diff options
Diffstat (limited to 'intern/cycles/kernel/kernel_shader.h')
| -rw-r--r-- | intern/cycles/kernel/kernel_shader.h | 50 |
1 files changed, 33 insertions, 17 deletions
diff --git a/intern/cycles/kernel/kernel_shader.h b/intern/cycles/kernel/kernel_shader.h index 88aa1f712a4..5ef4475e259 100644 --- a/intern/cycles/kernel/kernel_shader.h +++ b/intern/cycles/kernel/kernel_shader.h @@ -575,7 +575,8 @@ void shader_bsdf_eval(KernelGlobals *kg, } } -ccl_device_inline const ShaderClosure *shader_bsdf_pick(ShaderData *sd) +ccl_device_inline const ShaderClosure *shader_bsdf_pick(ShaderData *sd, + float *randu) { int sampled = 0; @@ -591,19 +592,25 @@ ccl_device_inline const ShaderClosure *shader_bsdf_pick(ShaderData *sd) } } - float r = sd->randb_closure*sum; + float r = (*randu)*sum; float partial_sum = 0.0f; for(int i = 0; i < sd->num_closure; i++) { const ShaderClosure *sc = &sd->closure[i]; if(CLOSURE_IS_BSDF(sc->type)) { - partial_sum += sc->sample_weight; + float next_sum = partial_sum + sc->sample_weight; - if(r <= partial_sum) { + if(r < next_sum) { sampled = i; + + /* Rescale to reuse for direction sample, to better + * preserve stratifaction. */ + *randu = (r - partial_sum) / sc->sample_weight; break; } + + partial_sum = next_sum; } } } @@ -612,7 +619,8 @@ ccl_device_inline const ShaderClosure *shader_bsdf_pick(ShaderData *sd) } ccl_device_inline const ShaderClosure *shader_bssrdf_pick(ShaderData *sd, - ccl_addr_space float3 *throughput) + ccl_addr_space float3 *throughput, + float *randu) { int sampled = 0; @@ -632,16 +640,16 @@ ccl_device_inline const ShaderClosure *shader_bssrdf_pick(ShaderData *sd, } } - float r = sd->randb_closure*(sum_bsdf + sum_bssrdf); + float r = (*randu)*(sum_bsdf + sum_bssrdf); float partial_sum = 0.0f; for(int i = 0; i < sd->num_closure; i++) { const ShaderClosure *sc = &sd->closure[i]; if(CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { - partial_sum += sc->sample_weight; + float next_sum = partial_sum + sc->sample_weight; - if(r <= partial_sum) { + if(r < next_sum) { if(CLOSURE_IS_BSDF(sc->type)) { *throughput *= (sum_bsdf + sum_bssrdf) / sum_bsdf; return NULL; @@ -649,9 +657,15 @@ ccl_device_inline const ShaderClosure *shader_bssrdf_pick(ShaderData *sd, else { *throughput *= (sum_bsdf + sum_bssrdf) / sum_bssrdf; sampled = i; + + /* Rescale to reuse for direction sample, to better + * preserve stratifaction. */ + *randu = (r - partial_sum) / sc->sample_weight; break; } } + + partial_sum = next_sum; } } } @@ -667,7 +681,7 @@ ccl_device_inline int shader_bsdf_sample(KernelGlobals *kg, differential3 *domega_in, float *pdf) { - const ShaderClosure *sc = shader_bsdf_pick(sd); + const ShaderClosure *sc = shader_bsdf_pick(sd, &randu); if(!sc) { *pdf = 0.0f; return LABEL_NONE; @@ -923,11 +937,10 @@ ccl_device float3 shader_holdout_eval(KernelGlobals *kg, ShaderData *sd) /* Surface Evaluation */ ccl_device void shader_eval_surface(KernelGlobals *kg, ShaderData *sd, - ccl_addr_space PathState *state, float randb, int path_flag) + ccl_addr_space PathState *state, int path_flag) { sd->num_closure = 0; sd->num_closure_extra = 0; - sd->randb_closure = randb; #ifdef __OSL__ if(kg->osl) @@ -958,7 +971,6 @@ ccl_device float3 shader_eval_background(KernelGlobals *kg, ShaderData *sd, { sd->num_closure = 0; sd->num_closure_extra = 0; - sd->randb_closure = 0.0f; #ifdef __SVM__ #ifdef __OSL__ @@ -1040,17 +1052,22 @@ ccl_device int shader_volume_phase_sample(KernelGlobals *kg, const ShaderData *s sum += sc->sample_weight; } - float r = sd->randb_closure*sum; - sum = 0.0f; + float r = randu*sum; + float partial_sum = 0.0f; for(sampled = 0; sampled < sd->num_closure; sampled++) { const ShaderClosure *sc = &sd->closure[sampled]; if(CLOSURE_IS_PHASE(sc->type)) { - sum += sc->sample_weight; + float next_sum = partial_sum + sc->sample_weight; - if(r <= sum) + if(r <= next_sum) { + /* Rescale to reuse for BSDF direction sample. */ + randu = (r - partial_sum) / sc->sample_weight; break; + } + + partial_sum = next_sum; } } @@ -1154,7 +1171,6 @@ ccl_device void shader_eval_displacement(KernelGlobals *kg, ShaderData *sd, ccl_ { sd->num_closure = 0; sd->num_closure_extra = 0; - sd->randb_closure = 0.0f; /* this will modify sd->P */ #ifdef __SVM__ |