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

1 files changed, 3 insertions, 11 deletions

diff --git a/source/blender/gpu/shaders/material/gpu_shader_material_subsurface_scattering.glsl b/source/blender/gpu/shaders/material/gpu_shader_material_subsurface_scattering.glsl
index 5129bf71903..d0c159cdf37 100644
--- a/source/blender/gpu/shaders/material/gpu_shader_material_subsurface_scattering.glsl
+++ b/source/blender/gpu/shaders/material/gpu_shader_material_subsurface_scattering.glsl
@@ -5,8 +5,8 @@ CLOSURE_EVAL_FUNCTION_DECLARE_1(node_subsurface_scattering, Diffuse)
 void node_subsurface_scattering(vec4 color,
                                 float scale,
                                 vec3 radius,
-                                float sharpen,
-                                float texture_blur,
+                                float ior,
+                                float anisotropy,
                                 vec3 N,
                                 float sss_id,
                                 out Closure result)
@@ -20,15 +20,7 @@ void node_subsurface_scattering(vec4 color,
 
   result = CLOSURE_DEFAULT;
 
-  /* Not perfect for texture_blur values between 0.0 and 1.0.
-   * Interpolate between separated color and color applied on irradiance. */
-  float one_minus_texture_blur = 1.0 - texture_blur;
-  vec3 sss_albedo = color.rgb * one_minus_texture_blur + texture_blur;
-  vec3 radiance_tint = color.rgb * texture_blur + one_minus_texture_blur;
-  /* Consider output radiance as irradiance. */
-  out_Diffuse_0.radiance *= radiance_tint;
-
-  closure_load_sss_data(scale, out_Diffuse_0.radiance, sss_albedo, int(sss_id), result);
+  closure_load_sss_data(scale, out_Diffuse_0.radiance, color.rgb, int(sss_id), result);
 
   /* TODO(fclem) Try to not use this. */
   closure_load_ssr_data(vec3(0.0), 0.0, in_Diffuse_0.N, -1.0, result);