Eevee: SSS: Add Christensen-Burley diffusion profile.

This seems to be a correct implementation of the same diffusion profile as Cycles uses by default.

There are a few bias though:
- We consider _A_ the albedo to be 1 when evaluating _s_.
- We use a factor of 0.6 when computing _d_ to match more or less cycles results.

Note that doing per pixel jittering does bias the result even further (loss of energy).

1 files changed, 1 insertions, 1 deletions

diff --git a/source/blender/gpu/GPU_material.h b/source/blender/gpu/GPU_material.h
index 4b9f3c1d519..2a72b6996c4 100644
--- a/source/blender/gpu/GPU_material.h
+++ b/source/blender/gpu/GPU_material.h
@@ -235,7 +235,7 @@ void GPU_material_enable_alpha(GPUMaterial *material);
 GPUBuiltin GPU_get_material_builtins(GPUMaterial *material);
 GPUBlendMode GPU_material_alpha_blend(GPUMaterial *material, float obcol[4]);
 
-void GPU_material_sss_profile_create(GPUMaterial *material, float *radii);
+void GPU_material_sss_profile_create(GPUMaterial *material, float *radii, int *falloff_type);
 struct GPUUniformBuffer *GPU_material_sss_profile_get(GPUMaterial *material, int sample_ct);
 
 /* High level functions to create and use GPU materials */