Commit Graph

107 Commits

Author SHA1 Message Date
Jacques Lucke
dbe2c2707c Geometry Nodes: extract separate geometry code to separate file 2024-02-01 13:33:06 +01:00
Jacques Lucke
fcc17780a8 Geometry Nodes: extract geometry transform functions to separate file 2024-02-01 13:18:39 +01:00
Jacques Lucke
7042db684f Cleanup: move some geometry field inputs to more correct header 2024-02-01 12:43:39 +01:00
Jacques Lucke
70465387cd Cleanup: merge simulation input and output nodes and extract mix geometries function
The simulation input and output node are closely related and also share some code.
That's easier to handle if they are in the same file.

I also extracted out the code to mix geometries.

Pull Request: https://projects.blender.org/blender/blender/pulls/117713
2024-02-01 11:16:29 +01:00
Jacques Lucke
2d2b087fcf Geometry Nodes: support baking data block references
With this patch, materials are kept intact in simulation zones and bake nodes
without any additional user action.

This implements the design proposed in #108410 to support referencing
data-blocks (only materials for now) in the baked data. The task also describes
why this is not a trivial issue. A previous attempt was implemented in #109703
but it didn't work well-enough.

The solution is to have an explicit `name (+ library name) -> data-block`
mapping that is stored in the modifier for each bake node and simulation zone.
The `library name` is necessary for it to be unique within a .blend file. Note
that this refers to the name of the `Library` data-block and not a file path.
The baked data only contains the names of the used data-blocks. When the baked
data is loaded, the correct material data-block is looked up from the mapping.

### Automatic Mapping Generation

The most tricky aspect of this approach is to make it feel mostly automatic.
From the user point-of-view, it should just work. Therefore, we don't want the
user to have to create the mapping manually in the majority of cases. Creating
the mapping automatically is difficult because the data-blocks that should
become part of the mapping are only known during depsgraph evaluation. So we
somehow have to gather the missing data blocks during evaluation and then write
the new mappings back to the original data.

While writing back to original data is something we do in some cases already,
the situation here is different, because we are actually creating new relations
between data-blocks. This also means that we'll have to do user-counting. Since
user counts in data-blocks are *not* atomic, we can't do that from multiple
threads at the same time. Also, under some circumstances, it may be necessary to
trigger depsgraph evaluation again after the write-back because it actually
affects the result.

To solve this, a small new API is added in `DEG_depsgraph_writeback_sync.hh`. It
allows gathering tasks which write back to original data in a synchronous way
which may also require a reevaluation.

### Accessing the Mapping

A new `BakeDataBlockMap` is passed to geometry nodes evaluation by the modifier.
This map allows getting the `ID` pointer that should be used for a specific
data-block name that is stored in baked data. It's also used to gather all the
missing data mappings during evaluation.

### Weak ID References

The baked/cached geometries may have references to other data-blocks (currently
only materials, but in the future also e.g. instanced objects/collections).
However, the pointers of these data-blocks are not stable over time. That is
especially true when storing/loading the data from disk, but also just when
playing back the animation. Therefore, the used data-blocks have to referenced
in a different way at run-time.

This is solved by adding `std::unique_ptr<bake::BakeMaterialsList>` to the
run-time data of various geometry data-blocks. If the data-block is cached over
a longer period of time (such that material pointers can't be used directly), it
stores the material name (+ library name) used by each material slot. When the
geometry is used again, the material pointers are restored using these weak name
references and the `BakeDataBlockMap`.

### Manual Mapping Management

There is a new `Data-Blocks` panel in the bake settings in the node editor
sidebar that allows inspecting and modifying the data-blocks that are used when
baking. The user can change what data-block a specific name is mapped to.

Pull Request: https://projects.blender.org/blender/blender/pulls/117043
2024-02-01 09:21:55 +01:00
Lukas Tönne
e470edf3e1 Geometry Nodes: initial Volume Grid socket support
This is the initial implementation for the volume grid sockets that has been
discussed during the November 2023 geometry nodes workshop.

It adds initial support for passing volume grids around in sockets. Furthermore,
it adds two new nodes. Both are initially hidden under the "New Volume Nodes"
experimental option until we have a few mode nodes.
* **Get Named Grid**: Gets or extracts a volume grid from a volume geometry
  based on the grid's name.
* **Store Named Grid**: Puts a volume grid back into a volume with a name.

`SocketValueVariant` is extended to support grids besides single values and fields.

Next steps:
* Implement grid socket shape and inferencing (currently, they just look like
  single values).
* Add implicit conversions between grid types.
* Implement nodes that operate on the grids (#116021).
* Improved spreadsheet and viewer support.

Links:
* https://devtalk.blender.org/t/volumes-in-geometry-nodes-proposal/31917
* https://devtalk.blender.org/t/2023-11-06-geometry-nodes-workshop-notes/32007#volumes-3

Co-authored-by: Jacques Lucke <jacques@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/115270
2023-12-20 22:33:17 +01:00
Hans Goudey
19001c9e6c Cleanup: Move attribute domain enum to C++ header, use enum class
Each value is now out of the global namespace, so they can be shorter
and easier to read. Most of this commit just adds the necessary casting
and namespace specification. `enum class` can be forward declared since
it has a specified size. We will make use of that in the next commit.
2023-12-20 13:25:28 -05:00
Jacques Lucke
70a53a815e Cleanup: avoid openvdb include in general in common header 2023-12-20 15:59:44 +01:00
Jacques Lucke
59c84ee95b Cleanup: extract function to show missing openvdb error message 2023-12-20 15:58:56 +01:00
Hans Goudey
5de57e7001 Refactor: Move evaluate on domain field input to be reusable
This is used in #116066 to find the curve selection on the point
domain without having a user-visible difference in behavior.
2023-12-18 10:06:38 -05:00
Hans Goudey
6a1009c9f8 Cleanup: Remove const for Span and by-value types in headers 2023-12-13 09:39:03 -05:00
Jacques Lucke
b7a476ef03 Geometry Nodes: make function for mixing baked data more reusable
The bake node will need this as well (#115466).
2023-12-01 17:13:31 +01:00
Lukas Tönne
c845233d1c Nodes: Move ValueOrField struct into blenkernel
This struct is currently defined in the `functions` module but not actually used there. It's only used by the geometry nodes module, with an indirect dependency from blenkernel via simulation zone baking. This scope is problematic when adding grids as socket data, which should not be part of the functions module.

The `ValueOrField` struct is now moved to blenkernel, so it can be more easily extended to other kinds of data that might be passed around by geometry nodes sockets in future. No functional changes.

Pull Request: https://projects.blender.org/blender/blender/pulls/115087
2023-11-18 13:11:39 +01:00
Iliya Katueshenock
6e2fc77e7f Fix #114993: wrong entry in Split to Instances domain dropdown
Pull Request: https://projects.blender.org/blender/blender/pulls/115005
2023-11-16 18:29:34 +01:00
Hans Goudey
600a133521 Geometry Nodes: Convert four nodes to use rotation socket
Convert the vector socket from four nodes to a rotation socket, adding
versioning to insert the conversion nodes and change the default values
where necessary.
- Distribute Points on Faces
- Instance on Points
- Rotate Instances
- Transform Geometry

Implicit conversions from vectors and floats, and to vectors have been
added, though using rotation sockets directly can be faster, since converting
to and from Euler rotations is slow. Conversion nodes are not inserted
by versioning if the implicit conversions can be used.

This change is not forward compatible with 3.6, and socket values
are lost when opening 4.1 files in 4.0. The correct socket types are
added back in old versions, though newly added conversion nodes
may have to be removed.

Pull Request: https://projects.blender.org/blender/blender/pulls/111482
2023-11-15 18:56:00 +01:00
Iliya Katueshenock
bd6db0acea Cleanup: Nodes: unify data type conversion functions
Pull Request: https://projects.blender.org/blender/blender/pulls/113744
2023-10-16 19:09:07 +02:00
Falk David
3931a54e08 GPv3: Initial Geometry Nodes support
This implements the core changes for this design: https://devtalk.blender.org/t/grease-pencil-integration-into-geometry-nodes/31220

The changes include:
* Add `CustomData` for layer attributes
* Add attribute support for the `GreasePencilComponent` to read/write layer attributes. Also introduces a `Layer` domain.
* Implement a `GreasePencilLayerFieldContext` and make `GeometryFieldContext` work with grease pencil layers.
* Implement `Set Position` node for `Grease Pencil`.

Note: These changes are only accessible/visible with the `Grease Pencil 3.0` experimental flag enabled.
Co-authored-by: Jacques Lucke <jacques@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/112535
2023-10-10 16:49:30 +02:00
Jacques Lucke
0b3daea393 Geometry Nodes: use declaration builder for simulation zone 2023-10-08 14:14:22 +02:00
Jacques Lucke
b6a3ac5a12 Geometry Nodes: use declaration builder for repeat zone 2023-10-08 13:58:22 +02:00
Hans Goudey
7344c7875a Geometry: Move mesh primitives from nodes to geometry module
This makes the code reusable in a few more places,
particularly by tests for a new boolean implementation
also defined in the geometry module.

It also makes the way some primitives are reused among
different nodes a bit clearer.

Pull Request: https://projects.blender.org/blender/blender/pulls/112255
2023-09-11 22:49:41 +02:00
Hans Goudey
974edc5885 Cleanup: Remove unnecessary "add node search"
Now that specific menus can be searched directly (see 7f9d51853c),
there is no need to maintain separate search functionality for adding
nodes. This PR removes the add node search. In a way this brings us
closer to the `NodeItem` situation before, but the setup is more
flexible since the menus are more standard and easier to customize.

In the few ways we customized the node search items before, this gives
us the same results as before. Overall the searching is less flexible,
but I think that is just a tradeoff we have to accept for the simplicity
of searching menus. In the future menus could be made more dynamic,
with each builtin node's menu path stored on the node type, similar to
assets. That might be a nice compromise. In the meantime this code
is just dead weight.

Pull Request: https://projects.blender.org/blender/blender/pulls/112056
2023-09-11 18:36:09 +02:00
Jacques Lucke
7f00cfeab4 Cleanup: move bake items code to separate namespace 2023-09-03 13:37:50 +02:00
Jacques Lucke
da8ad3c2b6 Geometry Nodes: simplify bake state api
This introduces `BakeState` and `BakeStateRef` to replace
the use of `Map<int, BakeItem pointer>` in various places.
2023-09-01 11:25:36 +02:00
Jacques Lucke
e92c59bc9b Geometry Nodes: refactor simulation storage and how simulation nodes access it
Goals of the refactor:
* Internal support for baking individual simulation zones (not exposed in the UI yet).
* More well-defined access to simulation data in geometry nodes. Especially, it
  should be more obvious where data is modified. A similar approach should also
  work for the Bake node.

Previously, there were a bunch of simulation specific properties in `GeoNodesModifierData`
and then the simulation input and output nodes would have to figure out what to do with that
data. Now, there is a new `GeoNodesSimulationParams` which controls the behavior of
simulation zones. Contrary to before, different simulation zones can now be handled
independently, even if that is not really used yet. `GeoNodesSimulationParams` has to be
subclassed by a user of the geometry nodes API. The subclass controls what each simulation
input and output node does. This some of the logic that was part of the node before, into
the modifier.

The way we store simulation data is "transposed". Previously, we stored zone data per
frame, but now we store frame data per zone. This allows different zones to be more
independent. Consequently, the way the simulation cache is accessed changed. I kept
things simpler for now, avoiding many of the methods we had before, and directly
accessing the data more often which is often simple enough. This change also makes
it theoretically possible to store baked data for separate zones independently.
A downside of this is, that existing baked data can't be read anymore. We don't really
have compatibility guarantees for this format yet, so it's ok. Users will have to bake again.
The bake folder for the modifier now contains an extra subfolder for every zone.

Drawing the cached/baked frames in the timeline is less straight forward now. Currently,
it just draws the state of one of the zones, which usually is identical to that of all other
zones. This will change in the future though, and then the timeline drawing also needs
some new UI work.

Pull Request: https://projects.blender.org/blender/blender/pulls/111623
2023-08-31 16:28:03 +02:00
Iliya Katueshenock
cbf8bb9eb9 Nodes: move more rna code to geometry node file
Continuation of 63fd2575e6.
Only geometry nodes with inline enum arrays, shared arrays and filter functions.

Pull Request: https://projects.blender.org/blender/blender/pulls/111329
2023-08-29 12:15:40 +02:00
Aras Pranckevicius
2f060706a4 Cleanup: fewer BLI_color.hh et al includes
Include counts of some headers while making full blender build:
- BLI_color.hh 1771 -> 1718
- BLI_math_color.h 1828 -> 1783
- BLI_math_vector.hh 496 -> 405
- BLI_index_mask.hh 1341 -> 1267
- BLI_task.hh 958 -> 903
- BLI_generic_virtual_array.hh 509 -> 435
- IMB_colormanagement.h 437 -> 130
- GPU_texture.h 806 -> 780
- FN_multi_function.hh 331 -> 257

Note: DNA_node_tree_interface_types.h needs color include only
for the currently unused (but soon to be used) socket_color function.
Future step is to figure out how to include
DNA_node_tree_interface_types.h less.

Pull Request: #111113
2023-08-16 14:48:53 +03:00
Campbell Barton
e955c94ed3 License Headers: Set copyright to "Blender Authors", add AUTHORS
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.
2023-08-16 00:20:26 +10:00
Jacques Lucke
cc4d5c432c RNA: move headers to C++
Also see #103343.

Pull Request: https://projects.blender.org/blender/blender/pulls/111022
2023-08-10 22:40:27 +02:00
Jacques Lucke
19912457c6 Nodes: use auto registration for nodes
The goal here is to reduce the number of files that need to be edited when
adding a new node. To register a node, one currently has to add a line to
`node_geometry_register.cc` and `node_geometry_register.hh` (for geometry
nodes). Those files can be generated automatically.

There is a new `NOD_REGISTER_NODE` macro that nodes can use to register
themselves. The macro is then discovered by `discover_nodes.py` that generates
code that calls all the registration functions. The script also works when the
register functions are in arbitrary namespaces. This allows simplifying the node
code as well.

In the past I tried a few times to get auto-registration working without resorting to
code generation, but that never ended up working. The general idea for that would
be to use non-trivial initialization for static variables. The issue always ends up
being that the linker just discards those variables, because they are unused and it
doesn't care if there are side effects in the initialization.

Related discussion regarding using Python for code generation:
https://devtalk.blender.org/t/code-generation-with-python/30558

Pull Request: https://projects.blender.org/blender/blender/pulls/110686
2023-08-09 22:01:03 +02:00
Hans Goudey
e3e6fb8ecf Geometry Nodes: Initial tool-specific nodes
Add three new nodes for operations and inputs specific to
node group operators.
- **Selection** Whether elements are selected in the viewport
- **Set Selection** Sets the edit/sculpt selection, on the point,
  face, or curve domains
- **3D Cursor** Gives the location and rotation of the 3D cursor,
  in the local space of the modified object.
- **Face Set** The face set value from mesh sculpt mode,
  and whether the attribute exists.
- **Set Face Set** Set sculpt face set values.

In the add menu and search, the nodes are only visible in the
"Tool" context of the geometry node editor. They also give
errors when executed by a modifier.

Pull Request: https://projects.blender.org/blender/blender/pulls/109517
2023-08-04 20:59:04 +02:00
Hans Goudey
8bb8cfb54e Cleanup: Remove unnecessary struct keyword from C++ headers
Pull Request: https://projects.blender.org/blender/blender/pulls/110734
2023-08-03 01:11:28 +02:00
Jacques Lucke
3d73b71a97 Geometry Nodes: new Repeat Zone
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
2023-07-11 22:36:10 +02:00
Hans Goudey
424c6edc53 Geometry Nodes: Avoid geometry copies in "no cache" simulation
When we don't need to preserve a persistent cache, we can use
the geometry from the last frame directly rather than copying it.
Though implicit lets us avoid copying large data arrays when they
aren't changed, this can still give a large improvement for something
like particle simulation where the majority of the data was copied
every frame.

Pull Request: https://projects.blender.org/blender/blender/pulls/109742
2023-07-11 14:03:12 +02:00
Hans Goudey
e570f13616 Cleanup: Move NOD_geometry.h to C++
Pull Request: https://projects.blender.org/blender/blender/pulls/109306
2023-06-23 22:15:42 +02:00
Sergey Sharybin
c1bc70b711 Cleanup: Add a copyright notice to files and use SPDX format
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/
2023-05-31 16:19:06 +02:00
Jacques Lucke
2cfcb8b0b8 BLI: refactor IndexMask for better performance and memory usage
Goals of this refactor:
* Reduce memory consumption of `IndexMask`. The old `IndexMask` uses an
  `int64_t` for each index which is more than necessary in pretty much all
  practical cases currently. Using `int32_t` might still become limiting
  in the future in case we use this to index e.g. byte buffers larger than
  a few gigabytes. We also don't want to template `IndexMask`, because
  that would cause a split in the "ecosystem", or everything would have to
  be implemented twice or templated.
* Allow for more multi-threading. The old `IndexMask` contains a single
  array. This is generally good but has the problem that it is hard to fill
  from multiple-threads when the final size is not known from the beginning.
  This is commonly the case when e.g. converting an array of bool to an
  index mask. Currently, this kind of code only runs on a single thread.
* Allow for efficient set operations like join, intersect and difference.
  It should be possible to multi-thread those operations.
* It should be possible to iterate over an `IndexMask` very efficiently.
  The most important part of that is to avoid all memory access when iterating
  over continuous ranges. For some core nodes (e.g. math nodes), we generate
  optimized code for the cases of irregular index masks and simple index ranges.

To achieve these goals, a few compromises had to made:
* Slicing of the mask (at specific indices) and random element access is
  `O(log #indices)` now, but with a low constant factor. It should be possible
  to split a mask into n approximately equally sized parts in `O(n)` though,
  making the time per split `O(1)`.
* Using range-based for loops does not work well when iterating over a nested
  data structure like the new `IndexMask`. Therefor, `foreach_*` functions with
  callbacks have to be used. To avoid extra code complexity at the call site,
  the `foreach_*` methods support multi-threading out of the box.

The new data structure splits an `IndexMask` into an arbitrary number of ordered
`IndexMaskSegment`. Each segment can contain at most `2^14 = 16384` indices. The
indices within a segment are stored as `int16_t`. Each segment has an additional
`int64_t` offset which allows storing arbitrary `int64_t` indices. This approach
has the main benefits that segments can be processed/constructed individually on
multiple threads without a serial bottleneck. Also it reduces the memory
requirements significantly.

For more details see comments in `BLI_index_mask.hh`.

I did a few tests to verify that the data structure generally improves
performance and does not cause regressions:
* Our field evaluation benchmarks take about as much as before. This is to be
  expected because we already made sure that e.g. add node evaluation is
  vectorized. The important thing here is to check that changes to the way we
  iterate over the indices still allows for auto-vectorization.
* Memory usage by a mask is about 1/4 of what it was before in the average case.
  That's mainly caused by the switch from `int64_t` to `int16_t` for indices.
  In the worst case, the memory requirements can be larger when there are many
  indices that are very far away. However, when they are far away from each other,
  that indicates that there aren't many indices in total. In common cases, memory
  usage can be way lower than 1/4 of before, because sub-ranges use static memory.
* For some more specific numbers I benchmarked `IndexMask::from_bools` in
  `index_mask_from_selection` on 10.000.000 elements at various probabilities for
  `true` at every index:
  ```
  Probability      Old        New
  0              4.6 ms     0.8 ms
  0.001          5.1 ms     1.3 ms
  0.2            8.4 ms     1.8 ms
  0.5           15.3 ms     3.0 ms
  0.8           20.1 ms     3.0 ms
  0.999         25.1 ms     1.7 ms
  1             13.5 ms     1.1 ms
  ```

Pull Request: https://projects.blender.org/blender/blender/pulls/104629
2023-05-24 18:11:41 +02:00
Damien Picard
0af41365e6 Cleanup: remove translation headers from node files
After 22f641e7f8, translation macros were removed and thus in many
files inclusion of the translation header is no longer needed.

Pull Request: https://projects.blender.org/blender/blender/pulls/107986
2023-05-22 12:05:39 +02:00
Iliya Katueshenock
f7388e3be5 Cleanup: Move BKE_node.h to C++
See: https://projects.blender.org/blender/blender/issues/103343

Changes:
1. Added `BKE_node.hh` file. New file includes old one.
2. Functions moved to new file. Redundant `(void)`, `struct` are removed.
3. All cpp includes replaced from `.h` on `.hh`.
4. Everything in `BKE_node.hh` is on `blender::bke` namespace.
5. All implementation functions moved in namespace.
6. Function names (`BKE_node_*`) changed to `blender::bke::node_*`.
7. `eNodeSizePreset` now is a class, with renamed items.

Pull Request: https://projects.blender.org/blender/blender/pulls/107790
2023-05-15 15:14:22 +02:00
Hans Goudey
d9a7f1285f Cleanup: Rename field input classes to match UI names 2023-05-03 12:10:54 -04:00
Hans Goudey
7f040099e3 Cleanup: Deduplicate sampling at index in geometry nodes
The "Evaluate at Index" and "Sample Index" nodes are exactly the same
once they retrieve the values to copy and the indices (apart from the
clamping option anyway). This also allows devirtualizing the index input
in the evaluate at index node like the sample index node.
2023-05-03 12:10:54 -04:00
Hong Shin
642e18e889 Cleanup: Move node_util.h to C++
Ref: #103343

Pull Request: https://projects.blender.org/blender/blender/pulls/107569
2023-05-03 14:21:14 +02:00
Jacques Lucke
0de54b84c6 Geometry Nodes: add simulation support
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
2023-05-03 13:18:59 +02:00
Jacques Lucke
3ee21d1098 Cleanup: rename anonymous attribute id pointer type 2023-04-21 14:14:27 +02:00
Alexander Revkov
a1f52a02a8 Mesh: Set bounds eagerly for spherical and cylindrical primitive nodes
Eager bounds calculation for cylindrical and spherical primitive nodes,
implemented in constant time rather than as a loop over all positions.
Takes into account the segments count of the circle from which they
are constructed. Solution of the task #105551.

Pull Request: https://projects.blender.org/blender/blender/pulls/105743
2023-03-21 22:38:40 -04:00
Erik Abrahamsson
4b30b5c57f Nodes: SDF Volume nodes milestone 1
Geometry Nodes: SDF Volume nodes milestone 1

Adds initial support for SDF volume creation and manipulation.
`SDF volume` is Blender's name of an OpenVDB grid of type Level Set.
See the discussion about naming in #91668.

The new nodes are:
- Mesh to SDF Volume: Converts a mesh to an SDF Volume
- Points to SDF Volume: Converts points to an SDF Volume
- Mean Filter SDF Volume: Applies a Mean Filter to an SDF
- Offset SDF Volume: Applies an offset to an SDF
- SDF Volume Sphere: Creates an SDF Volume in the shape of a sphere

For now an experimental option `New Volume Nodes` needs to be
enabled in Blender preferences for the nodes to be visible.

See the current work plan for Volume Nodes in #103248.

Pull Request: https://projects.blender.org/blender/blender/pulls/105090
2023-03-19 11:21:08 +01:00
Hans Goudey
111038062a Cleanup: Remove unused node function declarations 2023-03-10 12:26:55 -05:00
Clément Foucault
b0b9e746fa BLI: Use BLI_math_matrix_type.hh instead of BLI_math_float4x4.hh
Straightforward port. I took the oportunity to remove some C vector
functions (ex: copy_v2_v2).

This makes some changes to DRWView to accomodate the alignement
requirements of the float4x4 type.
2023-02-06 21:25:45 +01:00
Ray Molenkamp
b5e00a1482 Revert "BLI: Use BLI_math_matrix_type.hh instead of BLI_math_float4x4.hh"
This reverts commit 52de84b0db.

had some build issues on windows i can't quickly resolve, revert for
now while we fix the problems
2023-02-02 11:46:23 -07:00
Clément Foucault
52de84b0db BLI: Use BLI_math_matrix_type.hh instead of BLI_math_float4x4.hh
Straightforward port. I took the oportunity to remove some C vector
functions (ex: `copy_v2_v2`).

This makes some changes to DRWView to accomodate the alignement
requirements of the float4x4 type.
2023-02-02 18:11:35 +01:00
Hans Goudey
d42d4e339f Cleanup: Remove unnecessary includes in geometry set header 2023-01-17 12:50:06 -06:00