The extensions system allows to extend Blender with connectivity to the internet. Right now it means Blender can
discover and install add-ons and themes directly from the internet, and notify users about their updates.
By default this is disabled (opt-in), and users can enable it the first time they try to install an extension or visit
the Prefences > Extensions tab. If this is enabled, Blender will automatically check for updates for
extensions.blender.org upon startup.
When will Blender access the remote repositories:
* Every time you open the Preferences → Extensions: ALL the enabled repositories get checked for the latest info (json)
* Every time you try to install by dragging: ALL the enabled repositories get checked for the latest info (json).
* Every time you start Blender: selected repositories get checked for the latest info (json).
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From the Blender code point of view, this means that most of the add-ons and themes originally bundled with Blender
will now be available from the online platform, instead of bundled with Blender. The exception are add-ons which are
deemed core functionality which just happened to be written as Python add-ons.
Links:
* Original Extenesions Platform Announcement: https://code.blender.org/2022/10/blender-extensions-platform/
* Extensions website: https://extensions.blender.org/
* User Manual: https://docs.blender.org/manual/en/4.2/extensions/index.html#extensions-index
* Technical specifications: https://developer.blender.org/docs/features/extensions/
* Changes on add-ons bundling: https://devtalk.blender.org/t/changes-to-add-on-bundling-4-2-onwards/34593
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This PR does the following:
* Move extensions out of experimental.
* No longer install `scripts/addons` & `scripts/addons_contrib`.
* Add `scripts/addons_core` to blender's repository.
These add-ons will still be bundled with Blender and will be always enabled in the future, with their preferences
moved to be more closely integrated with the rest of Blender. This will happen during the remaining bcon2 period.
For more details, see #121830
From scripts/addons:
* copy_global_transform.py
* hydra_storm
* io_anim_bvh
* io_curve_svg
* io_mesh_uv_layout
* io_scene_fbx
* io_scene_gltf2
* pose_library
* ui_translate
* viewport_vr_preview
Extra: bl_pkg (scripts/addons_contrib)
Note: The STL (legacy) add-on is going to be moved to the extensions platform. There is already a C++ version on core
which is enabled by default.
All the other add-ons are already available at extensions.blender.org. To use them you need to:
* Go to User Preferences > Extensions
* You will be greated with an "Online Extensions" message, click on "Enable Repository".
* Search the add-on you are looking for (e.g, Import Images as Planes).
* Click on Install
Over time their maintaince will be transferred over to the community so their development can carry on. If you used to
help maintain a bundled add-on please read: https://devtalk.blender.org/t/changes-to-add-on-bundling-4-2-onwards/34593
Ref: !121825
c4a0bbb1f4