When enabled, this normalize the strength by the light area, to keep
the total output the same regardless of shape or size. This is the
existing behavior.
This is supported in Cycles, EEVEE, Hydra, USD, COLLADA.
For add-ons, an API function to compute the area is added for conversion,
in case there is no native support for normalization.
area = light.area(matrix_world=ob.matrix_world)
Co-authored-by: Brecht Van Lommel <brecht@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/136958
Similar to other renderers, this adds a temperature property to set the
light color using blackbody emission. This can be more convenient than
using nodes, and can improve interop with other software.
This is supported in Cycles, EEVEE, Hydra, USD, COLLADA and FBX.
Pull Request: https://projects.blender.org/blender/blender/pulls/134303
Similar to other renderers, this adds an exposure property to multiply
the light power by 2^exposure. This can be more convenient to control
a wide range of values.
This is supported in Cycles, EEVEE, Hydra, USD, COLLADA and FBX.
Pull Request: https://projects.blender.org/blender/blender/pulls/134528
It would both set the dome light color and export a texture with that
same color, which would double up. It was also using the World.exposure
member which is not used anywhere else in Blender.
Pull Request: https://projects.blender.org/blender/blender/pulls/134411
Use BLI_uniquename_cb to check and fix naming conflicts, and keep track
of the potentially modified node names in a map.
Reserve the material name, so that later the output node can be renamed to it
without conflicts. Also make sure there are no conflicts with names auto
generated by MaterialX, by always naming nodes ourselves.
Pull Request: https://projects.blender.org/blender/blender/pulls/133234
The new description for `bNode.type_legacy`:
```
/**
* Legacy integer type for nodes. It does not uniquely identify a node type, only the `idname`
* does that. For example, all custom nodes use #NODE_CUSTOM but do have different idnames.
* This is mainly kept for compatibility reasons.
*
* Currently, this type is also used in many parts of Blender, but that should slowly be phased
* out by either relying on idnames, accessor methods like `node.is_reroute()`.
*
* A main benefit of this integer type over using idnames currently is that integer comparison is
* much cheaper than string comparison, especially if many idnames have the same prefix (e.g.
* "GeometryNode"). Eventually, we could introduce cheap-to-compare runtime identifier for node
* types. That could mean e.g. using `ustring` for idnames (where string comparison is just
* pointer comparison), or using a run-time generated integer that is automatically assigned when
* node types are registered.
*/
```
Pull Request: https://projects.blender.org/blender/blender/pulls/132858
NOTE: This also required some changes to Cycles code itself, who is now
directly including `BKE_image.hh` instead of declaring a few prototypes
of these functions in its `blender/utils.h` header (due to C++ functions
names mangling, this was not working anymore).
Pull Request: https://projects.blender.org/blender/blender/pulls/130174
When attempting to cache a generated image, the ImageFormatData's
view_settings would inadvertently be leaked due to the settings being
assigned a different set of values without first being free'd.
Additionally, there was another missed free from an early return a bit
later in the same function.
Pull Request: https://projects.blender.org/blender/blender/pulls/128229
When using the USD export method with Hydra storm[1], problems can occur
because of how this was integrated alongside the direct Hydra method.
The direct hydra support was initially added in Blender 4.0 and the USD
option was integrated at the same time in order to provide a mechanism
for comparison and double-checking each implementation.
In the context of this bug, for Viewport previews and renders, the Hydra
engine is initially triggered and executed as part of an "engine update"
call from the various v3d draw managers. During this call the USD export
is attempted.
For sub-d meshes the USD export machinery will, by default, attempt to
apply the correct Subdivision Scheme attribute to mesh data. That means
it will export the unsubdivided base mesh with an attribute letting the
downstream receiver of the data know they should do the subdivision on
their own. This subdivision scheme support was added in 4.1.
However, in order to do this, USD must first disable the Subdivision
modifiers in Blender before exporting the mesh. Disabling modifiers
triggers depsgraph processing and, unfortunately, this processing will
also trigger an "engine update" for Hydra... again.
Reentrancy is not supported here. See stack trace in original bug.
So, instead, change the USD export option to output a subdivided mesh to
begin with. This has the following ramifications:
- Viewport material preview and render modes no longer crash when sub-d
is used
- While F12/final renders did not crash, changing this option will now
properly render the subdivided geometry when using the USD export
method. Allowing our USD / Hydra render tests to align more closely.
The direct Hydra option was already pre-subdividing mesh data anyhow.
This will require updating the USD reference render images.
- The underlying integration issue is not fixed. Triggering a USD export
inside the "engine update" call path seems error-prone and can lead to
similar issues in the future.
Pull Request: https://projects.blender.org/blender/blender/pulls/125840
This commit moves generated `RNA_blender.h`, `RNA_prototype.h` and
`RNA_blender_cpp.h` headers to become C++ header files.
It also removes the now useless `RNA_EXTERN_C` defines, and just
directly use the `extern` keyword. We do not need anymore `extern "C"`
declarations here.
Pull Request: https://projects.blender.org/blender/blender/pulls/124469
Prevent crash from a mesh created around the time of Blender 4.0 with
bad (negative) material indices on some faces.
The Poly Haven folks were poked to fix the actual asset as well but it's
simple enough for us to clamp in this code path, especially since we
were already doing it for the upper bound.
Pull Request: https://projects.blender.org/blender/blender/pulls/124026
This was previously attempted in #109518 and reverted in #112234. Now do
both the changes in the mesh and material export, and make it an option
in USD export. Hydra always renamed to "st" and continues to do it.
Fix#122800: Missing textures with MaterialX materials
Pull Request: https://projects.blender.org/blender/blender/pulls/123326
This change adds the ability to export MaterialX networks into the resulting
USD layer.
Details:
A new export option has been added to the USD export to enable MaterialX
export. It is off by default currently due to reasons in the caveats
section.
When enabled, it exports the MaterialX shading network alongside the
UsdPreviewSurface network, on the same USD Material. This allows the same
material to be used by renderers that don't support MaterialX, using the
USDPreviewSurface as a fallback. This is similar to setups in other DCC
packages, and matches the format we've used in our Reality Composer Pro
asset library.
It uses the existing MaterialX framework used to generate MaterialX
documents for rendering, to act as the basis for the USD graph. In this
process it also re-uses the existing texture export code as well if provided
and necessary.
Once the MaterialX document is created, use usdMtlx to generate a USD
shading network. Unfortunately, usdMtlx generates a graph that is unlike
what other DCCs that support MaterialX-embedded-in-USD generates. It
generates several extra prim hierarchies, and externalizes all shader
inputs, making them difficult to edit in other MaterialX graph editors.
To workaround this, generate the MaterialX shading network onto a
temporary stage, where we then run various pre-processing steps to prevent
prim collisions and to reflow the paths once they're converted.
The PrimSpecs are then copied over to their new path. The resulting prim
hierarchy matches what many artists we've worked with prefer to work with.
Caveats:
The Export MaterialX check is off by default. When using the Principled
BSDF, the resulting graph is very usable. However, when using some of the
other BSDFs, the shading networks generated by the existing MaterialX
framework in Blender generate some shading graphs that are difficult for
usdview and other DCC's to understand. The graph is still correct, but
because we're trying to prioritize compatibility, the default is off.
In future PRs we can aim to make the graphs for those other BSDFs play
better with other DCCs.
Other Implementation Details:
As part of this commit we've also done the following:
* Place some of the materialx graphs inside a passthrough nodegraph to
avoid node conflicts.
* Better handle some shader output types , and better handle some
conflict cases.
* Moved the ExportTextureFunction to materials.h due to some difficult
to resolve header ordering issues. This has no effect on any runtime code.
* There is a test for the MaterialX export that does some basic checking to
make sure we get an export out the other end that matches our expectations
Authored by Apple: Dhruv Govil
This PR is based on an earlier implementation by Brecht van Lommel , as well
as Brian Savery and his teams' work at AMD to implement the general
MaterialX framework within Blender.
Pull Request: https://projects.blender.org/blender/blender/pulls/122575
The depsgraph CoW mechanism is a bit of a misnomer. It creates an
evaluated copy for data-blocks regardless of whether the copy will
actually be written to. The point is to have physical separation between
original and evaluated data. This is in contrast to the commonly used
performance improvement of keeping a user count and copying data
implicitly when it needs to be changed. In Blender code we call this
"implicit sharing" instead. Importantly, the dependency graph has no
idea about the _actual_ CoW behavior in Blender.
Renaming this functionality in the despgraph removes some of the
confusion that comes up when talking about this, and will hopefully
make the depsgraph less confusing to understand initially too. Wording
like "the evaluated copy" (as opposed to the original data-block) has
also become common anyway.
Pull Request: https://projects.blender.org/blender/blender/pulls/118338
The `object_to_world` and `world_to_object` matrices are set during
depsgraph evaluation, calculated from the object's animated location,
rotation, scale, parenting, and constraints. It's confusing and
unnecessary to store them with the original data in DNA.
This commit moves them to `ObjectRuntime` and moves the matrices to
use the C++ `float4x4` type, giving the potential for simplified code
using the C++ abstractions. The matrices are accessible with functions
on `Object` directly since they are used so commonly. Though for write
access, directly using the runtime struct is necessary.
The inverse `world_to_object` matrix is often calculated before it's
used, even though it's calculated as part of depsgraph evaluation.
Long term we might not want to store this in `ObjectRuntime` at all,
and just calculate it on demand. Or at least we should remove the
redundant calculations. That should be done separately though.
Pull Request: https://projects.blender.org/blender/blender/pulls/118210
This header is for 'internal' USD code only (also needed by the hydra
code), and uses references to the USD library itself, so its previous
name was a bit too generic.
First step to move the main public Blender USD API header (`usd.h`) to cpp.
The same is done for other geometry types. This allows us to use C++ types in
the run-time data more easily and avoids dumping runtime data into .blend files.
Pull Request: https://projects.blender.org/blender/blender/pulls/116840
Some common headers were including this. Separating the includes
will ideally lead to better conceptual separation between CustomData
and the attribute API too. Mostly the change is adding the file to
places where it was included indirectly before. But some code is
shuffled around to hopefully better places as well.
Remove most includes of this header inside other headers, to remove unnecessary
indirect includes which can have a impact on compile times. In the future we may
want more dedicated "_fwd.hh" headers, but until then, this sticks with the
solution in existing code.
Unfortunately it isn't yet possible to remove the include from `BKE_geometry_set.hh`.
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.
This refactors how volume grids are stored with the following new goals in mind:
* Get a **stand-alone volume grid** data structure that can be used by geometry nodes.
Previously, the `VolumeGrid` data structure was tightly coupled with the `Volume` data block.
* Support **implicit sharing of grids and trees**. Previously, it was possible to share data
when multiple `Volume` data blocks loaded grids from the same `.vdb` files but this was
not flexible enough.
* Get a safe API for **lazy-loading and unloading** of grids without requiring explicit calls
to some "load" function all the time.
* Get a safe API for **caching grids from files** that is not coupled to the `Volume` data block.
* Get a **tiered API** for different levels of `openvdb` involvement:
* No `OpenVDB`: Since `WITH_OPENVDB` is optional, it's helpful to have parts of the API that
still work in this case. This makes it possible to write high level code for volumes that does
not require `#ifdef WITH_OPENVDB` checks everywhere. This is in `BKE_volume_grid_fwd.hh`.
* Shallow `OpenVDB`: Code using this API requires `WITH_OPENVDB` checks. However, care
is taken to not include the expensive parts of `OpenVDB` and to use forward declarations as
much as possible. This is in `BKE_volume_grid.hh` and uses `openvdb_fwd.hh`.
* "Full" `OpenVDB`: This API requires more heavy `OpenVDB` includes. Fortunately, it turned
out to be not necessary for the common API. So this is only used for task specific APIs.
At the core of the new API is the `VolumeGridData` type. It's a wrapper around an
`openvdb::Grid` and adds some features on top like implicit sharing, lazy-loading and unloading.
Then there are `GVolumeGrid` and `VolumeGrid` which are containers for a volume grid.
Semantically, each `VolumeGrid` has its own independent grid, but this is cheap due to implicit
sharing. At highest level we currently have the `Volume` data-block which contains a list of
`VolumeGrid`.
```mermaid
flowchart LR
Volume --> VolumeGrid --> VolumeGridData --> openvdb::Grid
```
The loading of `.vdb` files is abstracted away behind the volume file cache API. This API makes
it easy to load and reuse entire files and individual grids from disk. It also supports caching
simplify levels for grids on disk.
An important new concept are the "tree access tokens". Whenever some code wants to work
with an openvdb tree, it has to retrieve an access token from the corresponding `VolumeGridData`.
This access token has to be kept alive for as long as the code works with the grid data. The same
token is valid for read and write access. The purpose of these access tokens is to make it possible
to detect when some code is currently working with the openvdb tree. This allows freeing it if it's
possible to reload it later on (e.g. from disk). It's possible to free a tree that is referenced by
multiple owners, but only no one is actively working with. In some sense, this is similar to the
existing `ImageUser` concept.
The most important new files to read are `BKE_volume_grid.hh` and `BKE_volume_grid_file_cache.hh`.
Most other changes are updates to existing code to use the new API.
Pull Request: https://projects.blender.org/blender/blender/pulls/116315
