Operators did not suffer from this problem as they were still just using notifiers
directly. The "proper" fix is to use the new message bus system. But, we've
got enough problems dealing with COW already as it is now... moving on.
The transform code needed to use data from the "_eval" copy of the posebone
instead of the main-db version, otherwise the initial/reset value would be
wrong, causing the jumping.
Without the exception, adding new poses to pose libraries took several seconds
with only <= 4 bones selected. While we may still need this for other cases too,
since bones are such a common use case, it makes sense to provide some level
of optimisation for them.
This now works by getting the RNA Path from the given PointerRNA to go from the
ID block to the data it points to, then uses this path to find the new data
relative to the COW ID.
Note: This currently still has all the debug prints left in - As can be seen,
I was testing this against the earlier PoseBone hack/special case. We may still
need to bring such special cases back in future, since looking up RNA Paths
like this can be slow.
When using copy on write, insert keyframe operators were reading from old
bmain data instead of COW data. This meant that inserting keyframes would
often read old/stale data, resulting in invalid keyframes getting created
(e.g. from last transform operation, instead of actual current state).
This commit makes it so that keyframing operators will ask depsgraph for
the evaluated copy of the data, so that it can read values from that. It
introduces a new function - `DEG_get_evaluated_rna_pointer()`, which when
working correctly/fully, should work just like the other `DEG_get_evaluated_*()`
functions, except it lets you pass in an RNA Pointer.
However, currently, this is only done for Pose Bones (as a dirty hack, since this
is an important/pivotal requirement for production) and/or datablock
properties directly (since we can just use the DEG_get_evaluated_id() directly).
on the datablock.
Committing to a branch for now as this all needs more testing. More work to come
later at a more sane time of day!
Experimental support for using popovers like menus,
use this when the user hold the mouse down
(previously this did nothing).
This means turning frequently accessed menu items into
popovers doesn't add more clicks to the existing use case.
There are still probably other massive problems to solve (i.e. which copies
of data cache/sim gets written/read from for COW eval) that need to be solved
before we can get the sims actually running though.
OVERVIEW
* In 2.7 terminology, all layers and groups are now collection datablocks.
* These collections are nestable, linkable, instanceable, overrideable, ..
which opens up new ways to set up scenes and link + override data.
* Viewport/render visibility and selectability are now a part of the collection
and shared across all view layers and linkable.
* View layers define which subset of the scene collection hierarchy is excluded
for each. For many workflows one view layer can be used, these are more of an
advanced feature now.
OUTLINER
* The outliner now has a "View Layer" display mode instead of "Collections",
which can display the collections and/or objects in the view layer.
* In this display mode, collections can be excluded with the right click menu.
These will then be greyed out and their objects will be excluded.
* To view collections not linked to any scene, the "Blender File" display mode
can be used, with the new filtering option to just see Colleciton datablocks.
* The outliner right click menus for collections and objects were reorganized.
* Drag and drop still needs to be improved. Like before, dragging the icon or
text gives different results, we'll unify this later.
LINKING AND OVERRIDES
* Collections can now be linked into the scene without creating an instance,
with the link/append operator or from the collections view in the outliner.
* Collections can get static overrides with the right click menu in the outliner,
but this is rather unreliable and not clearly communicated at the moment.
* We still need to improve the make override operator to turn collection instances
into collections with overrides directly in the scene.
PERFORMANCE
* We tried to make performance not worse than before and improve it in some
cases. The main thing that's still a bit slower is multiple scenes, we have to
change the layer syncing to only updated affected scenes.
* Collections keep a list of their parent collections for faster incremental
updates in syncing and caching.
* View layer bases are now in a object -> base hash to avoid quadratic time
lookups internally and in API functions like visible_get().
VERSIONING
* Compatibility with 2.7 files should be improved due to the new visibility
controls. Of course users may not want to set up their scenes differently
now to avoid having separate layers and groups.
* Compatibility with 2.8 is mostly there, and was tested on Eevee demo and Hero
files. There's a few things which are know to be not quite compatible, like
nested layer collections inside groups.
* The versioning code for 2.8 files is quite complicated, and isolated behind
#ifdef so it can be removed at the end of the release cycle.
KNOWN ISSUES
* The G-key group operators in the 3D viewport were left mostly as is, they
need to be modified still to fit better.
* Same for the groups panel in the object properties. This needs to be updated
still, or perhaps replaced by something better.
* Collections must all have a unique name. Less restrictive namespacing is to
be done later, we'll have to see how important this is as all objects within
the collections must also have a unique name anyway.
* Full scene copy and delete scene are exactly doing the right thing yet.
Differential Revision: https://developer.blender.org/D3383https://code.blender.org/2018/05/collections-and-groups/
Without this we need to have the context to get the
(space_type, mode) args for an active tool lookup.
For event handling & poll its more convenient to have direct access.
