diff options
| author | Brecht Van Lommel <brechtvanlommel@gmail.com> | 2018-01-21 16:04:22 +0300 |
|---|---|---|
| committer | Brecht Van Lommel <brechtvanlommel@gmail.com> | 2018-02-09 21:58:33 +0300 |
| commit | 0df9b2c71517a98760a5e577f434d9d86e4e1910 (patch) | |
| tree | eee5839a1e6408af8c0e1766f37e68a8aadfbfb2 /intern/cycles/kernel/svm | |
| parent | 3ab5ef7b4f34f110e4861096428b83b4f9b5efe9 (diff) | |
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
Diffstat (limited to 'intern/cycles/kernel/svm')
| -rw-r--r-- | intern/cycles/kernel/svm/svm_closure.h | 3 | ||||
| -rw-r--r-- | intern/cycles/kernel/svm/svm_types.h | 6 |
2 files changed, 6 insertions, 3 deletions
diff --git a/intern/cycles/kernel/svm/svm_closure.h b/intern/cycles/kernel/svm/svm_closure.h index 578434792e4..f013dc396d0 100644 --- a/intern/cycles/kernel/svm/svm_closure.h +++ b/intern/cycles/kernel/svm/svm_closure.h @@ -764,7 +764,8 @@ ccl_device void svm_node_closure_bsdf(KernelGlobals *kg, ShaderData *sd, float * #ifdef __SUBSURFACE__ case CLOSURE_BSSRDF_CUBIC_ID: case CLOSURE_BSSRDF_GAUSSIAN_ID: - case CLOSURE_BSSRDF_BURLEY_ID: { + case CLOSURE_BSSRDF_BURLEY_ID: + case CLOSURE_BSSRDF_RANDOM_WALK_ID: { float3 weight = sd->svm_closure_weight * mix_weight; Bssrdf *bssrdf = bssrdf_alloc(sd, weight); diff --git a/intern/cycles/kernel/svm/svm_types.h b/intern/cycles/kernel/svm/svm_types.h index 6ff04a65462..9a87b4ee358 100644 --- a/intern/cycles/kernel/svm/svm_types.h +++ b/intern/cycles/kernel/svm/svm_types.h @@ -446,6 +446,7 @@ typedef enum ClosureType { CLOSURE_BSSRDF_GAUSSIAN_ID, CLOSURE_BSSRDF_PRINCIPLED_ID, CLOSURE_BSSRDF_BURLEY_ID, + CLOSURE_BSSRDF_RANDOM_WALK_ID, /* Other */ CLOSURE_HOLDOUT_ID, @@ -477,8 +478,9 @@ typedef enum ClosureType { #define CLOSURE_IS_BSDF_MICROFACET(type) ((type >= CLOSURE_BSDF_MICROFACET_GGX_ID && type <= CLOSURE_BSDF_ASHIKHMIN_SHIRLEY_ANISO_ID) ||\ (type >= CLOSURE_BSDF_MICROFACET_BECKMANN_REFRACTION_ID && type <= CLOSURE_BSDF_MICROFACET_MULTI_GGX_GLASS_ID) ||\ (type == CLOSURE_BSDF_MICROFACET_MULTI_GGX_GLASS_FRESNEL_ID)) -#define CLOSURE_IS_BSDF_OR_BSSRDF(type) (type <= CLOSURE_BSSRDF_BURLEY_ID) -#define CLOSURE_IS_BSSRDF(type) (type >= CLOSURE_BSSRDF_CUBIC_ID && type <= CLOSURE_BSSRDF_BURLEY_ID) +#define CLOSURE_IS_BSDF_OR_BSSRDF(type) (type <= CLOSURE_BSSRDF_RANDOM_WALK_ID) +#define CLOSURE_IS_BSSRDF(type) (type >= CLOSURE_BSSRDF_CUBIC_ID && type <= CLOSURE_BSSRDF_RANDOM_WALK_ID) +#define CLOSURE_IS_DISK_BSSRDF(type) (type >= CLOSURE_BSSRDF_CUBIC_ID && type <= CLOSURE_BSSRDF_BURLEY_ID) #define CLOSURE_IS_VOLUME(type) (type >= CLOSURE_VOLUME_ID && type <= CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID) #define CLOSURE_IS_VOLUME_SCATTER(type) (type == CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID) #define CLOSURE_IS_VOLUME_ABSORPTION(type) (type == CLOSURE_VOLUME_ABSORPTION_ID) |