This patch ports the GLSL SMAA library to the CPU compositor in order to
unify the anti-aliasing behavior between the CPU and GPU compositor.
Additionally, the SMAA texture generator was removed since it is now
unused.
Previously, we used an external C++ library for SMAA anti-aliasing,
which is itself a port of the GLSL SMAA library. However, the code
structure and results of the library were different, which made it quite
difficult to match results between CPU and GPU, hence the decision to
port the library ourselves.
The port was performed through a complete copy of the library to C++,
retaining the same function and variable names, even if they are
different from Blender's naming conversions. The necessary code changes
were done to make it work in C++, including manually doing swizzling
which changes the code structure a bit.
Even after porting the library, there were still major differences
between CPU and GPU, due to different arithmetic precision. To fix this
some of the bilinear samplers used in branches and selections were
carefully changed to use point samplers to avoid discontinuities around
branches, also resulting in a nice performance improvement. Some slight
differences still exist due to different bilinear interpolation, but
they shall be looked into later once we have a baseline implementation.
The new implementation is slower than the existing implementation, most
likely due to the liberal use of bilinear interpolation, since it is
quite cheap on GPUs and the code even does more work to use bilinear
interpolation to avoid multiple texture fetches, except this causes a
slow down on CPUs. Some of those were alleviated as mentioned in the
previous section, but we can probably look into optimizing it further.
Pull Request: https://projects.blender.org/blender/blender/pulls/119414
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.
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/
Push the const usage a bit further for compositor nodes, so that they
are more explicit about not modifying original nodes from the editor.
Differential Revision: https://developer.blender.org/D15822
Use a shorter/simpler license convention, stops the header taking so
much space.
Follow the SPDX license specification: https://spdx.org/licenses
- C/C++/objc/objc++
- Python
- Shell Scripts
- CMake, GNUmakefile
While most of the source tree has been included
- `./extern/` was left out.
- `./intern/cycles` & `./intern/atomic` are also excluded because they
use different header conventions.
doc/license/SPDX-license-identifiers.txt has been added to list SPDX all
used identifiers.
See P2788 for the script that automated these edits.
Reviewed By: brecht, mont29, sergey
Ref D14069
Order copyright immediately after the license block,
this was done almost everywhere with a few exceptions.
Remove authors from a few files (we had already removed "Contributors"
section however with old patches being applied this gets added back in).
Also move descriptive text into the doxygen comment block under \file.
In some cases remove the text as it was accidentally copied.
This is an implementation of Enhanced Subpixel Morphological Antialiasing (SMAA)
The algorithm was proposed by:
Jorge Jimenez, Jose I. Echevarria, Tiago Sousa, Diego Gutierrez
This node provides only SMAA 1x mode, so the operation will be done with no spatial
multisampling nor temporal supersampling. See Patch for comparisons.
The existing AA operation seems to be used only for binary images by some other nodes.
Using SMAA for binary images needs no important parameter such as "threshold", so we
perhaps can switch the operation to SMAA, though that changes existing behavior.
Notes:
1. The program code assumes the screen coordinates are DirectX style that the
vertical direction is upside-down, so "top" and "bottom" actually represent bottom
and top, respectively.
Thanks for Habib Gahbiche (zazizizou) to polish and finalize this patch.
Reviewed By: jbakker
Differential Revision: https://developer.blender.org/D2411
Omar Emara
Campbell Barton
Sergey Sharybin
Hans Goudey
Manuel Castilla
Jeroen Bakker
Habib Gahbiche