forked from bartvdbraak/blender
099aaea447
Code there started becoming a bit too big, by splitting it up it'll make it easier to do improvements or extending the features in there. The layout is not totally final yet, would need to try de-duplicating parts of code from split kernel with non-split integrators,
707 lines
21 KiB
C
707 lines
21 KiB
C
/*
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* Copyright 2011-2013 Blender Foundation
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifdef __OSL__
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#include "osl_shader.h"
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#endif
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#include "kernel_random.h"
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#include "kernel_projection.h"
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#include "kernel_montecarlo.h"
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#include "kernel_differential.h"
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#include "kernel_camera.h"
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#include "geom/geom.h"
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#include "kernel_accumulate.h"
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#include "kernel_shader.h"
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#include "kernel_light.h"
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#include "kernel_passes.h"
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#ifdef __SUBSURFACE__
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#include "kernel_subsurface.h"
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#endif
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#ifdef __VOLUME__
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#include "kernel_volume.h"
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#endif
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#include "kernel_path_state.h"
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#include "kernel_shadow.h"
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#include "kernel_emission.h"
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#include "kernel_path_common.h"
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#include "kernel_path_surface.h"
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#include "kernel_path_volume.h"
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#ifdef __KERNEL_DEBUG__
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#include "kernel_debug.h"
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#endif
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CCL_NAMESPACE_BEGIN
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ccl_device void kernel_path_indirect(KernelGlobals *kg, RNG *rng, Ray ray,
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float3 throughput, int num_samples, PathState state, PathRadiance *L)
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{
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/* path iteration */
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for(;;) {
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/* intersect scene */
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Intersection isect;
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uint visibility = path_state_ray_visibility(kg, &state);
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bool hit = scene_intersect(kg, &ray, visibility, &isect, NULL, 0.0f, 0.0f);
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#ifdef __LAMP_MIS__
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if(kernel_data.integrator.use_lamp_mis && !(state.flag & PATH_RAY_CAMERA)) {
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/* ray starting from previous non-transparent bounce */
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Ray light_ray;
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light_ray.P = ray.P - state.ray_t*ray.D;
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state.ray_t += isect.t;
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light_ray.D = ray.D;
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light_ray.t = state.ray_t;
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light_ray.time = ray.time;
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light_ray.dD = ray.dD;
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light_ray.dP = ray.dP;
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/* intersect with lamp */
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float3 emission;
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if(indirect_lamp_emission(kg, &state, &light_ray, &emission))
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path_radiance_accum_emission(L, throughput, emission, state.bounce);
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}
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#endif
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#ifdef __VOLUME__
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/* volume attenuation, emission, scatter */
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if(state.volume_stack[0].shader != SHADER_NONE) {
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Ray volume_ray = ray;
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volume_ray.t = (hit)? isect.t: FLT_MAX;
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bool heterogeneous = volume_stack_is_heterogeneous(kg, state.volume_stack);
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#ifdef __VOLUME_DECOUPLED__
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int sampling_method = volume_stack_sampling_method(kg, state.volume_stack);
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bool decoupled = kernel_volume_use_decoupled(kg, heterogeneous, false, sampling_method);
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if(decoupled) {
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/* cache steps along volume for repeated sampling */
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VolumeSegment volume_segment;
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ShaderData volume_sd;
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shader_setup_from_volume(kg, &volume_sd, &volume_ray, state.bounce, state.transparent_bounce);
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kernel_volume_decoupled_record(kg, &state,
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&volume_ray, &volume_sd, &volume_segment, heterogeneous);
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volume_segment.sampling_method = sampling_method;
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/* emission */
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if(volume_segment.closure_flag & SD_EMISSION)
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path_radiance_accum_emission(L, throughput, volume_segment.accum_emission, state.bounce);
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/* scattering */
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VolumeIntegrateResult result = VOLUME_PATH_ATTENUATED;
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if(volume_segment.closure_flag & SD_SCATTER) {
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bool all = kernel_data.integrator.sample_all_lights_indirect;
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/* direct light sampling */
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kernel_branched_path_volume_connect_light(kg, rng, &volume_sd,
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throughput, &state, L, all, &volume_ray, &volume_segment);
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/* indirect sample. if we use distance sampling and take just
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* one sample for direct and indirect light, we could share
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* this computation, but makes code a bit complex */
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float rphase = path_state_rng_1D_for_decision(kg, rng, &state, PRNG_PHASE);
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float rscatter = path_state_rng_1D_for_decision(kg, rng, &state, PRNG_SCATTER_DISTANCE);
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result = kernel_volume_decoupled_scatter(kg,
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&state, &volume_ray, &volume_sd, &throughput,
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rphase, rscatter, &volume_segment, NULL, true);
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}
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/* free cached steps */
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kernel_volume_decoupled_free(kg, &volume_segment);
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if(result == VOLUME_PATH_SCATTERED) {
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if(kernel_path_volume_bounce(kg, rng, &volume_sd, &throughput, &state, L, &ray))
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continue;
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else
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break;
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}
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else {
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throughput *= volume_segment.accum_transmittance;
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}
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}
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else
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#endif
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{
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/* integrate along volume segment with distance sampling */
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ShaderData volume_sd;
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VolumeIntegrateResult result = kernel_volume_integrate(
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kg, &state, &volume_sd, &volume_ray, L, &throughput, rng, heterogeneous);
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#ifdef __VOLUME_SCATTER__
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if(result == VOLUME_PATH_SCATTERED) {
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/* direct lighting */
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kernel_path_volume_connect_light(kg, rng, &volume_sd, throughput, &state, L);
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/* indirect light bounce */
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if(kernel_path_volume_bounce(kg, rng, &volume_sd, &throughput, &state, L, &ray))
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continue;
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else
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break;
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}
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#endif
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}
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}
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#endif
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if(!hit) {
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#ifdef __BACKGROUND__
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/* sample background shader */
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float3 L_background = indirect_background(kg, &state, &ray);
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path_radiance_accum_background(L, throughput, L_background, state.bounce);
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#endif
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break;
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}
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/* setup shading */
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ShaderData sd;
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shader_setup_from_ray(kg, &sd, &isect, &ray, state.bounce, state.transparent_bounce);
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float rbsdf = path_state_rng_1D_for_decision(kg, rng, &state, PRNG_BSDF);
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shader_eval_surface(kg, &sd, rbsdf, state.flag, SHADER_CONTEXT_INDIRECT);
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#ifdef __BRANCHED_PATH__
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shader_merge_closures(&sd);
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#endif
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/* blurring of bsdf after bounces, for rays that have a small likelihood
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* of following this particular path (diffuse, rough glossy) */
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if(kernel_data.integrator.filter_glossy != FLT_MAX) {
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float blur_pdf = kernel_data.integrator.filter_glossy*state.min_ray_pdf;
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if(blur_pdf < 1.0f) {
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float blur_roughness = sqrtf(1.0f - blur_pdf)*0.5f;
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shader_bsdf_blur(kg, &sd, blur_roughness);
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}
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}
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#ifdef __EMISSION__
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/* emission */
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if(sd.flag & SD_EMISSION) {
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float3 emission = indirect_primitive_emission(kg, &sd, isect.t, state.flag, state.ray_pdf);
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path_radiance_accum_emission(L, throughput, emission, state.bounce);
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}
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#endif
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/* path termination. this is a strange place to put the termination, it's
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* mainly due to the mixed in MIS that we use. gives too many unneeded
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* shader evaluations, only need emission if we are going to terminate */
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float probability = path_state_terminate_probability(kg, &state, throughput*num_samples);
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if(probability == 0.0f) {
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break;
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}
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else if(probability != 1.0f) {
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float terminate = path_state_rng_1D_for_decision(kg, rng, &state, PRNG_TERMINATE);
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if(terminate >= probability)
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break;
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throughput /= probability;
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}
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#ifdef __AO__
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/* ambient occlusion */
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if(kernel_data.integrator.use_ambient_occlusion || (sd.flag & SD_AO)) {
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float bsdf_u, bsdf_v;
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path_state_rng_2D(kg, rng, &state, PRNG_BSDF_U, &bsdf_u, &bsdf_v);
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float ao_factor = kernel_data.background.ao_factor;
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float3 ao_N;
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float3 ao_bsdf = shader_bsdf_ao(kg, &sd, ao_factor, &ao_N);
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float3 ao_D;
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float ao_pdf;
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float3 ao_alpha = make_float3(0.0f, 0.0f, 0.0f);
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sample_cos_hemisphere(ao_N, bsdf_u, bsdf_v, &ao_D, &ao_pdf);
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if(dot(sd.Ng, ao_D) > 0.0f && ao_pdf != 0.0f) {
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Ray light_ray;
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float3 ao_shadow;
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light_ray.P = ray_offset(sd.P, sd.Ng);
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light_ray.D = ao_D;
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light_ray.t = kernel_data.background.ao_distance;
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#ifdef __OBJECT_MOTION__
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light_ray.time = sd.time;
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#endif
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light_ray.dP = sd.dP;
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light_ray.dD = differential3_zero();
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if(!shadow_blocked(kg, &state, &light_ray, &ao_shadow))
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path_radiance_accum_ao(L, throughput, ao_alpha, ao_bsdf, ao_shadow, state.bounce);
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}
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}
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#endif
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#ifdef __SUBSURFACE__
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/* bssrdf scatter to a different location on the same object, replacing
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* the closures with a diffuse BSDF */
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if(sd.flag & SD_BSSRDF) {
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float bssrdf_probability;
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ShaderClosure *sc = subsurface_scatter_pick_closure(kg, &sd, &bssrdf_probability);
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/* modify throughput for picking bssrdf or bsdf */
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throughput *= bssrdf_probability;
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/* do bssrdf scatter step if we picked a bssrdf closure */
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if(sc) {
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uint lcg_state = lcg_state_init(rng, &state, 0x68bc21eb);
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float bssrdf_u, bssrdf_v;
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path_state_rng_2D(kg, rng, &state, PRNG_BSDF_U, &bssrdf_u, &bssrdf_v);
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subsurface_scatter_step(kg, &sd, state.flag, sc, &lcg_state, bssrdf_u, bssrdf_v, false);
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}
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}
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#endif
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#if defined(__EMISSION__) && defined(__BRANCHED_PATH__)
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if(kernel_data.integrator.use_direct_light) {
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bool all = kernel_data.integrator.sample_all_lights_indirect;
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kernel_branched_path_surface_connect_light(kg, rng, &sd, &state, throughput, 1.0f, L, all);
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}
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#endif
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if(!kernel_path_surface_bounce(kg, rng, &sd, &throughput, &state, L, &ray))
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break;
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}
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}
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ccl_device void kernel_path_ao(KernelGlobals *kg, ShaderData *sd, PathRadiance *L, PathState *state, RNG *rng, float3 throughput)
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{
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/* todo: solve correlation */
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float bsdf_u, bsdf_v;
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path_state_rng_2D(kg, rng, state, PRNG_BSDF_U, &bsdf_u, &bsdf_v);
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float ao_factor = kernel_data.background.ao_factor;
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float3 ao_N;
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float3 ao_bsdf = shader_bsdf_ao(kg, sd, ao_factor, &ao_N);
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float3 ao_D;
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float ao_pdf;
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float3 ao_alpha = shader_bsdf_alpha(kg, sd);
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sample_cos_hemisphere(ao_N, bsdf_u, bsdf_v, &ao_D, &ao_pdf);
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if(dot(ccl_fetch(sd, Ng), ao_D) > 0.0f && ao_pdf != 0.0f) {
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Ray light_ray;
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float3 ao_shadow;
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light_ray.P = ray_offset(ccl_fetch(sd, P), ccl_fetch(sd, Ng));
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light_ray.D = ao_D;
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light_ray.t = kernel_data.background.ao_distance;
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#ifdef __OBJECT_MOTION__
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light_ray.time = ccl_fetch(sd, time);
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#endif
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light_ray.dP = ccl_fetch(sd, dP);
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light_ray.dD = differential3_zero();
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if(!shadow_blocked(kg, state, &light_ray, &ao_shadow))
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path_radiance_accum_ao(L, throughput, ao_alpha, ao_bsdf, ao_shadow, state->bounce);
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}
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}
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#ifdef __SUBSURFACE__
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ccl_device bool kernel_path_subsurface_scatter(KernelGlobals *kg, ShaderData *sd, PathRadiance *L, PathState *state, RNG *rng, Ray *ray, float3 *throughput)
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{
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float bssrdf_probability;
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ShaderClosure *sc = subsurface_scatter_pick_closure(kg, sd, &bssrdf_probability);
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/* modify throughput for picking bssrdf or bsdf */
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*throughput *= bssrdf_probability;
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/* do bssrdf scatter step if we picked a bssrdf closure */
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if(sc) {
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uint lcg_state = lcg_state_init(rng, state, 0x68bc21eb);
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ShaderData bssrdf_sd[BSSRDF_MAX_HITS];
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float bssrdf_u, bssrdf_v;
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path_state_rng_2D(kg, rng, state, PRNG_BSDF_U, &bssrdf_u, &bssrdf_v);
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int num_hits = subsurface_scatter_multi_step(kg, sd, bssrdf_sd, state->flag, sc, &lcg_state, bssrdf_u, bssrdf_v, false);
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#ifdef __VOLUME__
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Ray volume_ray = *ray;
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bool need_update_volume_stack = kernel_data.integrator.use_volumes &&
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ccl_fetch(sd, flag) & SD_OBJECT_INTERSECTS_VOLUME;
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#endif
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/* compute lighting with the BSDF closure */
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for(int hit = 0; hit < num_hits; hit++) {
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float3 tp = *throughput;
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PathState hit_state = *state;
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Ray hit_ray = *ray;
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hit_state.rng_offset += PRNG_BOUNCE_NUM;
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kernel_path_surface_connect_light(kg, rng, &bssrdf_sd[hit], tp, state, L);
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if(kernel_path_surface_bounce(kg, rng, &bssrdf_sd[hit], &tp, &hit_state, L, &hit_ray)) {
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#ifdef __LAMP_MIS__
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hit_state.ray_t = 0.0f;
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#endif
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#ifdef __VOLUME__
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if(need_update_volume_stack) {
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/* Setup ray from previous surface point to the new one. */
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volume_ray.D = normalize_len(hit_ray.P - volume_ray.P,
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&volume_ray.t);
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kernel_volume_stack_update_for_subsurface(
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kg,
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&volume_ray,
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hit_state.volume_stack);
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/* Move volume ray forward. */
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volume_ray.P = hit_ray.P;
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}
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#endif
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kernel_path_indirect(kg, rng, hit_ray, tp, state->num_samples, hit_state, L);
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/* for render passes, sum and reset indirect light pass variables
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* for the next samples */
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path_radiance_sum_indirect(L);
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path_radiance_reset_indirect(L);
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}
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}
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return true;
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}
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return false;
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}
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#endif
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ccl_device float4 kernel_path_integrate(KernelGlobals *kg, RNG *rng, int sample, Ray ray, ccl_global float *buffer)
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{
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/* initialize */
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PathRadiance L;
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float3 throughput = make_float3(1.0f, 1.0f, 1.0f);
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float L_transparent = 0.0f;
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path_radiance_init(&L, kernel_data.film.use_light_pass);
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PathState state;
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path_state_init(kg, &state, rng, sample, &ray);
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#ifdef __KERNEL_DEBUG__
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DebugData debug_data;
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debug_data_init(&debug_data);
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#endif
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/* path iteration */
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for(;;) {
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/* intersect scene */
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Intersection isect;
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uint visibility = path_state_ray_visibility(kg, &state);
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#ifdef __HAIR__
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float difl = 0.0f, extmax = 0.0f;
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uint lcg_state = 0;
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if(kernel_data.bvh.have_curves) {
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if((kernel_data.cam.resolution == 1) && (state.flag & PATH_RAY_CAMERA)) {
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float3 pixdiff = ray.dD.dx + ray.dD.dy;
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/*pixdiff = pixdiff - dot(pixdiff, ray.D)*ray.D;*/
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difl = kernel_data.curve.minimum_width * len(pixdiff) * 0.5f;
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}
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extmax = kernel_data.curve.maximum_width;
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lcg_state = lcg_state_init(rng, &state, 0x51633e2d);
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}
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bool hit = scene_intersect(kg, &ray, visibility, &isect, &lcg_state, difl, extmax);
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#else
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bool hit = scene_intersect(kg, &ray, visibility, &isect, NULL, 0.0f, 0.0f);
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#endif
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#ifdef __KERNEL_DEBUG__
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if(state.flag & PATH_RAY_CAMERA) {
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debug_data.num_bvh_traversal_steps += isect.num_traversal_steps;
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debug_data.num_bvh_traversed_instances += isect.num_traversed_instances;
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}
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debug_data.num_ray_bounces++;
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#endif
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#ifdef __LAMP_MIS__
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if(kernel_data.integrator.use_lamp_mis && !(state.flag & PATH_RAY_CAMERA)) {
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/* ray starting from previous non-transparent bounce */
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Ray light_ray;
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light_ray.P = ray.P - state.ray_t*ray.D;
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state.ray_t += isect.t;
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light_ray.D = ray.D;
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light_ray.t = state.ray_t;
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light_ray.time = ray.time;
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light_ray.dD = ray.dD;
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light_ray.dP = ray.dP;
|
|
|
|
/* intersect with lamp */
|
|
float3 emission;
|
|
|
|
if(indirect_lamp_emission(kg, &state, &light_ray, &emission))
|
|
path_radiance_accum_emission(&L, throughput, emission, state.bounce);
|
|
}
|
|
#endif
|
|
|
|
#ifdef __VOLUME__
|
|
/* volume attenuation, emission, scatter */
|
|
if(state.volume_stack[0].shader != SHADER_NONE) {
|
|
Ray volume_ray = ray;
|
|
volume_ray.t = (hit)? isect.t: FLT_MAX;
|
|
|
|
bool heterogeneous = volume_stack_is_heterogeneous(kg, state.volume_stack);
|
|
|
|
#ifdef __VOLUME_DECOUPLED__
|
|
int sampling_method = volume_stack_sampling_method(kg, state.volume_stack);
|
|
bool decoupled = kernel_volume_use_decoupled(kg, heterogeneous, true, sampling_method);
|
|
|
|
if(decoupled) {
|
|
/* cache steps along volume for repeated sampling */
|
|
VolumeSegment volume_segment;
|
|
ShaderData volume_sd;
|
|
|
|
shader_setup_from_volume(kg, &volume_sd, &volume_ray, state.bounce, state.transparent_bounce);
|
|
kernel_volume_decoupled_record(kg, &state,
|
|
&volume_ray, &volume_sd, &volume_segment, heterogeneous);
|
|
|
|
volume_segment.sampling_method = sampling_method;
|
|
|
|
/* emission */
|
|
if(volume_segment.closure_flag & SD_EMISSION)
|
|
path_radiance_accum_emission(&L, throughput, volume_segment.accum_emission, state.bounce);
|
|
|
|
/* scattering */
|
|
VolumeIntegrateResult result = VOLUME_PATH_ATTENUATED;
|
|
|
|
if(volume_segment.closure_flag & SD_SCATTER) {
|
|
bool all = false;
|
|
|
|
/* direct light sampling */
|
|
kernel_branched_path_volume_connect_light(kg, rng, &volume_sd,
|
|
throughput, &state, &L, all, &volume_ray, &volume_segment);
|
|
|
|
/* indirect sample. if we use distance sampling and take just
|
|
* one sample for direct and indirect light, we could share
|
|
* this computation, but makes code a bit complex */
|
|
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);
|
|
|
|
result = kernel_volume_decoupled_scatter(kg,
|
|
&state, &volume_ray, &volume_sd, &throughput,
|
|
rphase, rscatter, &volume_segment, NULL, true);
|
|
}
|
|
|
|
/* free cached steps */
|
|
kernel_volume_decoupled_free(kg, &volume_segment);
|
|
|
|
if(result == VOLUME_PATH_SCATTERED) {
|
|
if(kernel_path_volume_bounce(kg, rng, &volume_sd, &throughput, &state, &L, &ray))
|
|
continue;
|
|
else
|
|
break;
|
|
}
|
|
else {
|
|
throughput *= volume_segment.accum_transmittance;
|
|
}
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
/* integrate along volume segment with distance sampling */
|
|
ShaderData volume_sd;
|
|
VolumeIntegrateResult result = kernel_volume_integrate(
|
|
kg, &state, &volume_sd, &volume_ray, &L, &throughput, rng, heterogeneous);
|
|
|
|
#ifdef __VOLUME_SCATTER__
|
|
if(result == VOLUME_PATH_SCATTERED) {
|
|
/* direct lighting */
|
|
kernel_path_volume_connect_light(kg, rng, &volume_sd, throughput, &state, &L);
|
|
|
|
/* indirect light bounce */
|
|
if(kernel_path_volume_bounce(kg, rng, &volume_sd, &throughput, &state, &L, &ray))
|
|
continue;
|
|
else
|
|
break;
|
|
}
|
|
#endif
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if(!hit) {
|
|
/* eval background shader if nothing hit */
|
|
if(kernel_data.background.transparent && (state.flag & PATH_RAY_CAMERA)) {
|
|
L_transparent += average(throughput);
|
|
|
|
#ifdef __PASSES__
|
|
if(!(kernel_data.film.pass_flag & PASS_BACKGROUND))
|
|
#endif
|
|
break;
|
|
}
|
|
|
|
#ifdef __BACKGROUND__
|
|
/* sample background shader */
|
|
float3 L_background = indirect_background(kg, &state, &ray);
|
|
path_radiance_accum_background(&L, throughput, L_background, state.bounce);
|
|
#endif
|
|
|
|
break;
|
|
}
|
|
|
|
/* setup shading */
|
|
ShaderData sd;
|
|
shader_setup_from_ray(kg, &sd, &isect, &ray, state.bounce, state.transparent_bounce);
|
|
float rbsdf = path_state_rng_1D_for_decision(kg, rng, &state, PRNG_BSDF);
|
|
shader_eval_surface(kg, &sd, rbsdf, state.flag, SHADER_CONTEXT_MAIN);
|
|
|
|
/* holdout */
|
|
#ifdef __HOLDOUT__
|
|
if((sd.flag & (SD_HOLDOUT|SD_HOLDOUT_MASK)) && (state.flag & PATH_RAY_CAMERA)) {
|
|
if(kernel_data.background.transparent) {
|
|
float3 holdout_weight;
|
|
|
|
if(sd.flag & SD_HOLDOUT_MASK)
|
|
holdout_weight = make_float3(1.0f, 1.0f, 1.0f);
|
|
else
|
|
holdout_weight = shader_holdout_eval(kg, &sd);
|
|
|
|
/* any throughput is ok, should all be identical here */
|
|
L_transparent += average(holdout_weight*throughput);
|
|
}
|
|
|
|
if(sd.flag & SD_HOLDOUT_MASK)
|
|
break;
|
|
}
|
|
#endif
|
|
|
|
/* holdout mask objects do not write data passes */
|
|
kernel_write_data_passes(kg, buffer, &L, &sd, sample, &state, throughput);
|
|
|
|
/* blurring of bsdf after bounces, for rays that have a small likelihood
|
|
* of following this particular path (diffuse, rough glossy) */
|
|
if(kernel_data.integrator.filter_glossy != FLT_MAX) {
|
|
float blur_pdf = kernel_data.integrator.filter_glossy*state.min_ray_pdf;
|
|
|
|
if(blur_pdf < 1.0f) {
|
|
float blur_roughness = sqrtf(1.0f - blur_pdf)*0.5f;
|
|
shader_bsdf_blur(kg, &sd, blur_roughness);
|
|
}
|
|
}
|
|
|
|
#ifdef __EMISSION__
|
|
/* emission */
|
|
if(sd.flag & SD_EMISSION) {
|
|
/* todo: is isect.t wrong here for transparent surfaces? */
|
|
float3 emission = indirect_primitive_emission(kg, &sd, isect.t, state.flag, state.ray_pdf);
|
|
path_radiance_accum_emission(&L, throughput, emission, state.bounce);
|
|
}
|
|
#endif
|
|
|
|
/* path termination. this is a strange place to put the termination, it's
|
|
* mainly due to the mixed in MIS that we use. gives too many unneeded
|
|
* shader evaluations, only need emission if we are going to terminate */
|
|
float probability = path_state_terminate_probability(kg, &state, throughput);
|
|
|
|
if(probability == 0.0f) {
|
|
break;
|
|
}
|
|
else if(probability != 1.0f) {
|
|
float terminate = path_state_rng_1D_for_decision(kg, rng, &state, PRNG_TERMINATE);
|
|
|
|
if(terminate >= probability)
|
|
break;
|
|
|
|
throughput /= probability;
|
|
}
|
|
|
|
#ifdef __AO__
|
|
/* ambient occlusion */
|
|
if(kernel_data.integrator.use_ambient_occlusion || (sd.flag & SD_AO)) {
|
|
kernel_path_ao(kg, &sd, &L, &state, rng, throughput);
|
|
}
|
|
#endif
|
|
|
|
#ifdef __SUBSURFACE__
|
|
/* bssrdf scatter to a different location on the same object, replacing
|
|
* the closures with a diffuse BSDF */
|
|
if(sd.flag & SD_BSSRDF) {
|
|
if(kernel_path_subsurface_scatter(kg, &sd, &L, &state, rng, &ray, &throughput))
|
|
break;
|
|
}
|
|
#endif
|
|
|
|
/* direct lighting */
|
|
kernel_path_surface_connect_light(kg, rng, &sd, throughput, &state, &L);
|
|
|
|
/* compute direct lighting and next bounce */
|
|
if(!kernel_path_surface_bounce(kg, rng, &sd, &throughput, &state, &L, &ray))
|
|
break;
|
|
}
|
|
|
|
float3 L_sum = path_radiance_clamp_and_sum(kg, &L);
|
|
|
|
kernel_write_light_passes(kg, buffer, &L, sample);
|
|
|
|
#ifdef __KERNEL_DEBUG__
|
|
kernel_write_debug_passes(kg, buffer, &state, &debug_data, sample);
|
|
#endif
|
|
|
|
return make_float4(L_sum.x, L_sum.y, L_sum.z, 1.0f - L_transparent);
|
|
}
|
|
|
|
ccl_device void kernel_path_trace(KernelGlobals *kg,
|
|
ccl_global float *buffer, ccl_global uint *rng_state,
|
|
int sample, int x, int y, int offset, int stride)
|
|
{
|
|
/* buffer offset */
|
|
int index = offset + x + y*stride;
|
|
int pass_stride = kernel_data.film.pass_stride;
|
|
|
|
rng_state += index;
|
|
buffer += index*pass_stride;
|
|
|
|
/* initialize random numbers and ray */
|
|
RNG rng;
|
|
Ray ray;
|
|
|
|
kernel_path_trace_setup(kg, rng_state, sample, x, y, &rng, &ray);
|
|
|
|
/* integrate */
|
|
float4 L;
|
|
|
|
if(ray.t != 0.0f)
|
|
L = kernel_path_integrate(kg, &rng, sample, ray, buffer);
|
|
else
|
|
L = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
|
|
|
|
/* accumulate result in output buffer */
|
|
kernel_write_pass_float4(buffer, sample, L);
|
|
|
|
path_rng_end(kg, rng_state, rng);
|
|
}
|
|
|
|
CCL_NAMESPACE_END
|
|
|