Previously, internal links used the same heuristics as most other nodes. However,
this is more problematic here, because I intend to use the same internal links
for the case when no closure is connected. The behavior in this case should not
change in the future if we decide to change the heuristic for internal links for
muted nodes.
This implements bundles and closures which are described in more detail in this
blog post: https://code.blender.org/2024/11/geometry-nodes-workshop-october-2024/
tl;dr:
* Bundles are containers that allow storing multiple socket values in a single
value. Each value in the bundle is identified by a name. Bundles can be
nested.
* Closures are functions that are created with the Closure Zone and can be
evaluated with the Evaluate Closure node.
To use the patch, the `Bundle and Closure Nodes` experimental feature has to be
enabled. This is necessary, because these features are not fully done yet and
still need iterations to improve the workflow before they can be officially
released. These iterations are easier to do in `main` than in a separate branch
though. That's because this patch is quite large and somewhat prone to merge
conflicts. Also other work we want to do, depends on this.
This adds the following new nodes:
* Combine Bundle: can pack multiple values into one.
* Separate Bundle: extracts values from a bundle.
* Closure Zone: outputs a closure zone for use in the `Evaluate Closure` node.
* Evaluate Closure: evaluates the passed in closure.
Things that will be added soon after this lands:
* Fields in bundles and closures. The way this is done changes with #134811, so
I rather implement this once both are in `main`.
* UI features for keeping sockets in sync (right now there are warnings only).
One bigger issue is the limited support for lazyness. For example, all inputs of
a Combine Bundle node will be evaluated, even if they are not all needed. The
same is true for all captured values of a closure. This is a deeper limitation
that needs to be resolved at some point. This will likely be done after an
initial version of this patch is done.
Pull Request: https://projects.blender.org/blender/blender/pulls/128340
Adds support for the "Menu" socket type in for-each-element zones. This
only includes field inputs and their matching per-element values, but
not outputting attributes of type Menu (Menu attributes are not
generally supported at this point).
A dedicated enum propagation function is added for the zone input node.
This isn't technically necessary: the first 2 inputs and outputs should
be ignored but are not menus anyway. However, this is clearer and
provides a place for future changes.
Pull Request: https://projects.blender.org/blender/blender/pulls/128106
This adds a new type of zone to Geometry Nodes that allows executing some nodes
for each element in a geometry.
## Features
* The `Selection` input allows iterating over a subset of elements on the set
domain.
* Fields passed into the input node are available as single values inside of the
zone.
* The input geometry can be split up into separate (completely independent)
geometries for each element (on all domains except face corner).
* New attributes can be created on the input geometry by outputting a single
value from each iteration.
* New geometries can be generated in each iteration.
* All of these geometries are joined to form the final output.
* Attributes from the input geometry are propagated to the output
geometries.
## Evaluation
The evaluation strategy is similar to the one used for repeat zones. Namely, it
dynamically builds a `lazy_function::Graph` once it knows how many iterations
are necessary. It contains a separate node for each iteration. The inputs for
each iteration are hardcoded into the graph. The outputs of each iteration a
passed to a separate lazy-function that reduces all the values down to the final
outputs. This final output can have a huge number of inputs and that is not
ideal for multi-threading yet, but that can still be improved in the future.
## Performance
There is a non-neglilible amount of overhead for each iteration. The overhead is
way larger than the per-element overhead when just doing field evaluation.
Therefore, normal field evaluation should be preferred when possible. That can
partially still be optimized if there is only some number crunching going on in
the zone but that optimization is not implemented yet.
However, processing many small geometries (e.g. each hair of a character
separately) will likely **always be slower** than working on fewer larger
geoemtries. The additional flexibility you get by processing each element
separately comes at the cost that Blender can't optimize the operation as well.
For node groups that need to handle lots of geometry elements, we recommend
trying to design the node setup so that iteration over tiny sub-geometries is
not required.
An opposite point is true as well though. It can be faster to process more
medium sized geometries in parallel than fewer very large geometries because of
more multi-threading opportunities. The exact threshold between tiny, medium and
large geometries depends on a lot of factors though.
Overall, this initial version of the new zone does not implement all
optimization opportunities yet, but the points mentioned above will still hold
true later.
Pull Request: https://projects.blender.org/blender/blender/pulls/127331
Previously, it was only possible to bake to disk with geometry nodes. This patch
adds support for storing the baked data directly in the .blend file.
By default, new bakes are stored in the .blend file now. Whether a new bake
should be packed or stored on disk can be configured in two places: in the
properties of the bake node and in the bake panel of the modifier. These
settings don't affect existing bakes, only the next bake.
To unpack or pack an individual bake, there is a new operator button next to the
bake button. The icon and the label below indicate where the bake is currently
stored. The label now also contains the size of the bake.
To unpack or pack all bakes, the `File > External Data > Pack Resources / Unpack
Resources` operators can be used. The unpack operator also has a new title that
mentions the number if individual files separate from the number of bakes. This
works better than just listing a number of files because a bake can consist of
many files.
Pull Request: https://projects.blender.org/blender/blender/pulls/124230
By capturing multiple attributes with one node, the user can make sure that those
are evaluated together in the same context. This can be quite a bit more efficient
compared to capturing multiple fields separately (also because we don't optimize
grouping multiple capture nodes together yet).
The change is fully backward compatible. Forward compatibility has been added
for some cases. Especially, files created in older versions that are saved with this
newer version will still work in the older version.
Co-authored-by: Hans Goudey <hans@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/121665
This adds the same overlay that already exists for the bake node to the simulation output node.
Without this, it's quite hard to see if the simulation zone is baked or not currently.
Pull Request: https://projects.blender.org/blender/blender/pulls/121497
This changes the menu switch socket to use the socket-items system
(`NOD_socket_items.hh`) that is already used by the simulation zone, repeat
zone, bake node and index switch node. By using this system, the per-node
boilerplate can be removed significantly. This is especially important as we
plan to have dynamic socket amounts in more nodes in the future.
There are some user visible changes which make the node more consistent with
others:
* Move the menu items list into the properties panel as in 0c585a1b8a.
* Add an extend socket.
* Duplicating a menu item keeps the name of the old one.
There is also a (backward compatible) change in the Python API: It's now
possible to directly access `node.enum_items` and `node.active_index` instead of
having to use `node.enum_definition.enum_items`. This is consistent with the
other nodes. For backward compatibility, `node.enum_definition` still exists,
but simply returns the node itself.
Many API functions from `NodeEnumDefinition` like
`NodeEnumDefinition::remove_item` have been removed. Those are not used anymore
and are unnecessary boilerplate. If ever necessary, they can be implemented back
in terms of the socket-items system.
The socket-items system had to be extended a little bit to support the case for
the menu switch node where each socket item has a name but no type. Previously,
there was the case without name and type in the index switch node, and the case
with both in the bake node and zones. The system was trivial to extend to this
case.
Pull Request: https://projects.blender.org/blender/blender/pulls/121234
`NOD_zone_socket_items.hh` contained code for different nodes. It's better to
split this into headers per node, because that scales better. Also it helps to
keep the code for each individual node more closely together.
Pull Request: https://projects.blender.org/blender/blender/pulls/120945
