When active dependency graph is evaluated, it will apply animation,
drivers and scalar evaluation data (such as object matrix) to an
original datablock. This way operators and tools can easily read
data from original datablock.
This will simplify porting them to copy-on-write, and solve issues
when some operator will allocate new datablock based on original one,
and will want to read data from it.
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 introduces a new depsgraph API for getting updated datablocks,
rather than getting it from bpy.data.
* depsgraph.ids_updated gives a list of all datablocks in the depsgraph
which have been updated.
* depsgraph.id_type_updated('TYPE') is true if any datablock of the given
type has been added, removed or modified.
More API updates are coming to properly handle multiple depsgraphs and
finer update granularity, but this should make Cycles work again.
As was decided at today's dev kickoff, we're now moving to having
Copy-on-Write enabled by default, as 2.8 is barely functional with
it off.
To run Blender *without* COW (e.g. for testing), use:
--disable-copy-on-write
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/
The depsgraph was always created within a fixed evaluation context. Passing
both risks the depsgraph and evaluation context not matching, and it
complicates the Python API where we'd have to expose both which is not so
easy to understand.
This also removes the global evaluation context in main, which assumed there
to be a single active scene and view layer.
Differential Revision: https://developer.blender.org/D3152
This was only used for viewport rendering, where we can just pass the engine
type directly. There is no technical reason why we can't draw the same depsgrpah
with different render engines.
It also led to some weird things like requiring a render engine for snapping
and raycast API functions.
Differential Revision: https://developer.blender.org/D3145
Scene, view layer and mode are now set in the constructor and never changed.
Time is updated on frame changes to indicate which frame is being or has been
evaluated last.
This is a step towards making EvaluationContext obsolete.
Differential Revision: https://developer.blender.org/D3144
Now the only missing bit seems to be in Cycles to pass depsgraph to
builtin_image_float_pixels().
Ideally we could get evaluation context instead of using depsgraph + settings.
But for the other rna EvaluationContext functions this is how we are doing.
Reviewers: sergey, brecht
Differential Revision: https://developer.blender.org/D3087
User notes
----------
Compositing, rendering of multi-layers in Eevee should be fully working now.
Development notes
-----------------
Up until now we were still using the same depsgraph for rendering and viewport
evaluation. And we had to go out of our ways to be sure the depsgraphs were
updated.
Now we iterate over the (to be rendered) view layers and create a depsgraph to
each one, fully evaluated and call the render engines (Cycles, Eevee, ...) with
this viewlayer/depsgraph/evaluation context.
At this time we are not handling data persistency, Depsgraph is created from
scratch prior to rendering each frame. So I got rid of most of the partial
update calls we had during the render pipeline.
Cycles: Brecht Van Lommel did a patch to tackle some of the required Cycles
changes but this commit mark these changes as TODOs. Basically Cycles needs to
render one layer at a time.
Reviewers: sergey, brecht
Differential Revision: https://developer.blender.org/D3073
Those are unused, and not clear whether we will ever support this.
Seems to be better having more like "component" tags, would be less magic
involved to guess what exactly is to be tagged.
This commit effectively reverts fix T45702 done in 067fe2719a.
Reasoning:
- Blender Internal is being replaced with Eevee, and will be removed entirely
rather soon.
- All render engines are planned to have own depsgraph, so such threading
conflicts should no longer be an issue.
- We don't want to spend time on porting workarounds for EOL things to a new
design. Less code -- faster the work :)
- If such notifications will end up needed for some other cases, we would
need to re-implement this a more proper depsgraph tagging/flushing and make
it to work with all copy-on-write datablocks and everything.
There might be much more logic involved there, also we might not know proper
evaluated CoW pointer there yet. So we leave this to dependency graph to
decide what exactly to do here.
This is crucial bit since batch cache is stored in the evaluated object,
meaning we can't tag it's hatch cache dirty from the notifier system.
Not easily at least. Better to leave this job to depsgraph, it knows
all the copies of data.
The RenderResult struct still has a listbase of RenderLayer, but that's ok
since this is strictly for rendering.
* Subversion bump (to 2.80.2)
* DNA low level doversion (renames) - only for .blend created since 2.80 started
Note: We can't use DNA_struct_elem_find or get file version in init_structDNA,
so we are manually iterating over the array of the SDNA elements instead.
Note 2: This doversion change with renames can be reverted in a few months. But
so far it's required for 2.8 files created between October 2016 and now.
Reviewers: campbellbarton, sergey
Differential Revision: https://developer.blender.org/D2927
This is a first step towards an updated API where we pass explicit graph rather
than a scene. This is because we can no longer deduct which graph to use since
it will depend on a context.
Will happen in several steps, so bisecting will not be such a pain.
This way evaluation routines will know which exact depsgraph evaluation
is happening for.
Mainly needed to get evaluation flags associated with ID nodes.
Before it was a compile time option which was not very easy to use or test. Now
the project is getting more mature, so very soon we will be able to call for a
public tests of limited features.
The copy-on-write (which includes animation, modifiers) is enabled using
--enable-copy-on-write command line argument.
Engine is not stored in WorkSpaces. That defines the "context" engine, which
is used for the entire UI.
The engine used for the poll of nodes (add node menu, new nodes when "Use Nodes")
is obtained from context.
Introduce a ViewRender struct for viewport settings that are defined for
workspaces and scene. This struct will be populated with the hand-picked
settings that can be defined per workspace as per the 2.8 design.
* use_scene_settings
* properties editor: workshop + organize context path
Use Scene Settings
==================
For viewport drawing, Workspaces have an option to use the Scene render
settings (F12) instead of the viewport settings.
This way users can quickly preview the final render settings, engine and
View Layer. This will affect all the editors in that workspace, and it will be
clearly indicated in the top-bar.
Properties Editor: Add Workspace and organize context path
==========================================================
We now have the properties of:
Scene, Scene > Layer, Scene > World, Workspace
[Scene | Workspace] > Render Layer > Object
[Scene | Workspace] > Render Layer > Object > Data
(...)
Reviewers: Campbell Barton, Julian Eisel
Differential Revision: https://developer.blender.org/D2842
