Cycles has a sample offset feature allowing users to render X samples
in a single frame on one device, then the remaining Y samples later or
on a different device and combine them back together at the end.
However in most situations the result from using this method was
different, and usually lower quality than rendering all the samples in
one go.
This was because Cycles tunes it's random number sequence for the
number of samples being rendered. And the random number sequence was
being tuned for the wrong number of samples in the case that a user
was using the sample offset.
This commit fixes this issue by adding a "sample subset" feature.
The user specifies the total sample count being rendered across all
devices in the existing `Max Samples` parameter, then specifies per
device which subset of samples will be rendered (E.g. Render samples
0-1024 out of a 0-2048 range).
This commit also contains some additional clean up work
inside Cycles related to the area being changed.
Co-authored-by: Brecht Van Lommel <brecht@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/132961
Check was misc-const-correctness, combined with readability-isolate-declaration
as suggested by the docs.
Temporarily clang-format "QualifierAlignment: Left" was used to get consistency
with the prevailing order of keywords.
Pull Request: https://projects.blender.org/blender/blender/pulls/132361
* Use .empty() and .data()
* Use nullptr instead of 0
* No else after return
* Simple class member initialization
* Add override for virtual methods
* Include C++ instead of C headers
* Remove some unused includes
* Use default constructors
* Always use braces
* Consistent names in definition and declaration
* Change typedef to using
Pull Request: https://projects.blender.org/blender/blender/pulls/132361
For example
```
OIIOOutputDriver::~OIIOOutputDriver()
{
}
```
becomes
```
OIIOOutputDriver::~OIIOOutputDriver() {}
```
Saves quite some vertical space, which is especially handy for
constructors.
Pull Request: https://projects.blender.org/blender/blender/pulls/105594
Add "stageMetersPerUnit" render setting for USD files that have that set to
something other than the default (e.g. exported by Blender).
And fix a crash when an application creates a Hydra render pass on a thread
that does not have an OpenGL context current.
Long term, this should replace the XML format. This reuses the Hydra render
delegate implementation, and so supports the same features. The same command
line options and GUI work for both XML and USD also.
The implementation of this is still disabled, waiting for some refactoring of
USD library linking. However we want the Cycles code to be in sync between
repositories for the 3.2 release.
Ref T96731
This can be useful to match transforms to what native Cycles
would see in Blender, as USD typically uses centimeters, but
Blender uses meters. This patch also fixes the hardcoded focal
length multiplicator, which is now using the same units as
everything else. Default of "stageMetersPerUnit" is 0.01 to match
the USD default of centimeters.
Differential Revision: https://developer.blender.org/D14630
* Add missing GLEW and hgiGL libraries for Hydra
* Fix wrong case sensitive include
* Fix link errors by adding external libs to static Hydra lib
* Work around weird Hydra link error with MAX_SAMPLES
* Use Embree by default for Hydra
* Sync external libs code with standalone
* Update version number to match Blender
* Remove unneeded CLEW/GLEW from test executable
None of this should affect Cycles in Blender.
Ref T96731
This patch adds a Hydra render delegate to Cycles, allowing Cycles to be used for rendering
in applications that provide a Hydra viewport. The implementation was written from scratch
against Cycles X, for integration into the Blender repository to make it possible to continue
developing it in step with the rest of Cycles. For this purpose it follows the style of the rest of
the Cycles code and can be built with a CMake option
(`WITH_CYCLES_HYDRA_RENDER_DELEGATE=1`) similar to the existing standalone version
of Cycles.
Since Hydra render delegates need to be built against the exact USD version and other
dependencies as the target application is using, this is intended to be built separate from
Blender (`WITH_BLENDER=0` CMake option) and with support for library versions different
from what Blender is using. As such the CMake build scripts for Windows had to be modified
slightly, so that the Cycles Hydra render delegate can e.g. be built with MSVC 2017 again
even though Blender requires MSVC 2019 now, and it's possible to specify custom paths to
the USD SDK etc. The codebase supports building against the latest USD release 22.03 and all
the way back to USD 20.08 (with some limitations).
Reviewed By: brecht, LazyDodo
Differential Revision: https://developer.blender.org/D14398
