Static initialization order was not guaranteed to be correct for node base
types. Now wrap all initialization in accessor functions to ensure the order
is correct.
Did not cause any known bug on Linux/macOS/Windows, but showed up on this
platform.
This type, CacheLookupResult, holds the data for the current time, or an
explanation as to why no data is available (already loaded, or simply
nothing available). This is useful to document the behavior of the code
but also, in future changes, to respond appropriately for missing data.
Inside of the procedural, instances are AlembicObjects which point to
the AlembicObject that they instance.
In Alembic, an instance is an untyped Object pointing to the original
(instanced) one through its source path. During the archive traversal we
detect such instances and, only if the instanced object is asked to be
rendered, set the instance's AlembicObject to point to the original's
AlembicObject.
Cycles Object Nodes are created for each AlembicObject, but only for
non-instances are Geometries created, which are then shared between
Object Nodes. It is supposed, and expected, that all instances share the
same shaders, which will be set to be the ones found on the original
object.
As for caching, the data cache for an AlembicObject is only valid for
non-instances and should not be read to or from as it is implicitly
shared.
This will help support instancing as cache building is now decoupled
from the logic to update the Nodes' sockets as data (and cache) will
need to be shared by different Geometries somehow, and also simplify
implementing different data caching methods by centralizing this
operation.
We need to explicitely tag the Attribute and AttributeSet as modified if
we change or add/remove data. This is more of a bandaid until attributes
handling is refactored to be able to reuse routines from the Attribute
API.
The Blender/Cycles XYZ color space has a D65 white point instead of E, and
this was not correctly accounted for both in the OpenColor config reading code
and the bundled config.
This meant that since the OpenColorIO v2 upgrade, the Linear ACES color space
was not working correctly, and other OpenColorIO configs defining
aces_interchange were not interpreted correctly.
The missing update has two sources:
The TimeSampling used for looking up transformations in the cache was
uninitialized. To fix this, simply use the TimeSampling from the last
transformation in the hierarchy (that is the object's parent), which
should also contain the time information for all of its parents.
The objects are not tagged for update when their trasformations change.
This issue seems to be caused by the reallocation flag not being set on
the device shader data array so it was never updated on the GPU although
the host memory was modified.
When primitive offsets change we need to rebuild or refit BVHs, however this
was also tagging other data as modified too late in the geometry update process.
Now ensure only the BVHs are updated.
Ref D10441
This patch has originally been written by Kévin Dietrich, thanks!
It is part of D10210.
As Brecht noted in D10210, this might not handle all cases yet.
I better solution should come soonish.
Ref T84819
Build System
============
This is an API breaking new version, and the updated code only builds with
OpenColorIO 2.0 and later. Adding backwards compatibility was too complicated.
* Tinyxml was replaced with Expat, adding a new dependency.
* Yaml-cpp is now built as a dependency on Unix, as was already done on Windows.
* Removed currently unused LCMS code.
* Pystring remains built as part of OCIO itself, since it has no good build system.
* Linux and macOS check for the OpenColorIO verison, and disable it if too old.
Ref D10270
Processors and Transforms
=========================
CPU processors now need to be created to do CPU processing. These are cached
internally, but the cache lookup is not fast enough to execute per pixel or
texture sample, so for performance these are now also exposed in the C API.
The C API for transforms will no longer be needed afer all changes, so remove
it to simplify the API and fallback implementation.
Ref D10271
Display Transforms
==================
Needs a bit more manual work constructing the transform. LegacyViewingPipeline
could also have been used, but isn't really any simpler and since it's legacy
we better not rely on it.
We moved more logic into the opencolorio module, to simplify the API. There is
no need to wrap a dozen functions just to be able to do this in C rather than C++.
It's also tightly coupled to the GPU shader logic, and so should be in the same
module.
Ref D10271
GPU Display Shader
==================
To avoid baking exposure and gamma into the GLSL shader and requiring slow
recompiles when tweaking, we manually apply them in the shader. This leads
to some logic duplicaton between the CPU and GPU display processor, but it
seems unavoidable.
Caching was also changed. Previously this was done both on the imbuf and
opencolorio module levels. Now it's all done in the opencolorio module by
simply matching color space names. We no longer use cacheIDs from OpenColorIO
since computing them is expensive, and they are unlikely to match now that
more is baked into the shader code.
Shaders can now use multiple 2D textures, 3D textures and uniforms, rather
than a single 3D texture. So allocating and binding those adds some code.
Color space conversions for blending with overlays is now hardcoded in the
shader. This was using harcoded numbers anyway, if this every becomes a
general OpenColorIO transform it can be changed, but for now there is no
point to add code complexity.
Ref D10273
CIE XYZ
=======
We need standard CIE XYZ values for rendering effects like blackbody emission.
The relation to the scene linear role is based on OpenColorIO configuration.
In OpenColorIO 2.0 configs roles can no longer have the same name as color
spaces, which means our XYZ role and colorspace in the configuration give an
error.
Instead use the new standard aces_interchange role, which relates scene linear
to a known scene referred color space. Compatibility with the old XYZ role is
preserved, if the configuration file has no conflicting names.
Also includes a non-functional change to the configuraton file to use an
XYZ-to-ACES matrix instead of REC709-to-ACES, makes debugging a little easier
since the matrix is the same one we have in the code now and that is also
found easily in the ACES specs.
Ref D10274
This crash is caused by accessing object data in the kernel at an out of bound index from a deleted instance.
Cycles represents instances as Object nodes sharing the same Geometry node, so we need to tag the GeometryManager for an update if some objects are added or removed as no geometry might have been added or removed in order to properly update the BVH and its associated data arrays.
Regression caused by rBbbe6d4492823.
The changes to the socket API were not applied to the standalone app.
Also modify Camera.compute_auto_viewplane() to use Camera.full_width and Camera.full_height as it is not possible to publicly access Camera.width and Camera.height anymore, so the aspect ratio could be computed with stale data.
Differential Revision: https://developer.blender.org/D9961
The implementation is currently optimized to load animation sequences once
and then quickly scrubbing through them. Later on an option should be added
to optimize for memory usage and only load the current frame into memory.
Currently mesh and curve objects are supported, including support for UV and
vertex color attributes. Missing still is support for arbitrary attributes and
motion blur, as well as better handling of changing topology. Shader assignments
are made using FaceSets found in the Alembic archive.
The animation (and constant) data of the objects inside the Alembic archive is
loaded at once at the beginning of the render and kept inside a cache. At each
frame change we simply update the right socket of the corresponding Cycles node
if the data is animated. This allows for fast playback in the viewport
(depending on the scene size and compute power).
Note this is not yet exposed in the Blender UI, it's a feature that is still under
development and not ready for general use.
Ref T79174, D3089
Procedurals are nodes in the scene that can generate an arbitrary number of
other nodes at render time. This will be used to implement an Alembic procedural
that can load an Alembic file into Cycles nodes. In the future we also expect to
have a USD procedural.
Direct loading of such files at render time is a standard feature in other
production renderers. Reasons to support this are memory usage and performance,
delayed loading of heavy scene data until rendering, Cycles standalone rendering
using standard file formats beyond our XML files, and shared functionality for
Cycles integration in multiple 3D apps.
Ref T79174, D3089
Modifications to triangle shader association were not considered when checking for updates and the associated device data array was not tagged as modified so it was not resent to the device(s).
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
Branched path tracing is not supported for OptiX, and it would still use the
number of AA samples from there when branched path was enabled by the user
earlier but auto disabled and hidden in the UI when using OptiX.
Ref D10159
