Blender Git Loki

Free readers properly after applying cached data.

Set reader/writer archive as a separate step outside the constructors.

This allows nicer creation of readers/writers //before// actually
opening the archive. This in turns can simplify code quite a bit.

Moved functions for constructing readers/writers based on cache library
out of pointcache into blenkernel.

This is quite simple and repetitive and there is not need to have this
in the main pointcache/Alembic API. The code is mostly concerned with
logic of DNA data, so pointcache shouldn't have to deal with it.

Ported archive filename constructor from pointcache library to BKE.

The pointcache library is now pretty much independent from ID blocks and
should not be responsible for handling file paths. The path construction
is also fairly straightforward now compared to the old point cache
system, with only basic conversion of relative to absolute paths for
loading archive files.

Cache read result enum in DNA mirroring the internal pointcache results.

This can be stored in cache library items as an indicator of cache
reading state.

Use a uiTemplate function for showing cache library items instead of
python code to unify symbols.

This is necessary because the operator for adding new items (as opposed
to the enable/disable button) cannot be shown with the same checkbox
button. The UI template function can display a custom button for the
operator, so the look becomes less confusing.

Merge branch 'gooseberry' into temp_motionpaths

Merge branch 'master' into gooseberry

Merge branch 'master' into temp-ghash-experiments

Merge branch 'master' into temp-ghash-experiments

Grrr, thought I had added that file already!

GHash: Add difference and symmetric_difference (with tests).

Also fix some issues in previous commits.

Notes about our 'symmetric_difference':
* name is taken from py, but our function takes multiple arguments,
and returns keys which are present in one and only one given ghash.
So we may want a better name for that
(real symmetric difference only accepts/works with two args)!
* Its code is a bit more complex than the others, think it's worth it though,
XOR is a really useful operation imho.

Enable motion curve update for armatures as well.

This is currently brute force updating, also disabled object copies
but it's likely that we'll need those to do threaded update of the
motionpaths.

Nicer default filename for cache library paths.

This now appends a default extension based on the cache backend used.
At this point this is always Alembic (.abc) but would allow other
backend formats in the future.

Motion Paths real time update WIP

GHash: add intersection (with tests).

GHash: add Union operations (with tests).

Improved filtering for cache library content.

In addition to the object name filtering, items in cache library groups
can now be filtered by type as well.

Existing items in the cache are always displayed, so as to not hide
important information (what gets stored in the cache). The filtering
is primarily a utility to simplify searching inside the group for things
that should be added to the cache.

Use a generator in the python code to iterate over all the potential
cache library items.

This should ideally happen on the RNA side, but making the equivalent of
python generators in the RNA is really difficult.

Don't show mesh cache items for non-mesh objects.