diff options
Diffstat (limited to 'intern/cycles/kernel/kernel_random.h')
| -rw-r--r-- | intern/cycles/kernel/kernel_random.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/intern/cycles/kernel/kernel_random.h b/intern/cycles/kernel/kernel_random.h index df876e6f726..ba97ab3e3b6 100644 --- a/intern/cycles/kernel/kernel_random.h +++ b/intern/cycles/kernel/kernel_random.h @@ -22,6 +22,11 @@ typedef uint RNG; #ifdef __SOBOL__ +/* skip initial numbers that are not as well distributed, especially the + first sequence is just 0 everywhere, which can be problematic for e.g. + path termination */ +#define SOBOL_SKIP 64 + /* High Dimensional Sobol */ /* van der corput radical inverse */ @@ -103,7 +108,7 @@ __device_inline float path_rng(KernelGlobals *kg, RNG *rng, int sample, int dime return r; #else /* compute sobol sequence value using direction vectors */ - uint result = sobol_dimension(kg, sample, dimension); + uint result = sobol_dimension(kg, sample + SOBOL_SKIP, dimension); float r = (float)result * (1.0f/(float)0xFFFFFFFF); /* Cranly-Patterson rotation using rng seed */ |