In fact, it was the whole remapping process that was broken in logic bricks area,
due to terrible design of links between those bricks...
Object copying was also broken in that case, fixed as well.
To be backported to 2.78.
Note that issue was actually probably there since ages, hidden behind dirty hacks
used in previous append code (though likely visible in some corner cases).
Listen kids: do not, never, ever, do what has been done for links between logic bricks. Never. Ever.
Even as pure runtime data it would have been bad, but as stored data...
Regression caused by rBb27ba26, we would always tag datablocks to update in G.main,
ignoring given bmain, now always use this one instead.
To be backported to 2.78.
Own fault in new ID management work, thought rebuild the DAG itself was
enough to actually update whole scene, but we actually need to tag datablocks
for update as well, when we change (or remove) one of their ID pointers...
All in all, this patch adds an Alembic importer, an Alembic exporter,
and a new CacheFile data block which, for now, wraps around an Alembic
archive. This data block is made available through a new modifier ("Mesh
Sequence Cache") as well as a new constraint ("Transform Cache") to
somewhat properly support respectively geometric and transformation data
streaming from alembic caches.
A more in-depth documentation is to be found on the wiki, as well as a
guide to compile alembic: https://wiki.blender.org/index.php/
User:Kevindietrich/AlembicBasicIo.
Many thanks to everyone involved in this little project, and huge shout
out to "cgstrive" for the thorough testings with Maya, 3ds Max, Houdini
and Realflow as well as @fjuhec, @jensverwiebe and @jasperge for the
custom builds and compile fixes.
Reviewers: sergey, campbellbarton, mont29
Reviewed By: sergey, campbellbarton, mont29
Differential Revision: https://developer.blender.org/D2060
Those bone pointers in object's pose bite again - turns out they can be accessed
before pose actually gets rebuilt in some cases (e.g. from undo writefile), so
we need to clear the pointers immediately.
libquery now passes an extra flag info to the callback, in case that specific
ID usage is considered as indirect.
In most cases, it's just set from ID_IS_LINKED_DATABLOCK() result on datablock owner,
but in proxy object case we also consider ob->data, materials and pose usages as indirect.
Does not fixes all issues yet, but should already make behavior with proxy object saner.
Main issue was that BKE_libblock_relink_ex was pretty much ignoring all those...
Also, unlinking of objects was not handling correctly indirect-related flags.
Refactored code into helper functions to avoid too much duplicated code.
This is in fact very hairy situation here... Objects are only refcounted by scenes,
any other usage is 'free', which means once all object instanciations are gone Blender
considers it can delete it.
There is a trap here though: indirect usages. Typically, we should never modify linked data
(because it is essencially useless, changes would be ignored and ost on next reload or
even undo/redo). This means indirect usages are not affected by default 'safe' remapping/unlinking.
For unlinking preceeding deletion however, this is not acceptable - we are likely to end with
a zero-user ID (aka deletable one) which is still actually used by other linked data.
Solution choosen here is double:
I) From 'user-space' (i.e. outliner, operators...), we check for cases where deleting datablocks
should not be allowed (indirect data or indirectly used data), and abort (with report) if needed.
II) From 'lower' level (BKE_library_remap and RNA), we also unlink from linked data,
which makes actual deletion possible and safe.
Note that with previous behavior (2.77 one), linked object would be deleted, including from linked data -
but then, once file is saved and reloaded, indirect usage would link back the deleted object,
without any instanciation in scene, which made it somehow virtual and unreachable...
With new behavior, this is no more possible, but on the other hand it means that in situations of dependency cycles
(two linked objects using each other), linked objects become impossible to delete (from user space).
Not sure what's best here, behavior with those corner cases of library linking is very poorly defined... :(
Remapping indirect usage of IDs is forbidden from user space, this is calling for
nice nightmare with libraries handling (and undo crash, among other things).
Not sure why I was 'laxist' about indirect usage cases detection like that,
for now just consider any ID used by another linked datablock as indirect usage case!
Also, added some error/warning reports to Outliner's remap code.
This commit changes a lot of how IDs are handled internally, especially the unlinking/freeing
processes. So far, this was very fuzy, to summarize cleanly deleting or replacing a datablock
was pretty much impossible, except for a few special cases.
Also, unlinking was handled by each datatype, in a rather messy and prone-to-errors way (quite
a few ID usages were missed or wrongly handled that way).
One of the main goal of id-remap branch was to cleanup this, and fatorize ID links handling
by using library_query utils to allow generic handling of those, which is now the case
(now, generic ID links handling is only "knwon" from readfile.c and library_query.c).
This commit also adds backends to allow live replacement and deletion of datablocks in Blender
(so-called 'remapping' process, where we replace all usages of a given ID pointer by a new one,
or NULL one in case of unlinking).
This will allow nice new features, like ability to easily reload or relocate libraries, real immediate
deletion of datablocks in blender, replacement of one datablock by another, etc.
Some of those are for next commits.
A word of warning: this commit is highly risky, because it affects potentially a lot in Blender core.
Though it was tested rather deeply, being totally impossible to check all possible ID usage cases,
it's likely there are some remaining issues and bugs in new code... Please report them! ;)
Review task: D2027 (https://developer.blender.org/D2027).
Reviewed by campbellbarton, thanks a bunch.
