diff options
Diffstat (limited to 'intern/cycles/kernel/kernel_random.h')
| -rw-r--r-- | intern/cycles/kernel/kernel_random.h | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/intern/cycles/kernel/kernel_random.h b/intern/cycles/kernel/kernel_random.h index 2b767da5041..e773753396f 100644 --- a/intern/cycles/kernel/kernel_random.h +++ b/intern/cycles/kernel/kernel_random.h @@ -120,13 +120,11 @@ ccl_device_forceinline float path_rng_1D(KernelGlobals *kg, ccl_addr_space RNG * /* Cranly-Patterson rotation using rng seed */ float shift; - /* using the same *rng value to offset seems to give correlation issues, - * we could hash it with the dimension but this has a performance impact, - * we need to find a solution for this */ - if(dimension & 1) - shift = (*rng >> 16) * (1.0f/(float)0xFFFF); - else - shift = (*rng & 0xFFFF) * (1.0f/(float)0xFFFF); + /* Hash rng with dimension to solve correlation issues. + * See T38710, T50116. + */ + RNG tmp_rng = cmj_hash_simple(dimension, *rng); + shift = tmp_rng * (1.0f/(float)0xFFFFFFFF); return r + shift - floorf(r + shift); #endif |