These functions help you reuse materials, objects and other data-blocks loaded from another blend-file. You can build libraries of common content and share them across multiple referencing files.
Library Reload & Relocate¶
From the context menu of the library items in the Outliner's Blender File view, you can reload and relocate a whole library.
Reloading is useful if you changed something in the library blend-file and want to see those changes in your current blend-file without having to re-open it.
Relocating allows you to reload the library from a new file path. This can be used to either fix a broken linked library (e.g. because the library file was moved or renamed after linking from it), or to switch between different variations of a same set of data, in different library files.
While loading a blend-file, if Blender cannot find a library, it will create placeholder data-blocks to replace missing linked ones. That way, references to the missing data is not lost, and by relocating the missing library, the lost data can be automatically restored.
Makes the selected or all external objects local to the current blend-file. Links to the original library file will be lost, but it will make those data-blocks fully editable, just like the ones directly created in that blend-file.
The operation available from the Outliner's context menu has no options, and only affects the selected data-block.
The operation available from the 3D View only directly affects selected objects, but it can also make local the objects' dependencies:
Optionally unlinks the object's Object Data and Material Data.
Selected Objects, + Object Data, + Materials, All (i.e. including all scenes)
For the most part linking data will work as expected, however, there are some corner cases which are not supported.
In general, dependencies should not go in both directions. Attempting to link or append data which links back to the current file will likely result in missing links.
Object Rigid Body Constraints¶
When linking objects directly into a blend-file, the Rigid Body settings will not be linked in since they are associated with their scene's world. As an alternative, you could link in the entire scene and set it as a Background Set.
Compression & Memory Use¶
Linking to blend files with compression enabled may significantly increase memory usage while loading files.
Reading data on demand isn't supported with compression (this only impacts load time, once loaded there is no difference in memory use).