Blender Git Loki

When using the "new cache library" operator, enable fake user by
default.

Nothing actually links to a cache library at this point (and probably
won't in the future), so fake user is necessary to avoid losing data.

New reader/writer for DerivedMesh.

Used as a base for existing PointCacheModifier classes, but can be used
on its own.

Disabled specialized Point Cache modifier handling in the modifier
stack, this will be replaced and is not correct anyway.

Operator skeleton for a cache bake operator, using the job system.

Deleted unimplemented parts of the previous pointcache system, to make
refactoring simpler.

Since the new approach is not tied to the old set of point cache data
types there is really no need to carry their empty husks around. Once
the new caching system is defined in detail we can add back whatever
makes sense.

Refactoring of archive handling in readers/writers.

Now instead of each reader/writer creating its own archive, the archive
is created by the caller in advance and passed as a constructor
argument. This means that multiple items can be stored together in the
same archive.

General support for export to/import from Alembic files based on Cache
Libraries.

Removed unused Scene pointer from the base Reader/Writer classes.

Fix for undefined return value.

Draw some UI buttons for all the current cache item types.

Make sure cache item pointers are lib-linked correctly.

Unlink and cleanup functions when objects or the cached group get
unlinked or changed.

Removed unused line.

Name string construction for cache items, to use as a unique identifier
in the cache library.

Removed meaningless comment.

Improved collections in RNA for looping over potential caching items
in the object group.

Simple cache manager panel UI in the scene buttons.

This is mostly a simple and unintrusive placeholder to have some way of
making caches accessible, but needs some more thought.

Link main CacheLibrary pointers in readfile.

BKE functions for managing cache content based on a group.

This uses a complete hierarchy of group instances, based on a path
hierarchy (object names).

Putting

Define a collection of "object_caches" in the CacheLibrary RNA for
iterating over all objects eligible for caching in the group.

This allows for nested dupligroup instances as well. All objects that
are instantiated at least once by any group can be included in the
respective cache, but get represented only once because the cached data
is the same anyway.