forked from bartvdbraak/blender
83e73a2100
This commit changes the way how we pass bounce information to the Light Path node. Instead of manualy copying the bounces into ShaderData, we now directly pass PathState. This reduces the arguments that we need to pass around and also makes it easier to extend the feature. This commit also exposes the Transmission Bounce Depth to the Light Path node. It works similar to the Transparent Depth Output: Replace a Transmission lightpath after X bounces with another shader, e.g a Diffuse one. This can be used to avoid black surfaces, due to low amount of max bounces. Reviewed by Sergey and Brecht, thanks for some hlp with this. I tested compilation and usage on CPU (SVM and OSL), CUDA, OpenCL Split and Mega kernel. Hopefully this covers all devices. :)
271 lines
8.2 KiB
C
271 lines
8.2 KiB
C
/*
|
|
* Copyright 2011-2013 Blender Foundation
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
CCL_NAMESPACE_BEGIN
|
|
|
|
#ifdef __VOLUME_SCATTER__
|
|
|
|
ccl_device void kernel_path_volume_connect_light(KernelGlobals *kg, RNG *rng,
|
|
ShaderData *sd, float3 throughput, PathState *state, PathRadiance *L)
|
|
{
|
|
#ifdef __EMISSION__
|
|
if(!kernel_data.integrator.use_direct_light)
|
|
return;
|
|
|
|
/* sample illumination from lights to find path contribution */
|
|
float light_t = path_state_rng_1D(kg, rng, state, PRNG_LIGHT);
|
|
float light_u, light_v;
|
|
path_state_rng_2D(kg, rng, state, PRNG_LIGHT_U, &light_u, &light_v);
|
|
|
|
Ray light_ray;
|
|
BsdfEval L_light;
|
|
LightSample ls;
|
|
bool is_lamp;
|
|
|
|
/* connect to light from given point where shader has been evaluated */
|
|
#ifdef __OBJECT_MOTION__
|
|
light_ray.time = sd->time;
|
|
#endif
|
|
|
|
light_sample(kg, light_t, light_u, light_v, sd->time, sd->P, state->bounce, &ls);
|
|
if(ls.pdf == 0.0f)
|
|
return;
|
|
|
|
if(direct_emission(kg, sd, &ls, state, &light_ray, &L_light, &is_lamp)) {
|
|
/* trace shadow ray */
|
|
float3 shadow;
|
|
|
|
if(!shadow_blocked(kg, state, &light_ray, &shadow)) {
|
|
/* accumulate */
|
|
path_radiance_accum_light(L, throughput, &L_light, shadow, 1.0f, state->bounce, is_lamp);
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
#ifdef __KERNEL_GPU__
|
|
ccl_device_noinline
|
|
#else
|
|
ccl_device
|
|
#endif
|
|
bool kernel_path_volume_bounce(KernelGlobals *kg, RNG *rng,
|
|
ShaderData *sd, float3 *throughput, PathState *state, PathRadiance *L, Ray *ray)
|
|
{
|
|
/* sample phase function */
|
|
float phase_pdf;
|
|
BsdfEval phase_eval;
|
|
float3 phase_omega_in;
|
|
differential3 phase_domega_in;
|
|
float phase_u, phase_v;
|
|
path_state_rng_2D(kg, rng, state, PRNG_PHASE_U, &phase_u, &phase_v);
|
|
int label;
|
|
|
|
label = shader_volume_phase_sample(kg, sd, phase_u, phase_v, &phase_eval,
|
|
&phase_omega_in, &phase_domega_in, &phase_pdf);
|
|
|
|
if(phase_pdf == 0.0f || bsdf_eval_is_zero(&phase_eval))
|
|
return false;
|
|
|
|
/* modify throughput */
|
|
path_radiance_bsdf_bounce(L, throughput, &phase_eval, phase_pdf, state->bounce, label);
|
|
|
|
/* set labels */
|
|
state->ray_pdf = phase_pdf;
|
|
#ifdef __LAMP_MIS__
|
|
state->ray_t = 0.0f;
|
|
#endif
|
|
state->min_ray_pdf = fminf(phase_pdf, state->min_ray_pdf);
|
|
|
|
/* update path state */
|
|
path_state_next(kg, state, label);
|
|
|
|
/* setup ray */
|
|
ray->P = sd->P;
|
|
ray->D = phase_omega_in;
|
|
ray->t = FLT_MAX;
|
|
|
|
#ifdef __RAY_DIFFERENTIALS__
|
|
ray->dP = sd->dP;
|
|
ray->dD = phase_domega_in;
|
|
#endif
|
|
|
|
return true;
|
|
}
|
|
|
|
ccl_device void kernel_branched_path_volume_connect_light(KernelGlobals *kg, RNG *rng,
|
|
ShaderData *sd, float3 throughput, PathState *state, PathRadiance *L,
|
|
bool sample_all_lights, Ray *ray, const VolumeSegment *segment)
|
|
{
|
|
#ifdef __EMISSION__
|
|
if(!kernel_data.integrator.use_direct_light)
|
|
return;
|
|
|
|
Ray light_ray;
|
|
BsdfEval L_light;
|
|
bool is_lamp;
|
|
|
|
#ifdef __OBJECT_MOTION__
|
|
light_ray.time = sd->time;
|
|
#endif
|
|
|
|
if(sample_all_lights) {
|
|
/* lamp sampling */
|
|
for(int i = 0; i < kernel_data.integrator.num_all_lights; i++) {
|
|
if(UNLIKELY(light_select_reached_max_bounces(kg, i, state->bounce)))
|
|
continue;
|
|
|
|
int num_samples = light_select_num_samples(kg, i);
|
|
float num_samples_inv = 1.0f/(num_samples*kernel_data.integrator.num_all_lights);
|
|
RNG lamp_rng = cmj_hash(*rng, i);
|
|
|
|
if(kernel_data.integrator.pdf_triangles != 0.0f)
|
|
num_samples_inv *= 0.5f;
|
|
|
|
for(int j = 0; j < num_samples; j++) {
|
|
/* sample random position on given light */
|
|
float light_u, light_v;
|
|
path_branched_rng_2D(kg, &lamp_rng, state, j, num_samples, PRNG_LIGHT_U, &light_u, &light_v);
|
|
|
|
LightSample ls;
|
|
lamp_light_sample(kg, i, light_u, light_v, ray->P, &ls);
|
|
|
|
float3 tp = throughput;
|
|
|
|
/* sample position on volume segment */
|
|
float rphase = path_branched_rng_1D_for_decision(kg, rng, state, j, num_samples, PRNG_PHASE);
|
|
float rscatter = path_branched_rng_1D_for_decision(kg, rng, state, j, num_samples, PRNG_SCATTER_DISTANCE);
|
|
|
|
VolumeIntegrateResult result = kernel_volume_decoupled_scatter(kg,
|
|
state, ray, sd, &tp, rphase, rscatter, segment, (ls.t != FLT_MAX)? &ls.P: NULL, false);
|
|
|
|
(void)result;
|
|
kernel_assert(result == VOLUME_PATH_SCATTERED);
|
|
|
|
/* todo: split up light_sample so we don't have to call it again with new position */
|
|
lamp_light_sample(kg, i, light_u, light_v, sd->P, &ls);
|
|
|
|
if(ls.pdf == 0.0f)
|
|
continue;
|
|
|
|
if(direct_emission(kg, sd, &ls, state, &light_ray, &L_light, &is_lamp)) {
|
|
/* trace shadow ray */
|
|
float3 shadow;
|
|
|
|
if(!shadow_blocked(kg, state, &light_ray, &shadow)) {
|
|
/* accumulate */
|
|
path_radiance_accum_light(L, tp*num_samples_inv, &L_light, shadow, num_samples_inv, state->bounce, is_lamp);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* mesh light sampling */
|
|
if(kernel_data.integrator.pdf_triangles != 0.0f) {
|
|
int num_samples = kernel_data.integrator.mesh_light_samples;
|
|
float num_samples_inv = 1.0f/num_samples;
|
|
|
|
if(kernel_data.integrator.num_all_lights)
|
|
num_samples_inv *= 0.5f;
|
|
|
|
for(int j = 0; j < num_samples; j++) {
|
|
/* sample random position on random triangle */
|
|
float light_t = path_branched_rng_1D_for_decision(kg, rng, state, j, num_samples, PRNG_LIGHT);
|
|
float light_u, light_v;
|
|
path_branched_rng_2D(kg, rng, state, j, num_samples, PRNG_LIGHT_U, &light_u, &light_v);
|
|
|
|
/* only sample triangle lights */
|
|
if(kernel_data.integrator.num_all_lights)
|
|
light_t = 0.5f*light_t;
|
|
|
|
LightSample ls;
|
|
light_sample(kg, light_t, light_u, light_v, sd->time, ray->P, state->bounce, &ls);
|
|
|
|
float3 tp = throughput;
|
|
|
|
/* sample position on volume segment */
|
|
float rphase = path_branched_rng_1D_for_decision(kg, rng, state, j, num_samples, PRNG_PHASE);
|
|
float rscatter = path_branched_rng_1D_for_decision(kg, rng, state, j, num_samples, PRNG_SCATTER_DISTANCE);
|
|
|
|
VolumeIntegrateResult result = kernel_volume_decoupled_scatter(kg,
|
|
state, ray, sd, &tp, rphase, rscatter, segment, (ls.t != FLT_MAX)? &ls.P: NULL, false);
|
|
|
|
(void)result;
|
|
kernel_assert(result == VOLUME_PATH_SCATTERED);
|
|
|
|
/* todo: split up light_sample so we don't have to call it again with new position */
|
|
light_sample(kg, light_t, light_u, light_v, sd->time, sd->P, state->bounce, &ls);
|
|
|
|
if(ls.pdf == 0.0f)
|
|
continue;
|
|
|
|
if(direct_emission(kg, sd, &ls, state, &light_ray, &L_light, &is_lamp)) {
|
|
/* trace shadow ray */
|
|
float3 shadow;
|
|
|
|
if(!shadow_blocked(kg, state, &light_ray, &shadow)) {
|
|
/* accumulate */
|
|
path_radiance_accum_light(L, tp*num_samples_inv, &L_light, shadow, num_samples_inv, state->bounce, is_lamp);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
else {
|
|
/* sample random position on random light */
|
|
float light_t = path_state_rng_1D(kg, rng, state, PRNG_LIGHT);
|
|
float light_u, light_v;
|
|
path_state_rng_2D(kg, rng, state, PRNG_LIGHT_U, &light_u, &light_v);
|
|
|
|
LightSample ls;
|
|
light_sample(kg, light_t, light_u, light_v, sd->time, ray->P, state->bounce, &ls);
|
|
|
|
float3 tp = throughput;
|
|
|
|
/* sample position on volume segment */
|
|
float rphase = path_state_rng_1D_for_decision(kg, rng, state, PRNG_PHASE);
|
|
float rscatter = path_state_rng_1D_for_decision(kg, rng, state, PRNG_SCATTER_DISTANCE);
|
|
|
|
VolumeIntegrateResult result = kernel_volume_decoupled_scatter(kg,
|
|
state, ray, sd, &tp, rphase, rscatter, segment, (ls.t != FLT_MAX)? &ls.P: NULL, false);
|
|
|
|
(void)result;
|
|
kernel_assert(result == VOLUME_PATH_SCATTERED);
|
|
|
|
/* todo: split up light_sample so we don't have to call it again with new position */
|
|
light_sample(kg, light_t, light_u, light_v, sd->time, sd->P, state->bounce, &ls);
|
|
|
|
if(ls.pdf == 0.0f)
|
|
return;
|
|
|
|
/* sample random light */
|
|
if(direct_emission(kg, sd, &ls, state, &light_ray, &L_light, &is_lamp)) {
|
|
/* trace shadow ray */
|
|
float3 shadow;
|
|
|
|
if(!shadow_blocked(kg, state, &light_ray, &shadow)) {
|
|
/* accumulate */
|
|
path_radiance_accum_light(L, tp, &L_light, shadow, 1.0f, state->bounce, is_lamp);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
#endif
|
|
|
|
CCL_NAMESPACE_END
|
|
|