"session-wise" here mean while editing a same .blend file. So creating
or opening a new one will reset the uuid counter. This should avoid any
overflow in practice.
Only IDs added to Main database get an uuid, runtime-only ones are not
affected.
This is intended to provide undo with a way to find IDs across several
'memory realms' (undo speedup project).
No behavior change is expected from this commit itself.
Part of T60695.
Differential Revision: https://developer.blender.org/D7007
Introduce new IDTypeInfo structure.
Each ID type will have its own, with some minimal basic common info,
and ID management callbacks.
This patch only does it for Object type, for demo/testing purpose.
Moving all existing IDs is a goal of next "cleanup Friday".
Note that BKE_idcode features should then be merged back into BKE_idtype -
but this will have to be done later, once all ID types have been properly
converted to the new system.
Another later TODO might be to try and add callbacks for file read/write,
and lib_query ID usages looper.
This is part of T73719.
Thanks to @brecht for initial idea, and reviewing the patch.
Differential Revision: https://developer.blender.org/D6966
Instead of using anonymous booleans flags, also allows to keep the same
behavior in all cases, without needing special handling from calling
code for our beloved oddballs object proxies...
Handling those through different ways /might/ be needed sometimes, but
in most case this is just a nest of issues, since you can easily forget
to take them into account.
Note that this should be a 'non-functional' change, as this new behavior
is not used anywhere yet.
Using a struct here allows to change given parameters to the callbacks
without having to edit all callbacks functions, which is always noisy
and time consuming.
Even though we do not have much of those, this might change in the
future, and in any case having specific functions for this ID type in
generic `BKE_lib` area was really confusing.
