The general idea of this change is to have a runtime data pointer
in the ModifierData, so it can be preserved through copy-on-write
updates by the dependency graph.
This is where subdivision surface modifier can store its topology
cache, so it is not getting trashed on every copy-on-write which
is happening when moving a vertex.
Similar mechanism should be used by multiresolution, dynamic paint
and some other modifiers which cache evaluated data.
This fixes T61746.
Thing to keep in mind, that there are more reports about slow
subdivision surface in the tracker, but that boils down to the
fact that those have a lot of extraordinary vertices, and hence
a lot slower to evaluated topology.
Other thing is, this speeds up oeprations which doesn't change
topology (i.e. moving vertices).
Reviewers: brecht
Reviewed By: brecht
Maniphest Tasks: T61746
Differential Revision: https://developer.blender.org/D4541
We already have different storages for cddata of verts, edges etc.,
'simply' do the same for the mask flags we use all around Blender code
to request some data, or limit some operation to some layers, etc.
Reason we need this is that some cddata types (like Normals) are
actually shared between verts/polys/loops, and we don’t want to generate
clnors everytime we request vnors!
As a side note, this also does final fix to T59338, which was the
trigger for this patch (need to request computed loop normals for
another mesh than evaluated one).
Reviewers: brecht, campbellbarton, sergey
Differential Revision: https://developer.blender.org/D4407
This is what modifiers are to use to indicate that they depend
on a transformation of the object itself.
Currently should be no functional changes, but in the future
this will allow to easily change transform operation depending
on whether there is a simulation associated with the object.
Turns out most of our 'local working copy' cases can use same set of
flags.
Note that this commit adds LIB_ID_COPY_CACHES to all our local meshes
copying, however this is no-op since that flag is unused during mesh
copying... We may want to add another set of flags without that one at
some point, but for now it would not be useful imho.
BF-admins agree to remove header information that isn't useful,
to reduce noise.
- BEGIN/END license blocks
Developers should add non license comments as separate comment blocks.
No need for separator text.
- Contributors
This is often invalid, outdated or misleading
especially when splitting files.
It's more useful to git-blame to find out who has developed the code.
See P901 for script to perform these edits.
Was happening due to missing relation from geometry to
transform component. Did not happen in old dependency
graph because that one could never evaluate geometry
prior to transform.
There was no documentation at all, some very bad practices (like using
G.debug_value > 0 as some sort of global debug print switch), and even
an overlapping use of '1' value...
Also, python setter did not check for valid range (since this is a
short, not an int).
The modifier is still quite slow; this could be due to caches being written
to a CoW datablock instead of the original one. More investigation is
needed.
The contents of the ModifierEvalContext struct are constant while iterating
over the modifier stack. The struct thus should be only created once, outside
any loop over the modifiers.
Makes the follow changes:
- Add new `deform*` and `apply*` function pointers to `ModifierTypeInfo` that take `Mesh`, and rename the old functions to indicate that they take `DerivedMesh`. These new functions are currently set to `NULL` for all modifiers.
- Add wrapper `modifier_deform*` and `modifier_apply*` functions in two variants: one that works with `Mesh` and the other which works with `DerivedMesh` that is named with `*_DM_depercated`. These functions check which type of data the modifier supports and converts if necessary
- Update the rest of Blender to be aware and make use of these new functions
The goal of these changes is to make it possible to port to using `Mesh` incrementally without ever needing to enter into a state where modifiers don't work. After everything has been ported over the old functions and wrappers could be removed.
Reviewers: campbellbarton, sergey, mont29
Subscribers: sybren
Tags: #bf_blender_2.8
Differential Revision: https://developer.blender.org/D3155
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
2.8x branch added bContext arg in many places,
pass eval-context instead since its not simple to reason about what
what nested functions do when they can access and change almost anything.
Also use const to prevent unexpected modifications.
This fixes crash loading files with shadows,
since off-screen buffers use a NULL context for rendering.
Note that some little parts of code have been dissabled because eval_ctx
was not available there. This should be resolved once DerivedMesh is
replaced.
These bits became obsolete with the new layer system, so we can
simplify some code around them or avoid existing workarounds which
were trying to keep things working for them.
There are still work needed to be done for on_visible_change to
avoid unnecessary updates, but that can also happen later.
Better to have clear way to tell whether flag is parameter for
BKE_library_foreach_ID_link(), parameter for its callback function, or
return value from this callback function.
Current implementation more or less indiscriminately links physics
objects to colliders and forces, ignoring precise details of layer
checks and collider groups. The new depsgraph seemed to lack some
such links at all. The relevant code in modifiers suffers from a
lot of duplication.
Different physics simulations use independent implementations of
collision and similar things, which results in a lot of variance:
* Cloth collides with objects on same or visible layer with dupli.
* Softbody collides with objects on same layer without dupli.
* Non-hair particles collide on same layer with dupli.
* Smoke uses same code as cloth, but needs different modifier.
* Dynamic paint "collides" with brushes on any layer without dupli.
Force fields with absorption also imply dependency on colliders:
* For most systems, colliders are selected from same layer as field.
* For non-hair particles, it uses the same exact set as the particles.
As a special quirk, smoke ignores smoke flow force fields; on the other
hand dependency on such field implies dependency on the smoke domain.
This introduces two utility functions each for old and new depsgraph
that are flexible enough to handle all these variations, and uses them
to handle particles, cloth, smoke, softbody and dynpaint.
One thing to watch out for is that depsgraph code shouldn't rely on
any properties that don't cause a graph rebuild when changed. This
was violated in the original code that was building force field links,
while taking zero field weights into account.
This change may cause new dependency cycles in cases where necessary
dependencies were missing, but may also remove cycles in situations
where unnecessary links were previously created. It's also now possible
to solve some cycles by switching to explicit groups, since they are
now properly taken into account for dependencies.
Differential Revision: https://developer.blender.org/D2141
This commit integrates the work done so far on the new dependency graph system,
where goal was to replace legacy depsgraph with the new one, supporting loads of
neat features like:
- More granular dependency relation nature, which solves issues with fake cycles
in the dependencies.
- Move towards all-animatable, by better integration of drivers into the system.
- Lay down some basis for upcoming copy-on-write, overrides and so on.
The new system is living side-by-side with the previous one and disabled by
default, so nothing will become suddenly broken. The way to enable new depsgraph
is to pass `--new-depsgraph` command line argument.
It's a bit early to consider the system production-ready, there are some TODOs
and issues were discovered during the merge period, they'll be addressed ASAP.
But it's important to merge, because it's the only way to attract artists to
really start testing this system.
There are number of assorted documents related on the design of the new system:
* http://wiki.blender.org/index.php/User:Aligorith/GSoC2013_Depsgraph#Design_Documents
* http://wiki.blender.org/index.php/User:Nazg-gul/DependencyGraph
There are also some user-related information online:
* http://code.blender.org/2015/02/blender-dependency-graph-branch-for-users/
* http://code.blender.org/2015/03/more-dependency-graph-tricks/
Kudos to everyone who was involved into the project:
- Joshua "Aligorith" Leung -- design specification, initial code
- Lukas "lukas_t" Toenne -- integrating code into blender, with further fixes
- Sergey "Sergey" "Sharybin" -- some mocking around, trying to wrap up the
project and so
- Bassam "slikdigit" Kurdali -- stressing the new system, reporting all the
issues and recording/writing documentation.
- Everyone else who i forgot to mention here :)
This way it doesn't have to be stored as DNA runtime pointers or passed
down as a function argument. Currently there is now no property or
button to enable debugging, this will be added again later.
