To find all effectors in the scene, we need to loop over all objects.
Doing this during depsgraph evaluation caused crashes because not all
objects are guaranteed to be evaluated yet.
To fix this, we now cache the relations as part of the dependency graph
build. As a bonus this also makes evaluation faster for big scenes,
since looping over all objects for each particle system is slow.
Fixes T55156.
Transform evaluation does depend on that matrix, but relation was never
in dependency graph. It was not even in the old dependency graph, which
makes me wonder how this thing worked reliably to begin with.
Should fix flickering issue in the render farm.
Transform evaluation doesn't not depend on objects which are being duplicated,
so should not be any regressions here.
The whole relation should probably be gone as it's kind of rooting back to
legacy times, but that would need more clear research and investigation and
regression testing.
Note this is now separate from H key hiding, and meant for more persistent
ways to define which objects are relevant to the viewport or render.
This avoids some cases where you'd have to create collection specifically
to hide objects for viewport/render.
This makes evaluated objects to point to a non-evaluated collection,
which is already really bad. What is even more worse, objects in those
collections are not evaluated either.
Proper solution would be to implement visibility flag for nodes, which
will be set to 0 for transform/geometry components, but which will be
1 for copy-on-write components.
This way we will guarantee consistency of dependency graph.
For now this change is good enough and unlocks production.
Fixes T55375: Crash when changing visibility of instanced collection
Fixes T55357: Particle geometry crash
This is a beginning of series of commits which will clearly separate
building IDs which are used as object data from object building.
The goal is to be able to always build whatever ID. Required to make
driver targets to work reliably with copy-on-write concept.
DATA datablock must evaluation must never depend on object it is
used for. If there is something what depends on an object, it must
be done on object level.
At least the actual callback was empty.
Make it more reliable and predictable way of getting pointer to
an original mesh which came from copy-on-write engine.
Related change: made it (hopefully) more clear name for flags.
This includes:
- Skip OB_RECALC_TIME tag from object duplicate operator
not sure why it is needed: even if original object was
animated, duplicating it will copy evaluated values.
- Don't tag whole ID for update when updating it after
relations rebuilt. Use the same trickery to detect
whether animation is to be re-evaluated or not as is
done for update flag=0.
- Don't tag datablocks which are expanded for update
of copy-on-write.
- Avoid flush along relation from copy-on-write
operation in action. This will not invalidate any
pointers in the copied datablock since we don't
reference anything in the action.
After discussion with Sergey and Dalai, we have decided to remove
this option completely. We're getting to the point where it is almost
impossible to really use 2.8 without COW, and keeping the old option
running ends up diverting dev resources away towards tracking down
and fixing problems with a parallel system that will be going away.
This reverts commit b4b745b720.
This was causing a problem in 01_025_A.anim.blend from the Spring
production files, where selecting one of Autumn's bones would
result in character jumping back to the origin.
Note the relationship we need is from the geometry/object to the curve data,
not the curve object.
Related to T55167, though when copy-on-write is enabled, we still get a crash.
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/
This relations is only to force geometry evaluation to happen
after scene's CoW is done. it was never meant to update geometry
when scene is being tagged.
