for the help figuring out the shader,
Julian Eisel for the help navigating the UI code, and Pablo Vazquez for
the collaboration in this design solution.
For images showing the result check the Differential Revision.
Differential Revision: https://developer.blender.org/D16284
This is the conventional way of dealing with unused arguments in C++,
since it works on all compilers.
Regex find and replace: `UNUSED\((\w+)\)` -> `/*$1*/`
