We can not access ensured-to-be-evaluated dependency graph from the
render API: some of it is running from within evaluation which makes
it possible for engines to access list of evaluated IDs.
Solved by passing dependency graph to viewport functions, similar to
the final render functions.
One of the usecases is to create mesh from an object is a manner similar to
how Apply Modifiers does it, and have it in the bmain so it can be referenced
by other objects.
This usecase is something what went unnoticed in the previous API changes, so
here is a followup.
Summary of changes:
* bpy.meshes.new_from_object() behaves almost the same as before this change.
The difference now is that it now ensures all referenced data-blocks are
original (for example, materials referenced by the mesh).
* object.to_mesh() now creates free-standing Mesh data-block which is outside
of any bmain. The object owns it, which guarantees the memory never leaks.
It is possible to force free memory by calling object.to_mesh_clear().
Reviewers: brecht
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D4875
Main goal here is to make it obvious and predictable about
what is going on.
Summary of changes.
- Access to dependency graph is now only possible to a fully evaluated
graph. This is now done via context.evaluated_depsgraph_get().
The call will ensure both relations and datablocks are updated.
This way we don't allow access to some known bad state of the graph,
and also making explicit that getting update dependency graph is not
cheap.
- Access to evaluated ID is now possible via id.evaluated_get().
It was already possible to get evaluated ID via dependency graph,
but that was a bit confusing why access to original is done via ID
and to evaluated via depsgraph.
If datablock is not covered by dependency graph it will be returned
as-is.
- Similarly, request for original from an ID which is not evaluated
will return ID as-is.
- Removed scene.update().
This is very expensive to update all the view layers.
- Added depsgraph.update().
Now when temporary changes to objects are to be done, this is to
happen on original object and then dependency graph is to be
updated.
- Changed object.to_mesh() to behave the following way:
* When is used for original object modifiers are ignored.
For meshes this acts similar to mesh-copy, not very useful but
allows to keep code paths similar (i.e. for exporter which has
Apply Modifiers option it's only matter choosing between original
and evaluated object, the to_mesh() part can stay the same).
For curves this gives a mesh which is constructed from displist
without taking own modifiers and modifiers of bevel/taper objects
into account.
For metaballs this gives empty mesh.
Polygonization of metaball is not possible from a single object.
* When is used for evaluated object modifiers are always applied.
In fact, no evaluation is happening, the mesh is either copied
as-is, or constructed from current state of curve cache.
Arguments to apply modifiers and calculate original coordinates (ORCO,
aka undeformed coordinates) are removed. The ORCO is to be calculated
as part of dependency graph evaluation.
File used to regression-test (a packed Python script into .blend):
{F7033464}
Patch to make addons tests to pass:
{F7033466}
NOTE: I've included changes to FBX exporter, and those are addressing
report T63689.
NOTE: All the enabled-by-default addons are to be ported still, but
first want to have agreement on this part of changes.
NOTE: Also need to work on documentation for Python API, but, again,
better be done after having agreement on this work.
Reviewers: brecht, campbellbarton, mont29
Differential Revision: https://developer.blender.org/D4834
In 2.7x UV sculpt was a kind of sub-mode
(a toggle with it's own key-map & drawing code).
Move this to an operator that uses the tool-system,
this simplifies internal logic, especially brush selection
which now matches sculpt and other paint modes.
- Remove toggle used to enable uv sculpt.
- Expose the brush, which was already used but there was no way to
select different brushes.
- Make UV sculpt use paint paint tool slots
(using brushes how all other paint mode currently do).
- Move UV Sculpt keymap to the tools keymap.
- Remove Q to toggle UV sculpt mode,
S/P/G keys to switch tools.
In a separate step, all new functions should be added.
However, the best way to do this, is not clear yet.
A list of functions, that have to be added is available
in D4280.
Differential Revision: https://developer.blender.org/D4280
As exposed in T62406, we can have some rare cases of crashes due to
memory re-allocation happening outside of expected scenarii.
Ideally this should be re-designed, but at least keep track of those
known exceptions to general rules...
* Added a TL;DR first paragraph summarizing that one shall not keep any
reference to Blender data when modifying its container.
* Added some info about fact that adding items to some data containers
(like Collection) can also invalidate existing items (due to array
re-allocation).
* Added a Do/Don't example which shows a crash after adding some items
to a collection.
Related to T61297.
There is a new `bpy.app.timers` api.
For more details, look in the Python API documentation.
Reviewers: campbellbarton
Differential Revision: https://developer.blender.org/D3994
The HTML title did not make it clear that these are docs for the API rather
than a general Blender documentation. Some of the page titles were also too
long and redundant.
I think this example does not belong into the api docs and certainly not in the place where it was until now.
Maybe this can become a template in Blender but personally I don't see much value in it as an "official example" because it is hard to see what is going on exactly.
There are a few other examples that show how to use the GPUOffScreen object now.
- Was setting active state, making it necessary to backup/restore
active object in cases where this isn't needed.
Existing scripts are explicitly setting the active object when needed.
- Use a boolean select arg (toggle selection wasn't used anywhere).
- Add an optional view layer argument since scripts should be able to
operate outside the user context.
RNA's ViewLayer would present 'first level' of layer collection as a
list (collection property), when it is actually now only a single item,
same as the scene's master collection.
Note: did not try to update view_layer python tests, those are already
fully broken for quiet some time I guess (they still assume
view_layer.collections to be mutable e.g.)...
