Commit Graph

54 Commits

Author SHA1 Message Date
Andrii Symkin
d832d993c5 Cycles: add new Spectrum and PackedSpectrum types
These replace float3 and packed_float3 in various places in the kernel where a
spectral color representation will be used in the future. That representation
will require more than 3 channels and conversion to from/RGB. The kernel code
was refactored to remove the assumption that Spectrum and RGB colors are the
same thing.

There are no functional changes, Spectrum is still a float3 and the conversion
functions are no-ops.

Differential Revision: https://developer.blender.org/D15535
2022-08-09 16:49:34 +02:00
Brecht Van Lommel
9cfc7967dd Cycles: use SPDX license headers
* Replace license text in headers with SPDX identifiers.
* Remove specific license info from outdated readme.txt, instead leave details
  to the source files.
* Add list of SPDX license identifiers used, and corresponding license texts.
* Update copyright dates while we're at it.

Ref D14069, T95597
2022-02-11 17:47:34 +01:00
Michael Jones
a0f269f682 Cycles: Kernel address space changes for MSL
This is the first of a sequence of changes to support compiling Cycles kernels as MSL (Metal Shading Language) in preparation for a Metal GPU device implementation.

MSL requires that all pointer types be declared with explicit address space attributes (device, thread, etc...). There is already precedent for this with Cycles' address space macros (ccl_global, ccl_private, etc...), therefore the first step of MSL-enablement is to apply these consistently. Line-for-line this represents the largest change required to enable MSL. Applying this change first will simplify future patches as well as offering the emergent benefit of enhanced descriptiveness.

The vast majority of deltas in this patch fall into one of two cases:

- Ensuring ccl_private is specified for thread-local pointer types
- Ensuring ccl_global is specified for device-wide pointer types

Additionally, the ccl_addr_space qualifier can be removed. Prior to Cycles X, ccl_addr_space was used as a context-dependent address space qualifier, but now it is either redundant (e.g. in struct typedefs), or can be replaced by ccl_global in the case of pointer types. Associated function variants (e.g. lcg_step_float_addrspace) are also redundant.

In cases where address space qualifiers are chained with "const", this patch places the address space qualifier first. The rationale for this is that the choice of address space is likely to have the greater impact on runtime performance and overall architecture.

The final part of this patch is the addition of a metal/compat.h header. This is partially complete and will be extended in future patches, paving the way for the full Metal implementation.

Ref T92212

Reviewed By: brecht

Maniphest Tasks: T92212

Differential Revision: https://developer.blender.org/D12864
2021-10-14 16:14:43 +01:00
Campbell Barton
c1c6c11ca6 Cleanup: spelling in comments 2021-10-12 17:55:02 +11:00
Brecht Van Lommel
a94343a8af Cycles: improve SSS Fresnel and retro-reflection in Principled BSDF
For details see the "Extending the Disney BRDF to a BSDF with Integrated
Subsurface Scattering" paper.

We split the diffuse BSDF into a lambertian and retro-reflection component.
The retro-reflection component is always handled as a BSDF, while the
lambertian component can be replaced by a BSSRDF.

For the BSSRDF case, we compute Fresnel separately at the entry and exit
points, which may have different normals. As the scattering radius decreases
this converges to the BSDF case.

A downside is that this increases noise for subsurface scattering in the
Principled BSDF, due to some samples going to the retro-reflection component.
However the previous logic (also in 2.93) was simple wrong, using a
non-sensical view direction vector at the exit point. We use an importance
sampling weight estimate for the retro-reflection to try to better balance
samples between the BSDF and BSSRDF.

Differential Revision: https://developer.blender.org/D12801
2021-10-11 18:22:54 +02:00
Brecht Van Lommel
73a05ff9e8 Cycles: restore Christensen-Burley SSS
There is not enough time before the release to improve Random Walk to handle
all cases this was used for, so restore it for now.

Since there is no more path splitting in cycles-x, this can increase noise in
non-flat areas for the sample number of samples, though fewer rays will be traced
also. This is fundamentally a trade-off we made in the new design and why Random
Walk is a better fit. However the importance resampling we do now does help to
reduce noise.

Differential Revision: https://developer.blender.org/D12800
2021-10-11 18:22:54 +02:00
Campbell Barton
4d66cbd140 Cleanup: spelling in comments 2021-09-22 14:54:01 +10:00
Brecht Van Lommel
0803119725 Cycles: merge of cycles-x branch, a major update to the renderer
This includes much improved GPU rendering performance, viewport interactivity,
new shadow catcher, revamped sampling settings, subsurface scattering anisotropy,
new GPU volume sampling, improved PMJ sampling pattern, and more.

Some features have also been removed or changed, breaking backwards compatibility.
Including the removal of the OpenCL backend, for which alternatives are under
development.

Release notes and code docs:
https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Cycles
https://wiki.blender.org/wiki/Source/Render/Cycles

Credits:
* Sergey Sharybin
* Brecht Van Lommel
* Patrick Mours (OptiX backend)
* Christophe Hery (subsurface scattering anisotropy)
* William Leeson (PMJ sampling pattern)
* Alaska (various fixes and tweaks)
* Thomas Dinges (various fixes)

For the full commit history, see the cycles-x branch. This squashes together
all the changes since intermediate changes would often fail building or tests.

Ref T87839, T87837, T87836
Fixes T90734, T89353, T80267, T80267, T77185, T69800
2021-09-21 14:55:54 +02:00
Campbell Barton
93eb460dd0 Cleanup: clang-format (re-run after v12 version bump) 2021-07-30 16:19:19 +10:00
Brecht Van Lommel
b63e6ab8d2 Fix Cycles SSS incorrect rendering of zero radius in green channel
Thanks to pembem22 for finding the problem.

Ref D8949
2020-09-22 16:28:12 +02:00
Campbell Barton
b1959a96a2 Cleanup: spelling 2019-08-18 04:26:34 +10:00
Campbell Barton
6529d20d79 Cleanup: spelling in comments 2019-06-12 09:43:49 +10:00
Brecht Van Lommel
4df66dabb8 Fix T65212: Cycles SSS failing on 32 bit 2019-05-28 18:05:31 +02:00
Campbell Barton
c47d669f24 Cleanup: comments (long lines) in cycles 2019-05-01 21:41:07 +10:00
Campbell Barton
e12c08e8d1 ClangFormat: apply to source, most of intern
Apply clang format as proposed in T53211.

For details on usage and instructions for migrating branches
without conflicts, see:

https://wiki.blender.org/wiki/Tools/ClangFormat
2019-04-17 06:21:24 +02:00
Sergey Sharybin
cb4b5e12ab Cycles: Cleanup, spacing after preprocessor
It is supposed to be two spaces before comment stating which if
else/endif statements corresponds to. Was mainly violated in the
header guards.
2018-11-09 11:34:54 +01:00
Campbell Barton
1daa20ad9f Cleanup: strip trailing space for cycles 2018-07-06 10:17:58 +02:00
Brecht Van Lommel
a6968e87f1 Cycles: add random walk subsurface scattering to Principled BSDF.
Differential Revision: https://developer.blender.org/D3054
2018-02-09 19:58:42 +01:00
Brecht Van Lommel
0df9b2c715 Cycles: random walk subsurface scattering.
It is basically brute force volume scattering within the mesh, but part
of the SSS code for faster performance. The main difference with actual
volume scattering is that we assume the boundaries are diffuse and that
all lighting is coming through this boundary from outside the volume.

This gives much more accurate results for thin features and low density.
Some challenges remain however:

* Significantly more noisy than BSSRDF. Adding Dwivedi sampling may help
  here, but it's unclear still how much it helps in real world cases.
* Due to this being a volumetric method, geometry like eyes or mouth can
  darken the skin on the outside. We may be able to reduce this effect,
  or users can compensate for it by reducing the scattering radius in
  such areas.
* Sharp corners are quite bright. This matches actual volume rendering
  and results in some other renderers, but maybe not so much real world
  objects.

Differential Revision: https://developer.blender.org/D3054
2018-02-09 19:58:33 +01:00
Brecht Van Lommel
7b29e91711 Code refactor: make mixed small/large BSSRDF radii more robust. 2018-01-26 23:06:53 +01:00
Brecht Van Lommel
ce4915cddb Code refactor: store RGB BSSRDF in a single closure.
Previously we stored each color channel in a single closure, which was
convenient for sampling a closure and channel together. But this doesn't
work so well for algorithms where we want to render multiple color
channels together.
2018-01-26 18:47:21 +01:00
Sergey Sharybin
51e2844387 Cycles: Fix wrong behavior of sharpness in Cubic SSS
Was giving difference when using sharpness of 1.0 and 0.999 even though the
result was expected to be really close to each other.

This SSS profile will probably be removed in the future in favor of more
physically bases Burley, but for the time being don't see anything wrong
fixing an existing code.
2017-11-20 11:40:55 +01:00
Brecht Van Lommel
26f39e6359 Cycles: add bevel shader, for raytrace based rounded edges.
The algorithm averages normals from nearby surfaces. It uses the same
sampling strategy as BSSRDFs, casting rays along the normal and two
orthogonal axes, and combining the samples with MIS.

The main concern here is that we are introducing raytracing inside
shader evaluation, which could be quite bad for GPU performance and
stack memory usage. In practice it doesn't seem so bad though.

Note that using this feature can easily slow down renders 20%, and
that if you care about performance then it's better to use a bevel
modifier. Mainly this is useful for baking, and for cases where the
mesh topology makes it difficult for the bevel modifier to work well.

Differential Revision: https://developer.blender.org/D2803
2017-11-07 22:35:12 +01:00
Brecht Van Lommel
b3afc8917c Code cleanup: refactor BSSRDF closure sampling, for next commit. 2017-09-20 19:38:08 +02:00
Sergey Sharybin
467d92b8f1 Cycles: Tweaks to avoid compilation error of megakernel
Also moved code out of deep-inside ifdef block, otherwise it was quite confusing.
2017-09-12 13:33:46 +05:00
Lukas Stockner
43b374e8c5 Cycles: Implement denoising option for reducing noise in the rendered image
This commit contains the first part of the new Cycles denoising option,
which filters the resulting image using information gathered during rendering
to get rid of noise while preserving visual features as well as possible.

To use the option, enable it in the render layer options. The default settings
fit a wide range of scenes, but the user can tweak individual settings to
control the tradeoff between a noise-free image, image details, and calculation
time.

Note that the denoiser may still change in the future and that some features
are not implemented yet. The most important missing feature is animation
denoising, which uses information from multiple frames at once to produce a
flicker-free and smoother result. These features will be added in the future.

Finally, thanks to all the people who supported this project:

- Google (through the GSoC) and Theory Studios for sponsoring the development
- The authors of the papers I used for implementing the denoiser (more details
  on them will be included in the technical docs)
- The other Cycles devs for feedback on the code, especially Sergey for
  mentoring the GSoC project and Brecht for the code review!
- And of course the users who helped with testing, reported bugs and things
  that could and/or should work better!
2017-05-07 14:40:58 +02:00
Sergey Sharybin
9781139590 Cycles: Solve speed regression of classroom scene after principled commit
This way we can skip it from compiling into OpenCL kernels by making
this shader compile-time feature.
2017-04-21 14:41:42 +02:00
Pascal Schoen
8825a8e951 Squashed commit of the following:
commit 90778901c9ea1e16d5907981e91bceba25ff207d
Merge: 76eebd9 3bf0026
Author: Schoen <schoepas@deher1m1598.emea.adsint.biz>
Date:   Mon Apr 3 07:52:05 2017 +0200

    Merge branch 'master' into cycles_disney_brdf

commit 76eebd9379a5dad519ff01cf215fbe3db6de931e
Author: Schoen <schoepas@deher1m1598.emea.adsint.biz>
Date:   Thu Mar 30 15:34:20 2017 +0200

    Updated copyright for the new files.

commit 013f4a152a3898946ba5c616141c6e44d928ccfd
Author: Schoen <schoepas@deher1m1598.emea.adsint.biz>
Date:   Thu Mar 30 15:32:55 2017 +0200

    Switched from multiplication of base and subsurface color to blending
    between them using the subsurface parameter.

commit 482ec5d1f20ceabc9cbda4838d4ae37d1d673458
Author: Schoen <schoepas@deher1m1598.emea.adsint.biz>
Date:   Mon Mar 13 15:47:12 2017 +0100

    Fixed a bug that caused an additional white diffuse closure call when using
    path tracing.

commit 26e906d162a6a8d67f2ebc8880993fcbab69559e
Merge: 0593b8c 223aff9
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Feb 6 11:32:31 2017 +0100

    Merge branch 'master' into cycles_disney_brdf

commit 0593b8c51bf7db0ed5ca92ed6f68d0d984dad0dd
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Feb 6 11:30:36 2017 +0100

    Fixed the broken GLSL shader and implemented the Disney BRDF in the
    real-time view port.

commit 8c7e11423be640dc44b1807912058480710e51f4
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Feb 3 14:24:05 2017 +0100

    Fix to comply strict compiler flags and some code cleanup

commit 17724e9d2dbffb1aaa61401224ecbf2349c1dac3
Merge: 379ba34 520afa2
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Jan 24 09:59:58 2017 +0100

    Merge branch 'master' into cycles_disney_brdf

commit 379ba346b0acd1ea779365b940fcd01f5ba1165f
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Jan 24 09:28:56 2017 +0100

    Renamed the Disney BSDF to Principled BSDF.

commit f80dcb4f34f1dc41841ced5965787fc26ace22a2
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Dec 2 13:55:12 2016 +0100

    Removed reflection call when roughness is low because of artifacts.

commit 732db8a57f6d4e5d6f44bbad176c15fd55377f0a
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed Nov 16 09:22:25 2016 +0100

    Indication if to use fresnel is now handled via the type of the BSDF.

commit 0103659f5e705b314cde98b0e4a01c14c55acd5e
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Nov 11 13:04:11 2016 +0100

    Fixed an error in the clearcoat where it appeared too bright for default
    light sources (like directional lights)

commit 0aa68f533529c9fd197a3ab0427f9e41a15456b9
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Nov 7 12:04:38 2016 +0100

    Resolved inconsistencies in using tabs and spaces

commit f5897a9494e352de274b99e7bee971336c0dc386
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Nov 7 08:13:41 2016 +0100

    Improved the clearcoat part by using GTR1 instead of GTR2

commit 3dfc240e61b3d4d0e7c476989792e4ada869ce91
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Oct 31 11:31:36 2016 +0100

    Use reflection BSDF for glossy reflections when roughness is 0.0 to
    reduce computational expense and some code cleanup

    Code cleanup includes:
    - Code style cleanup and removed unused code
    - Consolidated code in the bsdf_microfacet_multi_impl.h to reduce
      some computational expense

commit a2dd0c5fafdabe1573299170fb3be98a3e46d17a
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed Oct 26 08:51:10 2016 +0200

    Fixed glossy reflections and refractions for low roughness values and
    cleaned up the code.

    For low roughness values, the reflections had some strange behavior.

commit 981737591231a1a5a1c85950950580b65d029505
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Oct 25 12:37:40 2016 +0200

    Removed default values in setup functions and added extra functions for
    GGX with fresnel.

commit bbc5d9d4527346a74155cf17be21fb02ee3e0779
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Oct 25 11:09:36 2016 +0200

    Switched from uniform to cosine hemisphere sampling for the diffuse and
    the sheen part.

commit d52d8f2813d64363713f11160a6c725d4cafbcfa
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Oct 24 16:17:13 2016 +0200

    Removed the color parameters from the diffuse and sheen shader and use
    them as closure weights instead.

commit 8f3d92738532ad867a0a3543c00393626ab8f6ec
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Oct 24 09:57:06 2016 +0200

    Fixed the issue with artifacts when using anisotropy without linking the
    tangent input to a tangent node.

commit d93f680db9acaaade0354b34857a3ccaf348557f
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Oct 24 09:14:51 2016 +0200

    Added subsurface radius parameter to control the per color channel
    effection radius of the subsurface scattering.

commit c708c3e53b323773fc852bdc239bc51e157dcaef
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Oct 24 08:14:10 2016 +0200

    Rearranged the inputs of the shader.

commit dfbfff9c389074d3e5c1f49dd38a95e9b317eb1f
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Oct 21 09:27:05 2016 +0200

    Put spaces in the parameter names of the shader node

commit e5a748ced17c8f59e5e73309096adeea3ba95e04
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Oct 21 08:51:20 2016 +0200

    Removed code that isn't in use anymore

commit 75992bebc128c8b44cab4f0d8855603787f57260
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Oct 21 08:50:07 2016 +0200

    Code style cleanup

commit 4dfcf455f7769752044e051b399fb6a5dfcd0e22
Merge: 243a0e3 2cd6a89
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Thu Oct 20 10:41:50 2016 +0200

    Merge branch 'master' into cycles_disney_brdf

commit 243a0e3eb80ef82704d5ea2657384c3a4b9fb497
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Thu Oct 20 10:01:45 2016 +0200

    Switching between OSL and SVM is more consistant now when using Disney
    BSDF.

    There were some minor differences in the OSL implementation, e.g. the
    refraction roughness was missing.

commit 2a5ac509223c838285a00c4c12775567666e7154
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Sep 27 09:17:57 2016 +0200

    Fixed a bug that caused transparency to be always white when using OSL and
    selecting GGX as distribution of the Disney BSDF

commit e1fa8623915407cea942a07fd0a106b04e113c09
Merge: d0530a8 7f76f6f
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Sep 27 08:59:32 2016 +0200

    Merge branch 'master' into cycles_disney_brdf

commit d0530a8af0e076c0aca4c9a61b0a64cada45ac4d
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Sep 27 08:53:18 2016 +0200

    Cleanup the Disney BSDF implementation and removing unneeded files.

commit 3f4fc826bd9c1f47c694c0f6b2947daf5b524b1a
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Sep 27 08:36:07 2016 +0200

    Unified the OSL implementation of the Disney clearcoat as a simple
    microfacet shader like it was previously done in SVM

commit 4d3a0032ecea99031979f342bfd5f66ea5a8625a
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Sep 26 12:35:36 2016 +0200

    Enhanced performance for Disney materials without subsurface scattering

commit 3cd5eb56cf5c9006837f111c8866e4c6e1c2a6fd
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Sep 16 08:47:56 2016 +0200

    Fixed a bug in the Disney BSDF that caused specular reflections to be too
    bright and diffuse is now reacting to the roughness again

    - A normalization for the fresnel was missing which caused the specular
      reflections to become too bright for the single-scatter GGX
    - The roughness value for the diffuse BSSRDF part has always been
      overwritten and thus always 0
    - Also the performance for refractive materials with roughness=0.0 has
      been improved

commit 7cb37d711938e5626651db21f20da50edd96abaf
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Thu Sep 8 12:24:43 2016 +0200

    Added selection field to the Disney BSDF node for switching between
    "Multiscatter GGX" and "GGX"

    In the "GGX" mode there is an additional parameter for changing the
    refraction roughness for materials with smooth surfaces and rough interns
    (e.g. honey). With the "Multiscatter GGX" this effect can't be produced at
    the moment and so here will be no separation of the two roughness values.

commit cdd29d06bb86672ed0779eefb8eee95796b8f939
Merge: 02c315a b40d1c1
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Sep 6 15:59:05 2016 +0200

    Merge branch 'master' into cycles_disney_brdf

commit 02c315aeb0f0d7bb429d4396912e03dbb8a77340
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Sep 6 15:16:09 2016 +0200

    Implemented the OSL part of the Disney shader

commit 5f880293aeeacf269032824248b46d613691a36c
Merge: 630b80e b399a6d
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Sep 2 10:53:36 2016 +0200

    Merge branch 'master' into cycles_disney_brdf

commit 630b80e08b6acf83834bc95264af4ccdbbc5f82c
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Sep 2 10:52:13 2016 +0200

    Fresnel in the microfacet multiscatter implementation improved

commit 0d9f4d7acb2de65d1c98d425cea4bf364795c155
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Aug 26 11:11:05 2016 +0200

    Fixed refraction roughness problem (refractions were always 100% rough)
    and set IOR of clearcoat to 1.5

commit 9eed34c7d980e1b998df457c4f76021162c80f78
Merge: ef29aae ae475e3
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Aug 16 15:22:32 2016 +0200

    Merge branch 'master' into cycles_disney_brdf

commit ef29aaee1af8074e0228c480d962700e97ea5b36
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Aug 16 15:17:12 2016 +0200

    Implemented the fresnel in the multi-scatter GGX for the Disney BSDF

    - The specular/metallic part uses the multi-scatter GGX
    - The fresnel of the metallic part is controlled by the specular value
    - The color of the reflection part when using transparency can be
      controlled by the specularTint value

commit 88567af085ac94119b98c95246b6d6f63161bc01
Merge: cc267e5 285e082
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed Aug 3 15:05:09 2016 +0200

    Merge branch 'master' into cycles_disney_brdf

commit cc267e52f20d036a66aeeff127ee1c856f7c651b
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed Aug 3 15:00:25 2016 +0200

    Implemented the Disney clearcoat as a variation of the microfacet bsdf,
    removed the transparency roughness again and added an input for
    anisotropic rotations

commit 81f6c06b1f53180bf32a5c11ac1fa64e2b6abf52
Merge: ece5a08 7065022
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed Aug 3 11:42:02 2016 +0200

    Merge branch 'master' into cycles_disney_brdf

commit ece5a08e0d6e51a83c223ea87346134216e5b34e
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Jul 26 16:29:21 2016 +0200

    Base color now applied again to the refraction of transparent Disney
    materials

commit e3aff6849e06853c56da7bd610210dcab70e6070
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Jul 26 16:05:19 2016 +0200

    Added subsurface color parameter to the Disney shader

commit b3ca6d8a2f4f866b323fc2df0a3beff577218c27
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Jul 26 12:30:25 2016 +0200

    Improvement of the SSS in the Disney shader

     * Now the bump normal is correctly used for the SSS.
     * SSS in Disney uses the Disney diffuse shader

commit d68729300ee557e90a8e7e4be6eb8ef98db80fe2
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Jul 26 12:23:13 2016 +0200

    Better calculation of the Disney diffuse part

    Now the values for NdotL und NdotV are clamped to 0.0f for a better look
    when using normal maps

commit cb6e500b12e7bce884d3db19ee138c975c215f2d
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Jul 25 16:26:42 2016 +0200

    Now one can disable specular reflactions again by setting specular and
    metallic to 0 (cracked this in the previous commit)

commit bfb9cb11b548103369de2a46ce18b4ddf661362c
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Jul 25 16:11:07 2016 +0200

    fixed the Disney SSS and cleaned the initialization of the Disney shaders

commit 642c0fdad12548c1a2ccbf595bae3a995d3022f7
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Jul 25 16:09:55 2016 +0200

    fixed an error that was caused by the missing LABEL_REFLECT in the Disney
    diffuse shader

commit c10b484dcad3412c34455736e9656cd38716bcb0
Author: Jens Verwiebe <info@jensverwiebe.de>
Date:   Fri Jul 22 01:15:21 2016 +0200

    Rollback attempt to fix sss crashing, it prevented crash by disabling sss completely, thus useless

commit 462bba3f97fcc41834e0e20cc806a7958e5106f5
Author: Jens Verwiebe <info@jensverwiebe.de>
Date:   Thu Jul 21 23:11:59 2016 +0200

    Add an undef for sc_next for safety

commit 32d348577d69be251aa04110c5f6156cd2645f48
Author: Jens Verwiebe <info@jensverwiebe.de>
Date:   Thu Jul 21 00:15:48 2016 +0200

    Attempt to fix Disney SSS

commit dbad91ca6d46f5a4a6f2ba7ed4c811ffa723942f
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed Jul 20 11:13:00 2016 +0200

    Added a roughness parameter for refractions (for scattering of the rays
    within an object)

    With this, one can create a translucent material with a smooth surface and
    with a milky look.

    The final refraction roughness has to be calculated using the surface
    roughness and the refraction roughness because those two are correlated
    for refractions. If a ray hits a rough surface of a translucent material,
    it is scattered while entering the surface. Then it is scattered further
    within the object. The calculation I'm using is the following:

    RefrRoughnessFinal = 1.0 - (1.0 - Roughness) * (1.0 - RefrRoughness)

commit 50ea5e3e34394a727e3cceb6203adb48834a9ab7
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue Jun 7 10:24:50 2016 +0200

    Disney BSDF is now supporting CUDA

commit 10974cc826a4bfa8fb3ef59177abf0b0dc441065
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 31 11:18:07 2016 +0200

    Added parameters IOR and Transparency for refractions

    With this, the Disney BRDF/BSSRDF is extended by the BTDF part.

commit 218202c0905a4ec93ee19850360d1a39966d2c25
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon May 30 15:08:18 2016 +0200

    Added an additional normal for the clearcoat

    With this normal one can simulate a thin layer of clearcoat by applying a
    smoother normal map than the original to this input

commit dd139ead7e04aa87a894ccf3732cfce711258ff1
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon May 30 12:40:56 2016 +0200

    Switched to the improved subsurface scattering from Christensen and
    Burley

commit 11160fa4e1c32230119d4506e7e9fd3da2ab37f2
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon May 30 10:16:30 2016 +0200

    Added Disney Sheen shader as a preparation to get to a BSSRDF

commit cee4fe0cc94515ee60d4afa4d4e10c41003f1579
Merge: 4f955d0 6b5bab6
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon May 30 09:08:09 2016 +0200

    Merge branch 'cycles_disney_brdf' of git.blender.org:blender into cycles_disney_brdf

    Conflicts:
    	intern/cycles/kernel/closure/bsdf_disney_clearcoat.h
    	intern/cycles/kernel/closure/bsdf_disney_diffuse.h
    	intern/cycles/kernel/closure/bsdf_disney_specular.h
    	intern/cycles/kernel/closure/bsdf_util.h
    	intern/cycles/kernel/osl/CMakeLists.txt
    	intern/cycles/kernel/osl/bsdf_disney_clearcoat.cpp
    	intern/cycles/kernel/osl/bsdf_disney_diffuse.cpp
    	intern/cycles/kernel/osl/bsdf_disney_specular.cpp
    	intern/cycles/kernel/osl/osl_closures.h
    	intern/cycles/kernel/shaders/node_disney_bsdf.osl
    	intern/cycles/render/nodes.cpp
    	intern/cycles/render/nodes.h

commit 4f955d052358206209454decf2c3539e6a21b42f
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 24 16:38:23 2016 +0200

    SVM and OSL are both working for the simple version of the Disney BRDF

commit 1f5c41874b01ad297eb8a6bad9985296c6c0a6e1
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 24 09:58:50 2016 +0200

    Disney node can be used without SVM and started to cleanup the OSL implementation

    There is still some wrong behavior for SVM for the Schlick Fresnel part at the
    specular and clearcoat

commit d4b814e9304ebb44cc7c291cd83f7b7cdebcd152
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed May 18 10:22:29 2016 +0200

    Switched from a parameter struct for Disney parameters to ShaderClosure params

commit b86a1f5ba5019c7818153cb70b49f5f7a0bc52a0
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed May 18 10:19:57 2016 +0200

    Added additional variables for storing parameters in the ShaderClosure struct

commit 585b88623695fa07dfca9c9909d6d9184c3519c8
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 17 12:03:17 2016 +0200

    added output parameter to the DisneyBsdfNode

    That has been forgotten after removing the inheritance of BsdfNode

commit f91a28639884cbda7804715b910d64abba0718ef
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 17 10:40:48 2016 +0200

    removed BsdfNode class inheritance for DisneyBsdfNode

    That's due to a naming difference. The Disney BSDF uses the name 'Base Color'
    while the BsdfNode had a 'Color' input. That caused a text message to be
    printed while rendering.

commit 30da91c9c51d8cbc6a7564c7aaa61c9efe2ab654
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed May 4 16:08:10 2016 +0200

    disney implementation cleaned

commit 30d41da0f0352fad29375a395ffcb9cb7891eeb1
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed May 4 13:23:07 2016 +0200

    added the disney brdf as a shader node

commit 1f099fce249cb35e949cc629f7cca2167fca881a
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 3 16:54:49 2016 +0200

    added clearcoat implementation

commit 00a1378b98e435e9cdbfbac86eb974c19b2a8151
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Apr 29 22:56:49 2016 +0200

    disney diffuse und specular implemented

commit 6baa7a7eb787638661cddad0c4e7f78bd3a8fa5c
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Apr 18 15:21:32 2016 +0200

    disney diffuse is working correctly

commit d8fa169bf3caf71c40a124101b33dee6c510188e
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Apr 18 08:41:53 2016 +0200

    added vessel for disney diffuse shader

commit 6b5bab6cecde153122625cf8dc10e4209ed1eb0f
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed May 18 10:22:29 2016 +0200

    Switched from a parameter struct for Disney parameters to ShaderClosure params

commit f6499c2676e074a36033627ffc7540107777630d
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed May 18 10:19:57 2016 +0200

    Added additional variables for storing parameters in the ShaderClosure struct

commit 7100640b65c2ff5447a18c01fc4e93594b4f486a
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 17 12:03:17 2016 +0200

    added output parameter to the DisneyBsdfNode

    That has been forgotten after removing the inheritance of BsdfNode

commit 419ee5441100a906b4b3fd8373cb768a71bfdfe6
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 17 10:40:48 2016 +0200

    removed BsdfNode class inheritance for DisneyBsdfNode

    That's due to a naming difference. The Disney BSDF uses the name 'Base Color'
    while the BsdfNode had a 'Color' input. That caused a text message to be
    printed while rendering.

commit 6006f91e8730f78df5874f808690d3908db103ab
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed May 4 16:08:10 2016 +0200

    disney implementation cleaned

commit 0ed08959141fc7c5f8c6e37c6552ecb9fcc5749c
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Wed May 4 13:23:07 2016 +0200

    added the disney brdf as a shader node

commit 0630b742d71c658915575a4a71a325094a0fc313
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Tue May 3 16:54:49 2016 +0200

    added clearcoat implementation

commit 9f3d39744b85619750c79c901f678b8c07fe0ee2
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Fri Apr 29 22:56:49 2016 +0200

    disney diffuse und specular implemented

commit 9b262063767d6b05a617891c967d887d21bfb177
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Apr 18 15:21:32 2016 +0200

    disney diffuse is working correctly

commit 4711a3927dfcadaa1c36de0ba78fc304fac1dc8a
Author: Pascal Schoen <pascal_schoen@gmx.net>
Date:   Mon Apr 18 08:41:53 2016 +0200

    added vessel for disney diffuse shader

Differential Revision: https://developer.blender.org/D2313
2017-04-18 11:43:09 +02:00
Brecht Van Lommel
a3abb020e3 Fix Cycles CUDA performance on CUDA 8.0.
Mostly this is making inlining match CUDA 7.5 in a few performance critical
places. The end result is that performance is now better than before, possibly
due to less register spilling or other CUDA 8.0 compiler improvements.

On benchmarks scenes, there are 3% to 35% render time reductions. Stack memory
usage is reduced a little too.

Reviewed By: sergey

Differential Revision: https://developer.blender.org/D2269
2016-10-03 22:15:25 +02:00
Sergey Sharybin
6353ecb996 Cycles: Tweaks to support CUDA 8 toolkit
All the changes are mainly giving explicit tips on inlining functions,
so they match how inlining worked with previous toolkit.

This make kernel compiled by CUDA 8 render in average with same speed
as previous kernels. Some scenes are somewhat faster, some of them are
somewhat slower. But slowdown is within 1% so far.

On a positive side it allows us to enable newer generation cards on
buildbots (so GTX 10x0 will be officially supported soon).
2016-08-01 15:54:29 +02:00
Brecht Van Lommel
9b6ed3a42b Cycles: refactor kernel closure storage to use structs per closure type.
Reviewed By: dingto, sergey

Differential Revision: https://developer.blender.org/D2127
2016-07-31 02:34:43 +02:00
Sergey Sharybin
84c68dcb3f Cycles: Minor cleanup, whitespace around keyword and preprocessor indent 2016-04-13 08:58:52 +02:00
Sergey Sharybin
69dc0c3192 Cycles: Fixes for Burley BSSRDF
There are several fixes in here, which hopefully will make the shader
working correct without too much magic in there.

First of all, this commit brings BURLEY_TRUNCATE down from 30 to 16
which reduces noise a lot. It's still higher than original truncate
from Brecht, but this reduces PDF value at a cutoff distance by an
order of magnitude (now it's 0.008387, previously it was 0.063521
for the albedo of 0.8 and radius 1.0). This should converge to a
proper result faster and don't have artifacts.

This kind of reverts fix for T47356, but after additional thinking
came to conclusion Burley is not being totally smooth, it is about
giving less waxy results which it's kind of doing in the file.

Second of all, this commit fixes burley_eval() to use normalized
diffusion reflectance. This matches the way we calculate CDF and
solves numeric instability close to 0, making PDF profile looking
closer to other SSS profiles:

  https://developer.blender.org/F282355
  https://developer.blender.org/F282356
  https://developer.blender.org/F282357

Reviewers: brecht

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D1792
2016-02-13 13:29:13 +01:00
Sergey Sharybin
2ac88328b0 Cycles: Fix Burley's CDF truncation after recent radius fix
This is all not really ideal, but good enough for tonight.
More thoughts and investigation tomorrow!
2016-02-08 21:50:38 +01:00
Sergey Sharybin
dae8326d1e Fix T47356: Too sharp falloww with Burley BSSRDF
After the clamping commit we need to bump BURLEY_TRUNCATE
constant a bit, otherwise mean free path does not really
match the disk radius needed for importance sampling.
2016-02-08 14:54:11 +01:00
Brecht Van Lommel
4443bb8922 Fix Burley BSSRDF NaNs and fireflies.
Explicitly truncate to Rm same way as the Gaussian BSSRDF, and use safe_sqrtf()
to be sure in case of float precision issues.
2016-02-06 11:52:43 +01:00
Sergey Sharybin
e688a62712 Cycles: Fix for initial guess of the radius for Burley BSSRDF
The value was too high, causing bad Newton iteration step.
Now the value is not so good, but it's still within 9 iterations
and those high number of iterations are only happening in
approx 1% of input values.
2016-02-05 10:06:08 +01:00
Sergey Sharybin
3e7389eaf2 Cycles: Speedup of Christensen-Burley SSS falloff function
The idea is simply to pre-compute fitting and parameterization
in the bssrdf_setup() function and re-use the values in both
sample() and eval().

The only trick is where to store the pre-calculated values and
the answer is inside of ShaderClosure->custom{1,2,3}. There's
no memory bump here because we now simply re-use padding fields
for the pre-calculated values. Similar trick we can do for other
BSDFs.

Seems to give nice speedup up to 7% here on my desktop with
Core i7 CPU, SSE4.1 kernel.
2016-02-04 15:29:58 +01:00
Sergey Sharybin
ad26407b52 Cycles: Implement approximate reflectance profiles
Using this paper:

  http://graphics.pixar.com/library/ApproxBSSRDF/paper.pdf

This model gives less blurry results than the Cubic and Gaussian
we had implemented:

- Cubic: https://developer.blender.org/F279670
- Burley: https://developer.blender.org/F279671

The model is called "Christensen-Burley" in the interface, which
actually should be read as "Physically based" or "Realistic".

Reviewers: juicyfruit, dingto, lukasstockner97, brecht

Reviewed By: brecht, dingto

Subscribers: robocyte

Differential Revision: https://developer.blender.org/D1759
2016-02-04 13:27:23 +05:00
Sergey Sharybin
e42852a339 Cycles: Cleanup and reference actual paper used for BSSRDF sampling 2016-02-02 18:06:29 +01:00
Sergey Sharybin
ae7d84dbc1 Cycles: Use native saturate function for CUDA
This more a workaround for CUDA optimizer which can't optimize clamp(x, 0, 1)
into a single instruction and uses 4 instructions instead.

Original patch by @lockal with own modification:

  Don't make changes outside of the kernel. They don't make any difference
  anyway and term saturate() has a bit different meaning outside of kernel.

This gives around 2% of speedup in Barcelona file, but in more complex shader
setups with lots of math nodes with clamping speedup could be much nicer.

Subscribers: dingto

Projects: #cycles

Differential Revision: https://developer.blender.org/D1224
2015-04-28 00:38:32 +05:00
Sergey Sharybin
5ff132182d Cycles: Code cleanup, spaces around keywords
This inconsistency drove me totally crazy, it's really confusing
when it's inconsistent especially when you work on both Cycles and
Blender sides.

Shouldn;t cause merge PITA, it's whitespace changes only, Git should
be able to merge it nicely.
2015-03-28 00:15:15 +05:00
Sergey Sharybin
87cff57207 Fix T44123: Cycles SSS renders black in recent builds
Issue was introduced in 01ee21f where i didn't notice *_setup()
function only doing partial initialization, and some of parameters
are expected to be initialized by callee function.

This was hitting only some setups, so tests with benchmark scenes
didn't unleash issues. Now it should all be fine.

This is to go to the 2.74 branch and we actually might re-AHOY.
2015-03-25 02:33:49 +05:00
Sergey Sharybin
ed7e593a4b Fix T43926: Volume scatter: intersecting objects GPU rendering artifacts
Fix T44007: Cycles Volumetrics: block artifacts with overlapping volumes

The issue was caused by uninitialized parameters of some closures, which
lead to unpredictable behavior of shader_merge_closures().
2015-03-23 12:48:33 +05:00
Thomas Dinges
ee36e75b85 Cleanup: Fix Cycles Apache header.
This was already mixed a bit, but the dot belongs there.
2014-12-25 02:50:24 +01:00
Brecht Van Lommel
c18712e868 Cycles: change __device and similar qualifiers to ccl_device in kernel code.
This to avoids build conflicts with libc++ on FreeBSD, these __ prefixed values
are reserved for compilers. I apologize to anyone who has patches or branches
and has to go through the pain of merging this change, it may be easiest to do
these same replacements in your code and then apply/merge the patch.

Ref T37477.
2013-11-18 08:48:15 +01:00
Brecht Van Lommel
b314209356 Cycles: add a sharpness input to the Cubic SSS falloff. When set to 1 this will
give a result more similar to the Compatible falloff option. The scale is x2
though to keep the perceived scatter radius roughly the same while changing the
sharpness. Difference with compatible will be mainly on non-flat geometry.
2013-09-03 22:39:17 +00:00
Brecht Van Lommel
841fe45df9 Cycles: change Gaussian subsurface scattering falloff to be more similar to
the Cubic falloff, see here for details.
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/Shaders#Subsurface_Scattering
2013-08-28 19:22:46 +00:00
Brecht Van Lommel
b9ce231060 Cycles: relicense GNU GPL source code to Apache version 2.0.
More information in this post:
http://code.blender.org/

Thanks to all contributes for giving their permission!
2013-08-18 14:16:15 +00:00
Brecht Van Lommel
d43682d51b Cycles: Subsurface Scattering
New features:

* Bump mapping now works with SSS
* Texture Blur factor for SSS, see the documentation for details:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/Shaders#Subsurface_Scattering

Work in progress for feedback:

Initial implementation of the "BSSRDF Importance Sampling" paper, which uses
a different importance sampling method. It gives better quality results in
many ways, with the availability of both Cubic and Gaussian falloff functions,
but also tends to be more noisy when using the progressive integrator and does
not give great results with some geometry. It works quite well for the
non-progressive integrator and is often less noisy there.

This code may still change a lot, so unless you're testing it may be best to
stick to the Compatible falloff function.

Skin test render and file that takes advantage of the gaussian falloff:
http://www.pasteall.org/pic/show.php?id=57661
http://www.pasteall.org/pic/show.php?id=57662
http://www.pasteall.org/blend/23501
2013-08-18 14:15:57 +00:00