Cycles: MIS for lamps now loops over all lamps instead of picking one.

Probably will not be noticed in most scenes. This helps reduce noise when you
have multiple lamps with MIS enabled, at the cost of some performance, but from
testing some scenes this seems better.
This commit is contained in:
Brecht Van Lommel 2014-05-01 19:18:42 +02:00
parent 95b93b5d46
commit c806a8ce96
3 changed files with 28 additions and 27 deletions

View File

@ -183,38 +183,42 @@ ccl_device_noinline float3 indirect_primitive_emission(KernelGlobals *kg, Shader
/* Indirect Lamp Emission */
ccl_device_noinline bool indirect_lamp_emission(KernelGlobals *kg, PathState *state, Ray *ray, float randt, float3 *emission)
ccl_device_noinline bool indirect_lamp_emission(KernelGlobals *kg, PathState *state, Ray *ray, float3 *emission)
{
LightSample ls;
int lamp = lamp_light_eval_sample(kg, randt);
bool hit_lamp = false;
if(lamp == LAMP_NONE)
return false;
*emission = make_float3(0.0f, 0.0f, 0.0f);
if(!lamp_light_eval(kg, lamp, ray->P, ray->D, ray->t, &ls))
return false;
for(int lamp = 0; lamp < kernel_data.integrator.num_all_lights; lamp++) {
LightSample ls;
if(!lamp_light_eval(kg, lamp, ray->P, ray->D, ray->t, &ls))
continue;
#ifdef __PASSES__
/* use visibility flag to skip lights */
if(ls.shader & SHADER_EXCLUDE_ANY) {
if(((ls.shader & SHADER_EXCLUDE_DIFFUSE) && (state->flag & PATH_RAY_DIFFUSE)) ||
((ls.shader & SHADER_EXCLUDE_GLOSSY) && (state->flag & PATH_RAY_GLOSSY)) ||
((ls.shader & SHADER_EXCLUDE_TRANSMIT) && (state->flag & PATH_RAY_TRANSMIT)))
return false;
}
/* use visibility flag to skip lights */
if(ls.shader & SHADER_EXCLUDE_ANY) {
if(((ls.shader & SHADER_EXCLUDE_DIFFUSE) && (state->flag & PATH_RAY_DIFFUSE)) ||
((ls.shader & SHADER_EXCLUDE_GLOSSY) && (state->flag & PATH_RAY_GLOSSY)) ||
((ls.shader & SHADER_EXCLUDE_TRANSMIT) && (state->flag & PATH_RAY_TRANSMIT)))
continue;
}
#endif
float3 L = direct_emissive_eval(kg, &ls, -ray->D, ray->dD, ls.t, ray->time, state->bounce, state->transparent_bounce);
float3 L = direct_emissive_eval(kg, &ls, -ray->D, ray->dD, ls.t, ray->time, state->bounce, state->transparent_bounce);
if(!(state->flag & PATH_RAY_MIS_SKIP)) {
/* multiple importance sampling, get regular light pdf,
* and compute weight with respect to BSDF pdf */
float mis_weight = power_heuristic(state->ray_pdf, ls.pdf);
L *= mis_weight;
if(!(state->flag & PATH_RAY_MIS_SKIP)) {
/* multiple importance sampling, get regular light pdf,
* and compute weight with respect to BSDF pdf */
float mis_weight = power_heuristic(state->ray_pdf, ls.pdf);
L *= mis_weight;
}
*emission += L;
hit_lamp = true;
}
*emission = L;
return true;
return hit_lamp;
}
/* Indirect Background */

View File

@ -421,7 +421,6 @@ ccl_device bool lamp_light_eval(KernelGlobals *kg, int lamp, float3 P, float3 D,
/* compute pdf */
if(ls->t != FLT_MAX)
ls->pdf *= lamp_light_pdf(kg, ls->Ng, -ls->D, ls->t);
ls->eval_fac *= kernel_data.integrator.inv_pdf_lights;
return true;
}

View File

@ -240,10 +240,9 @@ ccl_device void kernel_path_indirect(KernelGlobals *kg, RNG *rng, Ray ray, ccl_g
light_ray.dP = ray.dP;
/* intersect with lamp */
float light_t = path_state_rng_1D(kg, rng, &state, PRNG_LIGHT);
float3 emission;
if(indirect_lamp_emission(kg, &state, &light_ray, light_t, &emission))
if(indirect_lamp_emission(kg, &state, &light_ray, &emission))
path_radiance_accum_emission(L, throughput, emission, state.bounce);
}
#endif
@ -624,10 +623,9 @@ ccl_device float4 kernel_path_integrate(KernelGlobals *kg, RNG *rng, int sample,
light_ray.dP = ray.dP;
/* intersect with lamp */
float light_t = path_state_rng_1D(kg, rng, &state, PRNG_LIGHT);
float3 emission;
if(indirect_lamp_emission(kg, &state, &light_ray, light_t, &emission))
if(indirect_lamp_emission(kg, &state, &light_ray, &emission))
path_radiance_accum_emission(&L, throughput, emission, state.bounce);
}
#endif