For example, the `Bake` node generally does not propagate any anonymous
attributes. That's true regardless of whether it is baked or not. However, if it
is muted, the attributes should be propagated.
Pull Request: https://projects.blender.org/blender/blender/pulls/120887
Along with the 4.1 libraries upgrade, we are bumping the clang-format
version from 8-12 to 17. This affects quite a few files.
If not already the case, you may consider pointing your IDE to the
clang-format binary bundled with the Blender precompiled libraries.
This adds a new `Bake` node which allows saving and loading intermediate geometries.
Typical use cases we want address with this currently are:
* Bake some data for use with a render engine.
* Bake parts of the node tree explicitly for better performance.
For now, the format that is written to disk is not considered to be an import/export format.
It's not guaranteed that data written with one Blender version can be read by another
Blender version. For that it's better to use proper interchange formats. Better support for
those will be added eventually as well. We also plan an `Import Bake` node that allows
reading the blender-specific baked data independent of the Bake node and at different frames.
The baking works very similar to the baking in the simulation zone (UI and implementation
wise). Major differences are:
* The Bake node has a `Bake Still` and `Bake Animation` mode.
* The Bake node doesn't do automatic caching.
Implementation details:
* Refactored how we create the Python operators for moving socket items so that it also
makes sense for non-zones.
* The `ModifierCache` stores an independent map of `SimulationNodeCache` and
`BakeNodeCache`, but both share a common data structure for the actually baked data.
* For baking, the `Bake` node is added as a side-effect-node in the modifier. This will make
sure that the node is baked even if it's currently not connected to the output.
* Had to add a new `DEG_id_tag_update_for_side_effect_request` function that is used
during baking. It's necessary because I want to evaluate the object again even though none
of its inputs changed. The reevaluation is necessary to create the baked data. Using
`DEG_id_tag_update` technically works as well, but has the problem that it also uses the
`DEG_UPDATE_SOURCE_USER_EDIT` flag which (rightly) invalidates simulation caches
which shouldn't happen here.
* Slightly refactored the timeline drawing so that it can also show the baked ranges of
Bake nodes. It does not show anything for baked nodes with a in Still mode though.
* The bake operator is refactored to bake a list of `NodeBakeRequest` which makes the
code easier to follow compared to the previous nested
`ObjectBakeData > ModifierBakeData > NodeBakeData` data structure.
* The bake operators are disabled when the .blend file is not yet saved. This is technically
only necessary when the bake path depends on the .blend file path but seems ok to force
the user anyway (otherwise the bake path may be lost as well if it's set explicitly).
* The same operators are used to bake and delete single bakes in `Bake` nodes and
`Simulation Zones`. On top of that, there are separate operators of baking and deleting all
simulation bakes (those ignore bake nodes).
* The `Bake` node remembers which inputs have been fields and thus may be baked as attributes.
For that it uses an `Is Attribute` flag on the socket item. This is needed because the baked data
may still contain attribute data, even if the inputs to the bake node are disconnected.
* Similar to simulation zones, the behavior of `Bake` nodes is passed into the geometry nodes
evaluation from the outside (from the modifier only currently). This is done by providing the
new `GeoNodesBakeParams` in `GeoNodesCallData` when executing geometry nodes.
Next Steps (mostly because they also involve simulations):
* Visualize nodes that have not been evaluated in the last evaluation.
* Fix issue with seemingly loosing baked data after undo.
* Improve error handling when baked data is not found.
* Show bake node in link drag search.
* Higher level tools for managing bakes.
Pull Request: https://projects.blender.org/blender/blender/pulls/115466
The issue was that a node was supposed to propagate an anonymous
attribute that is only created further to the right in the tree. This does not
during inferencing, where uses of fields can only come to the right of its
creation. Note, all fields coming out of the repeat input/output node are
new field sources during inferencing.
Now, only field sources that are passed from the outside into the repeat zone
can be propagated from the repeat output to the repeat input node.
Solving this also showed another issue where anonymous attributes are
not properly propagated through a repeat zone where there is no link between
the repeat input and output node. In such cases, data is still propagated between
those two nodes when the number of iterations is zero.
The repeat zone needs some special treatment during anonymous attribute
inferencing, because it propagates those attributes directly from the repeat
input to the repeat output node and vice versa.
Now the algorithm uses multiple passes if necessary to reach a stable
inferencing result.
Pull Request: https://projects.blender.org/blender/blender/pulls/113970
Calling an API function after the node panels patch does not internally
tag the node tree with `NTREE_CHANGED_INTERFACE` any more, because the
node tree is not directly accessible from `bNodeTreeInterface`. Before
node panels the API functions for interfaces could tag the tree directly
for later update consideration, which now requires explicit tagging
calls.
The fix is to add a flag and mutex directly to `bNodeTreeInterface`, so
API methods can tag after updates. This mostly copies runtime data
concepts from `bNodeTree`. The `ensure_interface_cache` method is
equivalent to `ensure_topology_cache` and should be called before
accessing `interface_inputs` and similar cache data.
Pull Request: https://projects.blender.org/blender/blender/pulls/111741
Part 3/3 of #109135, #110272
Switch to new node group interfaces and deprecate old DNA and API.
This completes support for panels in node drawing and in node group
interface declarations in particular.
The new node group interface DNA and RNA code has been added in parts
1 and 2 (#110885, #110952) but has not be enabled yet. This commit
completes the integration by
* enabling the new RNA API
* using the new API in UI
* read/write new interfaces from blend files
* add versioning for backward compatibility
* add forward-compatible writing code to reconstruct old interfaces
All places accessing node group interface declarations should now be
using the new API. A runtime cache has been added that allows simple
linear access to socket inputs and outputs even when a panel hierarchy
is used.
Old DNA has been deprecated and should only be accessed for versioning
(inputs/outputs renamed to inputs_legacy/outputs_legacy to catch
errors). Versioning code ensures both backward and forward
compatibility of existing files.
The API for old interfaces is removed. The new API is very similar but
is defined on the `ntree.interface` instead of the `ntree` directly.
Breaking change notifications and detailed instructions for migrating
will be added.
A python test has been added for the node group API functions. This
includes new functionality such as creating panels and moving items
between different levels.
This patch does not yet contain panel representations in the modifier
UI. This has been tested in a separate branch and will be added with a
later PR (#108565).
Pull Request: https://projects.blender.org/blender/blender/pulls/111348
Including <iostream> or similar headers is quite expensive, since it
also pulls in things like <locale> and so on. In many BLI headers,
iostreams are only used to implement some sort of "debug print",
or an operator<< for ostream.
Change some of the commonly used places to instead include <iosfwd>,
which is the standard way of forward-declaring iostreams related
classes, and move the actual debug-print / operator<< implementations
into .cc files.
This is not done for templated classes though (it would be possible
to provide explicit operator<< instantiations somewhere in the
source file, but that would lead to hard-to-figure-out linker error
whenever someone would add a different template type). There, where
possible, I changed from full <iostream> include to only the needed
<ostream> part.
For Span<T>, I just removed print_as_lines since it's not used by
anything. It could be moved into a .cc file using a similar approach
as above if needed.
Doing full blender build changes include counts this way:
- <iostream> 1986 -> 978
- <sstream> 2880 -> 925
It does not affect the total build time much though, mostly because
towards the end of it there's just several CPU cores finishing
compiling OpenVDB related source files.
Pull Request: https://projects.blender.org/blender/blender/pulls/111046
Listing the "Blender Foundation" as copyright holder implied the Blender
Foundation holds copyright to files which may include work from many
developers.
While keeping copyright on headers makes sense for isolated libraries,
Blender's own code may be refactored or moved between files in a way
that makes the per file copyright holders less meaningful.
Copyright references to the "Blender Foundation" have been replaced with
"Blender Authors", with the exception of `./extern/` since these this
contains libraries which are more isolated, any changed to license
headers there can be handled on a case-by-case basis.
Some directories in `./intern/` have also been excluded:
- `./intern/cycles/` it's own `AUTHORS` file is planned.
- `./intern/opensubdiv/`.
An "AUTHORS" file has been added, using the chromium projects authors
file as a template.
Design task: #110784
Ref !110783.
This adds support for running a set of nodes repeatedly. The number
of iterations can be controlled dynamically as an input of the repeat
zone. The repeat zone can be added in via the search or from the
Add > Utilities menu.
The main use case is to replace long repetitive node chains with a more
flexible alternative. Technically, repeat zones can also be used for
many other use cases. However, due to their serial nature, performance
is very sub-optimal when they are used to solve problems that could
be processed in parallel. Better solutions for such use cases will
be worked on separately.
Repeat zones are similar to simulation zones. The major difference is
that they have no concept of time and are always evaluated entirely in
the current frame, while in simulations only a single iteration is
evaluated per frame.
Stopping the repetition early using a dynamic condition is not yet
supported. "Break" functionality can be implemented manually using
Switch nodes in the loop for now. It's likely that this functionality
will be built into the repeat zone in the future.
For now, things are kept more simple.
Remaining Todos after this first version:
* Improve socket inspection and viewer node support. Currently, only
the first iteration is taken into account for socket inspection
and the viewer.
* Make loop evaluation more lazy. Currently, the evaluation is eager,
meaning that it evaluates some nodes even though their output may not
be required.
Pull Request: https://projects.blender.org/blender/blender/pulls/109164
Previously, there were two independent algorithms for analysing how anonymous
attributes are used in a node tree: One that just computed the `aal::RelationsInNode`
for an entire node tree and one that performed a more in depth analysis to
determine how far anonymous attributes should be propagated.
As it turns out, both operations can also be done at the same time and the result
can be cached on the node tree. This reduces the amount of code and allows for
better code reuse.
This simplification is likely only an intermediate step as things will probably have
to be refactored further to support e.g. serial loops (#108896).
A lot of files were missing copyright field in the header and
the Blender Foundation contributed to them in a sense of bug
fixing and general maintenance.
This change makes it explicit that those files are at least
partially copyrighted by the Blender Foundation.
Note that this does not make it so the Blender Foundation is
the only holder of the copyright in those files, and developers
who do not have a signed contract with the foundation still
hold the copyright as well.
Another aspect of this change is using SPDX format for the
header. We already used it for the license specification,
and now we state it for the copyright as well, following the
FAQ:
https://reuse.software/faq/
This adds support for building simulations with geometry nodes. A new
`Simulation Input` and `Simulation Output` node allow maintaining a
simulation state across multiple frames. Together these two nodes form
a `simulation zone` which contains all the nodes that update the simulation
state from one frame to the next.
A new simulation zone can be added via the menu
(`Simulation > Simulation Zone`) or with the node add search.
The simulation state contains a geometry by default. However, it is possible
to add multiple geometry sockets as well as other socket types. Currently,
field inputs are evaluated and stored for the preceding geometry socket in
the order that the sockets are shown. Simulation state items can be added
by linking one of the empty sockets to something else. In the sidebar, there
is a new panel that allows adding, removing and reordering these sockets.
The simulation nodes behave as follows:
* On the first frame, the inputs of the `Simulation Input` node are evaluated
to initialize the simulation state. In later frames these sockets are not
evaluated anymore. The `Delta Time` at the first frame is zero, but the
simulation zone is still evaluated.
* On every next frame, the `Simulation Input` node outputs the simulation
state of the previous frame. Nodes in the simulation zone can edit that
data in arbitrary ways, also taking into account the `Delta Time`. The new
simulation state has to be passed to the `Simulation Output` node where it
is cached and forwarded.
* On a frame that is already cached or baked, the nodes in the simulation
zone are not evaluated, because the `Simulation Output` node can return
the previously cached data directly.
It is not allowed to connect sockets from inside the simulation zone to the
outside without going through the `Simulation Output` node. This is a necessary
restriction to make caching and sub-frame interpolation work. Links can go into
the simulation zone without problems though.
Anonymous attributes are not propagated by the simulation nodes unless they
are explicitly stored in the simulation state. This is unfortunate, but
currently there is no practical and reliable alternative. The core problem
is detecting which anonymous attributes will be required for the simulation
and afterwards. While we can detect this for the current evaluation, we can't
look into the future in time to see what data will be necessary. We intend to
make it easier to explicitly pass data through a simulation in the future,
even if the simulation is in a nested node group.
There is a new `Simulation Nodes` panel in the physics tab in the properties
editor. It allows baking all simulation zones on the selected objects. The
baking options are intentially kept at a minimum for this MVP. More features
for simulation baking as well as baking in general can be expected to be added
separately.
All baked data is stored on disk in a folder next to the .blend file. #106937
describes how baking is implemented in more detail. Volumes can not be baked
yet and materials are lost during baking for now. Packing the baked data into
the .blend file is not yet supported.
The timeline indicates which frames are currently cached, baked or cached but
invalidated by user-changes.
Simulation input and output nodes are internally linked together by their
`bNode.identifier` which stays the same even if the node name changes. They
are generally added and removed together. However, there are still cases where
"dangling" simulation nodes can be created currently. Those generally don't
cause harm, but would be nice to avoid this in more cases in the future.
Co-authored-by: Hans Goudey <h.goudey@me.com>
Co-authored-by: Lukas Tönne <lukas@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/104924
Node tree updates can crash if the tree contains a node group that points at an "undefined" tree type.
This can happen if the tree is linked from a library and the path is lost,
or if a custom (python) tree is used and the script is not run.
The fix is to check if the node group type is valid ("registered") and return an empty list otherwise.
Pull Request: https://projects.blender.org/blender/blender/pulls/105564
Previously, the lifetimes of anonymous attributes were determined by
reference counts which were non-deterministic when multiple threads
are used. Now the lifetimes of anonymous attributes are handled
more explicitly and deterministically. This is a prerequisite for any kind
of caching, because caching the output of nodes that do things
non-deterministically and have "invisible inputs" (reference counts)
doesn't really work.
For more details for how deterministic lifetimes are achieved, see D16858.
No functional changes are expected. Small performance changes are expected
as well (within few percent, anything larger regressions should be reported as
bugs).
Differential Revision: https://developer.blender.org/D16858