Previously fluid simulation and Alembic modifiers had a dedicated function
to query the velocity for motion blur. Now use a more generic system where
those modifiers output a velocity attribute.
Advantages:
* Geometry and particle nodes can output velocity through the same mechanism,
or read the attribute coming from earlier modifiers.
* The velocity can be preserved through modifiers like subdivision surface or
auto smooth.
* USD and Alembic previously only output velocity from fluid simulation, now
they work with velocity from other sources too.
* Simplifies the code for renderers like Cycles and exporters like
Alembic and USD.
This breaks compatibility:
* External renderers and exporters accessing these velocities through the
Python API now need to use the attribute instead.
* Existing modifier node setups that create an attribute named "velocity"
will render differently with motion blur.
Differential Revision: https://developer.blender.org/D12305
Previously, the Point Instance node in geometry nodes could only instance
existing objects or collections. The reason was that large parts of Blender
worked under the assumption that objects are the main unit of instancing.
Now we also want to instance geometry within an object, so a slightly larger
refactor was necessary.
This should not affect files that do not use the new kind of instances.
The main change is a redefinition of what "instanced data" is. Now, an
instances is a cow-object + object-data (the geometry). This can be nicely
seen in `struct DupliObject`. This allows the same object to generate
multiple geometries of different types which can be instanced individually.
A nice side effect of this refactor is that having multiple geometry components
is not a special case in the depsgraph object iterator anymore, because those
components are integrated with the `DupliObject` system.
Unfortunately, different systems that work with instances in Blender (e.g.
render engines and exporters) often work under the assumption that objects are
the main unit of instancing. So those have to be updated as well to be able to
handle the new instances. This patch updates Cycles, EEVEE and other viewport
engines. Exporters have not been updated yet. Some minimal (not master-ready)
changes to update the obj and alembic exporters can be found in P2336 and P2335.
Different file formats may want to handle these new instances in different ways.
For users, the only thing that changed is that the Point Instance node now
has a geometry mode.
This also fixes T88454.
Differential Revision: https://developer.blender.org/D11841
As subdivision objects are first class citizens in Alembic, to
differentiate them with non-subdivided polygon meshes, the Alembic
Procedural automatically sets up subdivision properties on the generated
Cycles Mesh.
However, for real-time playback subdivision is far too slow, so this
modifies the detection of a MeshSeqCache modifier used to activate the
procedural to allow for a Subsurf modifier right after the cache one. If
present, the procedural will tag the object for subdivision, if absent, the
object will be treated as a regular mesh.
This is a temporary measure for until subdivision surface settings are part
of the Mesh datablock (see T68891).
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D11162
This patch exposes the Cycles Alembic Procedural through the MeshSequenceCache
modifier in order to use and test it from Blender.
To enable it, one has to switch the render feature set to experimental and
activate the Procedural in the modifier. An Alembic Procedural is then
created for each CacheFile from Blender set to use the Procedural, and each
Blender object having a MeshSequenceCache modifier is added to list of objects
of the right procedural.
The procedural's parameters derive from the CacheFile's properties which are
already exposed in the UI through the modifier, although more Cycles specific
options might be added in the future.
As there is currently no cache controls and since we load all the data at the
beginning of the render session, the procedural is only available during
viewport renders at the moment. When an Alembic procedural is rendered, data
from the archive are not read on the Blender side.
If a Cycles render is not active and the CacheFile is set to use the Cycles Procedural,
bounding boxes are used to display the objects in the scene as a signal that the
objects are not processed by Blender anymore. This is standard in other DCCs.
However this does not reduce the memory usage from Blender as the Alembic data
was already loaded either during an import or during a .blend file read.
This is mostly a hack to test the Cycles Alembic procedural until we have a
better Blender side mechanism for letting renderers load their own geometry,
which will be based on import and export settings on Collections (T68933).
Ref T79174, D3089
Reviewed By: brecht, sybren
Maniphest Tasks: T79174
Differential Revision: https://developer.blender.org/D10197
Motion attributes expects mesh to have non-zero number of motion steps,
which was violated in the case when fluid mesh had motion blur disabled.
This is a bit of annoying fix, because of the order of updates. More
ideal solution would be to handle cached and fluid velocities in the
sync_mesh_motion() which ensures all the dependencies between settings.
This patch renames two domains:
* `Polygon` -> `Face`
* `Corner` -> `Face Corner`
For the change from `polygon` to `face` I did a "deep rename" where I updated
all (most?) cases where we refere to the attribute domain in code as well.
The change from `corner` to `face corner` is only a ui change. I did not see
a real need to update all code the code for that. It does not seem to improve
the code, more on the contrary.
Ref T86818.
Differential Revision: https://developer.blender.org/D10803
This makes custom mesh attributes available in Cycles. Typically,
these attributes are generated by Geometry Nodes, but they can also
be created with a Python script.
* The `subdivision` code path is not yet supported.
* This does not make vertex weights and some other builtin attributes
available in Cycles, even though they are accesible in Geometry Nodes.
All attributes generated in Geometry Nodes should be accessible though.
* In some cases memory consumption could be removed by not storing all
attributes in floats. E.g. booleans and integer attributes for which
all values are within a certain range, could be stored in less than
4 bytes per element.
Differential Revision: https://developer.blender.org/D10210
Using rna iterators in range-based for loops is possible since {rBc4286ddb095d32714c9d5f10751a14f5871b3844}.
This patch only updates the places that are easy to update
without more changes in surrounding code.
Differential Revision: https://developer.blender.org/D10195
This optimizes device updates (during user edits or frame changes in
the viewport) by avoiding unnecessary computations. To achieve this,
we use a combination of the sockets' update flags as well as some new
flags passed to the various managers when tagging for an update to tell
exactly what the tagging is for (e.g. shader was modified, object was
removed, etc.).
Besides avoiding recomputations, we also avoid resending to the devices
unmodified data arrays, thus reducing bandwidth usage. For OptiX and
Embree, BVH packing was also multithreaded.
The performance improvements may vary depending on the used device (CPU
or GPU), and the content of the scene. Simple scenes (e.g. with no adaptive
subdivision or volumes) rendered using OptiX will benefit from this work
the most.
On average, for a variety of animated scenes, this gives a 3x speedup.
Reviewed By: #cycles, brecht
Maniphest Tasks: T79174
Differential Revision: https://developer.blender.org/D9555
The issue is caused by stale data on the Mesh Node which is not cleared
during synchronizing since the socket API refactor so that we can detect
changes. However, synchronization only updates the sockets of the Mesh,
so other properties were left with outdated values.
This caused an underflow when computing attribute size for undisplaced
coordinates as it was using the current number of vertices minus the
previous count of subdivision vertices, which at this point should be 0.
Added a simple method to clear non socket data. Also modified
Mesh.add_undisplaced to always use an ATTR_PRIM_GEOMETRY as the data is
not subdivided yet and it avoids any further issues regarding computing
attribute sizes.
The issue is that the shaders are stolen from the original Geometry by
the temporary Geometry used to accumulate data, but the main thread
still needs them for syncing the attributes.
So make a copy of the shader array to preserve the data on the original
Geometry.
This encapsulates Node socket members behind a set of specific methods;
as such it is no longer possible to directly access Node class members
from exporters and parts of Cycles.
The methods are defined via the NODE_SOCKET_API macros in `graph/
node.h`, and are for getting or setting a specific socket's value, as
well as querying or modifying the state of its update flag.
The setters will check whether the value has changed and tag the socket
as modified appropriately. This will let us know how a Node has changed
and what to update, which is the first concrete step toward a more
granular scene update system.
Since the setters will tag the Node sockets as modified when passed
different data, this patch also removes the various modified methods
on Nodes in favor of Node::is_modified which checks the sockets'
update flags status.
Reviewed By: brecht
Maniphest Tasks: T79174
Differential Revision: https://developer.blender.org/D8544
Uniform attributes require immediate access to the shader list
in object update code, so setting the field can't be deferred
to a background task. This required adding a parameter to the
clear method of Geometry.
Ref D2057
This encapsulates Node socket members behind a set of specific methods;
as such it is no longer possible to directly access Node class members
from exporters and parts of Cycles.
The methods are defined via the NODE_SOCKET_API macros in `graph/
node.h`, and are for getting or setting a specific socket's value, as
well as querying or modifying the state of its update flag.
The setters will check whether the value has changed and tag the socket
as modified appropriately. This will let us know how a Node has changed
and what to update, which is the first concrete step toward a more
granular scene update system.
Since the setters will tag the Node sockets as modified when passed
different data, this patch also removes the various `modified` methods
on Nodes in favor of `Node::is_modified` which checks the sockets'
update flags status.
Reviewed By: brecht
Maniphest Tasks: T79174
Differential Revision: https://developer.blender.org/D8544
The problem occurs when a deforming modifier is added to the object
after the MeshSequenceCache modifier. We should only consider the cached
velocities if the MeshSequenceCache modifier is the last one on the
object and we also need to check for the correct vertex count before
adding the motion vertex attribute.
This patch adds the ability to render motion blur from Alembic caches.
The motion blur data is derived from a velocity attribute whose name has
to be defined by the user through the MeshSequenceCache modifier, with a
default value of ".velocities", which is the standard name in Alembic
for the velocity property, although other software may ignore it and
write velocity with their own naming convention (e.g. "v" in Houdini).
Furthermore, a property was added to define how the velocity vectors
are interpreted with regard to time : frame or second. "Frame"
means that the velocity is already scaled by the time step and we do not
need to modify it for it to look proper. "Second" means that the unit
the velocity was measured in is in seconds and so has to be scaled by
some time step computed here as being the time between two frames (1 /
FPS, which would be typical for a simulation). This appears to be
common, and is the default behavior.
Another property was added to control the scale of the velocity to
further modify the look of the motion blur.
Reviewed By: brecht, sybren
Differential Revision: https://developer.blender.org/D2388
The node would render black in this case (but should use the
'active_render' layer choosen in the object data properties -- this is
now in line to how this is handled for e.g. UVs)
This introduces ATTR_STD_VERTEX_COLOR and uses this thoughout, if no
particular layer is specified in the node.
Maniphest Tasks: T73938
Differential Revision: https://developer.blender.org/D6887
A collection of smaller changes that are required in the /blender/source files. A lot of them are also due to variable renaming.
Reviewed By: sergey
Maniphest Tasks: T59995
Differential Revision: https://developer.blender.org/D3855
The Random Per Island attribute is a random float associated with each
connected component (island) of the mesh. It is particularly useful
when artists want to add variations to meshes composed of separate
units. Like tree leaves created using particle systems, wood planks
created using array modifiers, or abstract splines created using AN.
Reviewed By: Sergey Sharybin, Jacques Lucke
Differential Revision: https://developer.blender.org/D6154
This patch adds a new Vertex Color node. The node also returns the alpha
of the vertex color layer as an output.
Reviewers: brecht
Differential Revision: https://developer.blender.org/D5767
This could happen e.g. when changing smoke type from flow to domain or
connecting a volume shader with to a domain without an actual flow type
around.
Fixes T58569, T68359
Reviewers: brecht
Maniphest Tasks: T58569, T68359
Differential Revision: https://developer.blender.org/D5478
This also replaces the Use Alpha setting. We now have these alpha modes:
* Straight: store RGB and alpha channels separately with alpha acting as a
mask, also known as unassociated alpha.
* Premultiplied: transparent RGB pixels are multiplied by the alpha channel.
The natural format for renders.
* Channel Packed: different images are packed in the RGB and alpha channels,
and they should not influence each other. Channel packing is commonly used
by game engines to save memory.
* None: ignore alpha channel from the file and make image fully opaque.
Cycles OSL does not correctly support Channel Packed and None yet, we are
missing fine control over the OpenImageIO texture cache to do that.
Fixes T53672
These are the internal changes to Cycles, for Blender integration there are no
functional changes in this commit.
Images are converted to scene linear color space on file load, and on reading
from the OpenImageIO texture cache. 8-bit images are compressed with the sRGB
transfer function to avoid precision loss while keeping memory usages low. This
also means that for common cases of 8-bit sRGB images no conversion happens at
all on image loading.
Initial patch by Lukas, completed by Brecht.
Differential Revision: https://developer.blender.org/D3491
Do it only for meshes/curves since those are potentially slow and need user
feedback to see things are not stuck. For object instances and lights assume
it's fast enough.
Printing too much can have a performance impact on slow Windows command
prompt or when logging complex scene renders.
