forked from bartvdbraak/blender
b20a7e01d0
instead of sobol. So far one doesn't seem to be consistently better or worse than the other for the same number of samples but more testing is needed. The random number generator itself is slower than sobol for most number of samples, except 16, 64, 256, .. because they can be computed faster. This can probably be optimized, but we can do that when/if this actually turns out to be useful. Paper this implementation is based on: http://graphics.pixar.com/library/MultiJitteredSampling/ Also includes some refactoring of RNG code, fixing a Sobol correlation issue with the first BSDF and < 16 samples, skipping some unneeded RNG calls and using a simpler unit square to unit disk function.
1204 lines
35 KiB
C
1204 lines
35 KiB
C
/*
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* Copyright 2011, Blender Foundation.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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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_differential.h"
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#include "kernel_montecarlo.h"
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#include "kernel_projection.h"
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#include "kernel_object.h"
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#include "kernel_triangle.h"
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#include "kernel_curve.h"
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#include "kernel_primitive.h"
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#include "kernel_projection.h"
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#include "kernel_random.h"
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#include "kernel_bvh.h"
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#include "kernel_accumulate.h"
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#include "kernel_camera.h"
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#include "kernel_shader.h"
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#include "kernel_light.h"
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#include "kernel_emission.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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CCL_NAMESPACE_BEGIN
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typedef struct PathState {
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int flag;
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int bounce;
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int diffuse_bounce;
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int glossy_bounce;
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int transmission_bounce;
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int transparent_bounce;
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} PathState;
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__device_inline void path_state_init(PathState *state)
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{
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state->flag = PATH_RAY_CAMERA|PATH_RAY_SINGULAR|PATH_RAY_MIS_SKIP;
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state->bounce = 0;
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state->diffuse_bounce = 0;
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state->glossy_bounce = 0;
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state->transmission_bounce = 0;
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state->transparent_bounce = 0;
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}
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__device_inline void path_state_next(KernelGlobals *kg, PathState *state, int label)
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{
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/* ray through transparent keeps same flags from previous ray and is
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* not counted as a regular bounce, transparent has separate max */
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if(label & LABEL_TRANSPARENT) {
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state->flag |= PATH_RAY_TRANSPARENT;
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state->transparent_bounce++;
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if(!kernel_data.integrator.transparent_shadows)
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state->flag |= PATH_RAY_MIS_SKIP;
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return;
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}
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state->bounce++;
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/* reflection/transmission */
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if(label & LABEL_REFLECT) {
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state->flag |= PATH_RAY_REFLECT;
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state->flag &= ~(PATH_RAY_TRANSMIT|PATH_RAY_CAMERA|PATH_RAY_TRANSPARENT);
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if(label & LABEL_DIFFUSE)
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state->diffuse_bounce++;
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else
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state->glossy_bounce++;
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}
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else {
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kernel_assert(label & LABEL_TRANSMIT);
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state->flag |= PATH_RAY_TRANSMIT;
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state->flag &= ~(PATH_RAY_REFLECT|PATH_RAY_CAMERA|PATH_RAY_TRANSPARENT);
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state->transmission_bounce++;
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}
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/* diffuse/glossy/singular */
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if(label & LABEL_DIFFUSE) {
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state->flag |= PATH_RAY_DIFFUSE;
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state->flag &= ~(PATH_RAY_GLOSSY|PATH_RAY_SINGULAR|PATH_RAY_MIS_SKIP);
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}
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else if(label & LABEL_GLOSSY) {
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state->flag |= PATH_RAY_GLOSSY;
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state->flag &= ~(PATH_RAY_DIFFUSE|PATH_RAY_SINGULAR|PATH_RAY_MIS_SKIP);
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}
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else {
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kernel_assert(label & LABEL_SINGULAR);
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state->flag |= PATH_RAY_GLOSSY|PATH_RAY_SINGULAR|PATH_RAY_MIS_SKIP;
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state->flag &= ~PATH_RAY_DIFFUSE;
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}
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}
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__device_inline uint path_state_ray_visibility(KernelGlobals *kg, PathState *state)
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{
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uint flag = state->flag;
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/* for visibility, diffuse/glossy are for reflection only */
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if(flag & PATH_RAY_TRANSMIT)
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flag &= ~(PATH_RAY_DIFFUSE|PATH_RAY_GLOSSY);
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/* for camera visibility, use render layer flags */
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if(flag & PATH_RAY_CAMERA)
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flag |= kernel_data.integrator.layer_flag;
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return flag;
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}
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__device_inline float path_state_terminate_probability(KernelGlobals *kg, PathState *state, const float3 throughput)
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{
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if(state->flag & PATH_RAY_TRANSPARENT) {
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/* transparent rays treated separately */
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if(state->transparent_bounce >= kernel_data.integrator.transparent_max_bounce)
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return 0.0f;
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else if(state->transparent_bounce <= kernel_data.integrator.transparent_min_bounce)
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return 1.0f;
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}
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else {
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/* other rays */
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if((state->bounce >= kernel_data.integrator.max_bounce) ||
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(state->diffuse_bounce >= kernel_data.integrator.max_diffuse_bounce) ||
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(state->glossy_bounce >= kernel_data.integrator.max_glossy_bounce) ||
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(state->transmission_bounce >= kernel_data.integrator.max_transmission_bounce))
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{
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return 0.0f;
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}
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else if(state->bounce <= kernel_data.integrator.min_bounce) {
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return 1.0f;
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}
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}
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/* probalistic termination */
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return average(throughput); /* todo: try using max here */
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}
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__device_inline bool shadow_blocked(KernelGlobals *kg, PathState *state, Ray *ray, float3 *shadow)
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{
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*shadow = make_float3(1.0f, 1.0f, 1.0f);
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if(ray->t == 0.0f)
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return false;
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Intersection isect;
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#ifdef __HAIR__
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bool result = scene_intersect(kg, ray, PATH_RAY_SHADOW_OPAQUE, &isect, NULL, 0.0f, 0.0f);
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#else
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bool result = scene_intersect(kg, ray, PATH_RAY_SHADOW_OPAQUE, &isect);
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#endif
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#ifdef __TRANSPARENT_SHADOWS__
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if(result && kernel_data.integrator.transparent_shadows) {
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/* transparent shadows work in such a way to try to minimize overhead
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* in cases where we don't need them. after a regular shadow ray is
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* cast we check if the hit primitive was potentially transparent, and
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* only in that case start marching. this gives on extra ray cast for
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* the cases were we do want transparency.
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*
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* also note that for this to work correct, multi close sampling must
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* be used, since we don't pass a random number to shader_eval_surface */
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if(shader_transparent_shadow(kg, &isect)) {
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float3 throughput = make_float3(1.0f, 1.0f, 1.0f);
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float3 Pend = ray->P + ray->D*ray->t;
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int bounce = state->transparent_bounce;
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for(;;) {
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if(bounce >= kernel_data.integrator.transparent_max_bounce) {
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return true;
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}
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else if(bounce >= kernel_data.integrator.transparent_min_bounce) {
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/* todo: get random number somewhere for probabilistic terminate */
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#if 0
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float probability = average(throughput);
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float terminate = 0.0f;
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if(terminate >= probability)
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return true;
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throughput /= probability;
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#endif
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}
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#ifdef __HAIR__
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if(!scene_intersect(kg, ray, PATH_RAY_SHADOW_TRANSPARENT, &isect, NULL, 0.0f, 0.0f)) {
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#else
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if(!scene_intersect(kg, ray, PATH_RAY_SHADOW_TRANSPARENT, &isect)) {
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#endif
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*shadow *= throughput;
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return false;
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}
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if(!shader_transparent_shadow(kg, &isect))
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return true;
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ShaderData sd;
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shader_setup_from_ray(kg, &sd, &isect, ray);
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shader_eval_surface(kg, &sd, 0.0f, PATH_RAY_SHADOW, SHADER_CONTEXT_SHADOW);
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throughput *= shader_bsdf_transparency(kg, &sd);
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ray->P = ray_offset(sd.P, -sd.Ng);
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if(ray->t != FLT_MAX)
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ray->D = normalize_len(Pend - ray->P, &ray->t);
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bounce++;
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}
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}
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}
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#endif
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return result;
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}
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__device float4 kernel_path_progressive(KernelGlobals *kg, RNG rng, int sample, Ray ray, __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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float min_ray_pdf = FLT_MAX;
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float ray_pdf = 0.0f;
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#ifdef __LAMP_MIS__
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float ray_t = 0.0f;
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#endif
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PathState state;
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int rng_offset = PRNG_BASE_NUM;
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int num_samples = kernel_data.integrator.aa_samples;
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path_state_init(&state);
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/* path iteration */
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for(;; rng_offset += PRNG_BOUNCE_NUM) {
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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_kernel_data.minimum_width * len(pixdiff) * 0.5f;
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}
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extmax = kernel_data.curve_kernel_data.maximum_width;
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lcg_state = lcg_init(rng + rng_offset + sample*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);
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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 - ray_t*ray.D;
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ray_t += isect.t;
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light_ray.D = ray.D;
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light_ray.t = 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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float light_t = path_rng_1D(kg, rng, sample, num_samples, rng_offset + PRNG_LIGHT);
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float3 emission;
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if(indirect_lamp_emission(kg, &light_ray, state.flag, ray_pdf, light_t, &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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if(!hit) {
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/* eval background shader if nothing hit */
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if(kernel_data.background.transparent && (state.flag & PATH_RAY_CAMERA)) {
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L_transparent += average(throughput);
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#ifdef __PASSES__
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if(!(kernel_data.film.pass_flag & PASS_BACKGROUND))
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#endif
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break;
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}
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#ifdef __BACKGROUND__
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/* sample background shader */
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float3 L_background = indirect_background(kg, &ray, state.flag, ray_pdf);
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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);
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float rbsdf = path_rng_1D(kg, rng, sample, num_samples, rng_offset + PRNG_BSDF);
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shader_eval_surface(kg, &sd, rbsdf, state.flag, SHADER_CONTEXT_MAIN);
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/* holdout */
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#ifdef __HOLDOUT__
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if((sd.flag & (SD_HOLDOUT|SD_HOLDOUT_MASK)) && (state.flag & PATH_RAY_CAMERA)) {
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if(kernel_data.background.transparent) {
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float3 holdout_weight;
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if(sd.flag & SD_HOLDOUT_MASK)
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holdout_weight = make_float3(1.0f, 1.0f, 1.0f);
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else
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holdout_weight = shader_holdout_eval(kg, &sd);
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/* any throughput is ok, should all be identical here */
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L_transparent += average(holdout_weight*throughput);
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}
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if(sd.flag & SD_HOLDOUT_MASK)
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break;
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}
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#endif
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/* holdout mask objects do not write data passes */
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kernel_write_data_passes(kg, buffer, &L, &sd, sample, state.flag, throughput);
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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*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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/* todo: is isect.t wrong here for transparent surfaces? */
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float3 emission = indirect_primitive_emission(kg, &sd, isect.t, state.flag, 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);
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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_rng_1D(kg, rng, sample, num_samples, rng_offset + 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 __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_init(rng + rng_offset + sample*0x68bc21eb);
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subsurface_scatter_step(kg, &sd, state.flag, sc, &lcg_state, false);
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}
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}
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#endif
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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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/* todo: solve correlation */
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float2 bsdf_uv = path_rng_2D(kg, rng, sample, num_samples, rng_offset + PRNG_BSDF_U);
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float bsdf_u = bsdf_uv.x;
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float bsdf_v = bsdf_uv.y;
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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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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_bsdf, ao_shadow, state.bounce);
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}
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}
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#endif
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#ifdef __EMISSION__
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if(kernel_data.integrator.use_direct_light) {
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/* sample illumination from lights to find path contribution */
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if(sd.flag & SD_BSDF_HAS_EVAL) {
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float light_t = path_rng_1D(kg, rng, sample, num_samples, rng_offset + PRNG_LIGHT);
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#ifdef __MULTI_CLOSURE__
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float light_o = 0.0f;
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#else
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float light_o = path_rng_1D(kg, rng, sample, num_samples, rng_offset + PRNG_LIGHT_F);
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#endif
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float2 light_uv = path_rng_2D(kg, rng, sample, num_samples, rng_offset + PRNG_LIGHT_U);
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float light_u = light_uv.x;
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float light_v = light_uv.y;
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Ray light_ray;
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BsdfEval L_light;
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bool is_lamp;
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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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if(direct_emission(kg, &sd, -1, light_t, light_o, light_u, light_v, &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
|
|
|
|
/* no BSDF? we can stop here */
|
|
if(!(sd.flag & SD_BSDF))
|
|
break;
|
|
|
|
/* sample BSDF */
|
|
float bsdf_pdf;
|
|
BsdfEval bsdf_eval;
|
|
float3 bsdf_omega_in;
|
|
differential3 bsdf_domega_in;
|
|
float2 bsdf_uv = path_rng_2D(kg, rng, sample, num_samples, rng_offset + PRNG_BSDF_U);
|
|
float bsdf_u = bsdf_uv.x;
|
|
float bsdf_v = bsdf_uv.y;
|
|
int label;
|
|
|
|
label = shader_bsdf_sample(kg, &sd, bsdf_u, bsdf_v, &bsdf_eval,
|
|
&bsdf_omega_in, &bsdf_domega_in, &bsdf_pdf);
|
|
|
|
if(bsdf_pdf == 0.0f || bsdf_eval_is_zero(&bsdf_eval))
|
|
break;
|
|
|
|
/* modify throughput */
|
|
path_radiance_bsdf_bounce(&L, &throughput, &bsdf_eval, bsdf_pdf, state.bounce, label);
|
|
|
|
/* set labels */
|
|
if(!(label & LABEL_TRANSPARENT)) {
|
|
ray_pdf = bsdf_pdf;
|
|
#ifdef __LAMP_MIS__
|
|
ray_t = 0.0f;
|
|
#endif
|
|
min_ray_pdf = fminf(bsdf_pdf, min_ray_pdf);
|
|
}
|
|
|
|
/* update path state */
|
|
path_state_next(kg, &state, label);
|
|
|
|
/* setup ray */
|
|
ray.P = ray_offset(sd.P, (label & LABEL_TRANSMIT)? -sd.Ng: sd.Ng);
|
|
ray.D = bsdf_omega_in;
|
|
|
|
if(state.bounce == 0)
|
|
ray.t -= sd.ray_length; /* clipping works through transparent */
|
|
else
|
|
ray.t = FLT_MAX;
|
|
|
|
#ifdef __RAY_DIFFERENTIALS__
|
|
ray.dP = sd.dP;
|
|
ray.dD = bsdf_domega_in;
|
|
#endif
|
|
}
|
|
|
|
float3 L_sum = path_radiance_sum(kg, &L);
|
|
|
|
#ifdef __CLAMP_SAMPLE__
|
|
path_radiance_clamp(&L, &L_sum, kernel_data.integrator.sample_clamp);
|
|
#endif
|
|
|
|
kernel_write_light_passes(kg, buffer, &L, sample);
|
|
|
|
return make_float4(L_sum.x, L_sum.y, L_sum.z, 1.0f - L_transparent);
|
|
}
|
|
|
|
#ifdef __NON_PROGRESSIVE__
|
|
|
|
__device void kernel_path_indirect(KernelGlobals *kg, RNG rng, int sample, Ray ray, __global float *buffer,
|
|
float3 throughput, int num_samples, int num_total_samples,
|
|
float min_ray_pdf, float ray_pdf, PathState state, int rng_offset, PathRadiance *L)
|
|
{
|
|
#ifdef __LAMP_MIS__
|
|
float ray_t = 0.0f;
|
|
#endif
|
|
|
|
/* path iteration */
|
|
for(;; rng_offset += PRNG_BOUNCE_NUM) {
|
|
/* intersect scene */
|
|
Intersection isect;
|
|
uint visibility = path_state_ray_visibility(kg, &state);
|
|
#ifdef __HAIR__
|
|
bool hit = scene_intersect(kg, &ray, visibility, &isect, NULL, 0.0f, 0.0f);
|
|
#else
|
|
bool hit = scene_intersect(kg, &ray, visibility, &isect);
|
|
#endif
|
|
|
|
#ifdef __LAMP_MIS__
|
|
if(kernel_data.integrator.use_lamp_mis && !(state.flag & PATH_RAY_CAMERA)) {
|
|
/* ray starting from previous non-transparent bounce */
|
|
Ray light_ray;
|
|
|
|
light_ray.P = ray.P - ray_t*ray.D;
|
|
ray_t += isect.t;
|
|
light_ray.D = ray.D;
|
|
light_ray.t = ray_t;
|
|
light_ray.time = ray.time;
|
|
light_ray.dD = ray.dD;
|
|
light_ray.dP = ray.dP;
|
|
|
|
/* intersect with lamp */
|
|
float light_t = path_rng_1D(kg, rng, sample, num_total_samples, rng_offset + PRNG_LIGHT);
|
|
float3 emission;
|
|
|
|
if(indirect_lamp_emission(kg, &light_ray, state.flag, ray_pdf, light_t, &emission))
|
|
path_radiance_accum_emission(L, throughput, emission, state.bounce);
|
|
}
|
|
#endif
|
|
|
|
if(!hit) {
|
|
#ifdef __BACKGROUND__
|
|
/* sample background shader */
|
|
float3 L_background = indirect_background(kg, &ray, state.flag, ray_pdf);
|
|
path_radiance_accum_background(L, throughput, L_background, state.bounce);
|
|
#endif
|
|
|
|
break;
|
|
}
|
|
|
|
/* setup shading */
|
|
ShaderData sd;
|
|
shader_setup_from_ray(kg, &sd, &isect, &ray);
|
|
float rbsdf = path_rng_1D(kg, rng, sample, num_total_samples, rng_offset + PRNG_BSDF);
|
|
shader_eval_surface(kg, &sd, rbsdf, state.flag, SHADER_CONTEXT_INDIRECT);
|
|
shader_merge_closures(kg, &sd);
|
|
|
|
/* 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*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) {
|
|
float3 emission = indirect_primitive_emission(kg, &sd, isect.t, state.flag, 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*num_samples);
|
|
|
|
if(probability == 0.0f) {
|
|
break;
|
|
}
|
|
else if(probability != 1.0f) {
|
|
float terminate = path_rng_1D(kg, rng, sample, num_total_samples, rng_offset + PRNG_TERMINATE);
|
|
|
|
if(terminate >= probability)
|
|
break;
|
|
|
|
throughput /= probability;
|
|
}
|
|
|
|
#ifdef __SUBSURFACE__
|
|
/* bssrdf scatter to a different location on the same object, replacing
|
|
* the closures with a diffuse BSDF */
|
|
if(sd.flag & SD_BSSRDF) {
|
|
float bssrdf_probability;
|
|
ShaderClosure *sc = subsurface_scatter_pick_closure(kg, &sd, &bssrdf_probability);
|
|
|
|
/* modify throughput for picking bssrdf or bsdf */
|
|
throughput *= bssrdf_probability;
|
|
|
|
/* do bssrdf scatter step if we picked a bssrdf closure */
|
|
if(sc) {
|
|
uint lcg_state = lcg_init(rng + rng_offset + sample*0x68bc21eb);
|
|
subsurface_scatter_step(kg, &sd, state.flag, sc, &lcg_state, false);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef __AO__
|
|
/* ambient occlusion */
|
|
if(kernel_data.integrator.use_ambient_occlusion || (sd.flag & SD_AO)) {
|
|
/* todo: solve correlation */
|
|
float2 bsdf_uv = path_rng_2D(kg, rng, sample, num_total_samples, rng_offset + PRNG_BSDF_U);
|
|
float bsdf_u = bsdf_uv.x;
|
|
float bsdf_v = bsdf_uv.y;
|
|
|
|
float ao_factor = kernel_data.background.ao_factor;
|
|
float3 ao_N;
|
|
float3 ao_bsdf = shader_bsdf_ao(kg, &sd, ao_factor, &ao_N);
|
|
float3 ao_D;
|
|
float ao_pdf;
|
|
|
|
sample_cos_hemisphere(ao_N, bsdf_u, bsdf_v, &ao_D, &ao_pdf);
|
|
|
|
if(dot(sd.Ng, ao_D) > 0.0f && ao_pdf != 0.0f) {
|
|
Ray light_ray;
|
|
float3 ao_shadow;
|
|
|
|
light_ray.P = ray_offset(sd.P, sd.Ng);
|
|
light_ray.D = ao_D;
|
|
light_ray.t = kernel_data.background.ao_distance;
|
|
#ifdef __OBJECT_MOTION__
|
|
light_ray.time = sd.time;
|
|
#endif
|
|
light_ray.dP = sd.dP;
|
|
light_ray.dD = differential3_zero();
|
|
|
|
if(!shadow_blocked(kg, &state, &light_ray, &ao_shadow))
|
|
path_radiance_accum_ao(L, throughput, ao_bsdf, ao_shadow, state.bounce);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef __EMISSION__
|
|
if(kernel_data.integrator.use_direct_light) {
|
|
/* sample illumination from lights to find path contribution */
|
|
if(sd.flag & SD_BSDF_HAS_EVAL) {
|
|
float light_t = path_rng_1D(kg, rng, sample, num_total_samples, rng_offset + PRNG_LIGHT);
|
|
#ifdef __MULTI_CLOSURE__
|
|
float light_o = 0.0f;
|
|
#else
|
|
float light_o = path_rng_1D(kg, rng, sample, num_total_samples, rng_offset + PRNG_LIGHT_F);
|
|
#endif
|
|
float2 light_uv = path_rng_2D(kg, rng, sample, num_total_samples, rng_offset + PRNG_LIGHT_U);
|
|
float light_u = light_uv.x;
|
|
float light_v = light_uv.y;
|
|
|
|
Ray light_ray;
|
|
BsdfEval L_light;
|
|
bool is_lamp;
|
|
|
|
#ifdef __OBJECT_MOTION__
|
|
light_ray.time = sd.time;
|
|
#endif
|
|
|
|
/* sample random light */
|
|
if(direct_emission(kg, &sd, -1, light_t, light_o, light_u, light_v, &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
|
|
|
|
/* no BSDF? we can stop here */
|
|
if(!(sd.flag & SD_BSDF))
|
|
break;
|
|
|
|
/* sample BSDF */
|
|
float bsdf_pdf;
|
|
BsdfEval bsdf_eval;
|
|
float3 bsdf_omega_in;
|
|
differential3 bsdf_domega_in;
|
|
float2 bsdf_uv = path_rng_2D(kg, rng, sample, num_total_samples, rng_offset + PRNG_BSDF_U);
|
|
float bsdf_u = bsdf_uv.x;
|
|
float bsdf_v = bsdf_uv.y;
|
|
int label;
|
|
|
|
label = shader_bsdf_sample(kg, &sd, bsdf_u, bsdf_v, &bsdf_eval,
|
|
&bsdf_omega_in, &bsdf_domega_in, &bsdf_pdf);
|
|
|
|
if(bsdf_pdf == 0.0f || bsdf_eval_is_zero(&bsdf_eval))
|
|
break;
|
|
|
|
/* modify throughput */
|
|
path_radiance_bsdf_bounce(L, &throughput, &bsdf_eval, bsdf_pdf, state.bounce, label);
|
|
|
|
/* set labels */
|
|
if(!(label & LABEL_TRANSPARENT)) {
|
|
ray_pdf = bsdf_pdf;
|
|
#ifdef __LAMP_MIS__
|
|
ray_t = 0.0f;
|
|
#endif
|
|
min_ray_pdf = fminf(bsdf_pdf, min_ray_pdf);
|
|
}
|
|
|
|
/* update path state */
|
|
path_state_next(kg, &state, label);
|
|
|
|
/* setup ray */
|
|
ray.P = ray_offset(sd.P, (label & LABEL_TRANSMIT)? -sd.Ng: sd.Ng);
|
|
ray.D = bsdf_omega_in;
|
|
ray.t = FLT_MAX;
|
|
#ifdef __RAY_DIFFERENTIALS__
|
|
ray.dP = sd.dP;
|
|
ray.dD = bsdf_domega_in;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
__device_noinline void kernel_path_non_progressive_lighting(KernelGlobals *kg, RNG rng, int sample,
|
|
ShaderData *sd, float3 throughput, float num_samples_adjust,
|
|
float min_ray_pdf, float ray_pdf, PathState state,
|
|
int rng_offset, PathRadiance *L, __global float *buffer)
|
|
{
|
|
int aa_samples = kernel_data.integrator.aa_samples;
|
|
|
|
#ifdef __AO__
|
|
/* ambient occlusion */
|
|
if(kernel_data.integrator.use_ambient_occlusion || (sd->flag & SD_AO)) {
|
|
int num_samples = ceil_to_int(kernel_data.integrator.ao_samples*num_samples_adjust);
|
|
float num_samples_inv = num_samples_adjust/num_samples;
|
|
float ao_factor = kernel_data.background.ao_factor;
|
|
float3 ao_N;
|
|
float3 ao_bsdf = shader_bsdf_ao(kg, sd, ao_factor, &ao_N);
|
|
|
|
for(int j = 0; j < num_samples; j++) {
|
|
/* todo: solve correlation */
|
|
float2 bsdf_uv = path_rng_2D(kg, rng, sample*num_samples + j, aa_samples*num_samples, rng_offset + PRNG_BSDF_U);
|
|
float bsdf_u = bsdf_uv.x;
|
|
float bsdf_v = bsdf_uv.y;
|
|
|
|
float3 ao_D;
|
|
float ao_pdf;
|
|
|
|
sample_cos_hemisphere(ao_N, bsdf_u, bsdf_v, &ao_D, &ao_pdf);
|
|
|
|
if(dot(sd->Ng, ao_D) > 0.0f && ao_pdf != 0.0f) {
|
|
Ray light_ray;
|
|
float3 ao_shadow;
|
|
|
|
light_ray.P = ray_offset(sd->P, sd->Ng);
|
|
light_ray.D = ao_D;
|
|
light_ray.t = kernel_data.background.ao_distance;
|
|
#ifdef __OBJECT_MOTION__
|
|
light_ray.time = sd->time;
|
|
#endif
|
|
light_ray.dP = sd->dP;
|
|
light_ray.dD = differential3_zero();
|
|
|
|
if(!shadow_blocked(kg, &state, &light_ray, &ao_shadow))
|
|
path_radiance_accum_ao(L, throughput*num_samples_inv, ao_bsdf, ao_shadow, state.bounce);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
|
|
#ifdef __EMISSION__
|
|
/* sample illumination from lights to find path contribution */
|
|
if(sd->flag & SD_BSDF_HAS_EVAL) {
|
|
Ray light_ray;
|
|
BsdfEval L_light;
|
|
bool is_lamp;
|
|
|
|
#ifdef __OBJECT_MOTION__
|
|
light_ray.time = sd->time;
|
|
#endif
|
|
|
|
/* lamp sampling */
|
|
for(int i = 0; i < kernel_data.integrator.num_all_lights; i++) {
|
|
int num_samples = ceil_to_int(num_samples_adjust*light_select_num_samples(kg, i));
|
|
float num_samples_inv = num_samples_adjust/(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++) {
|
|
float2 light_uv = path_rng_2D(kg, lamp_rng, sample*num_samples + j, aa_samples*num_samples, rng_offset + PRNG_LIGHT_U);
|
|
float light_u = light_uv.x;
|
|
float light_v = light_uv.y;
|
|
|
|
if(direct_emission(kg, sd, i, 0.0f, 0.0f, light_u, light_v, &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*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 = ceil_to_int(num_samples_adjust*kernel_data.integrator.mesh_light_samples);
|
|
float num_samples_inv = num_samples_adjust/num_samples;
|
|
|
|
if(kernel_data.integrator.num_all_lights)
|
|
num_samples_inv *= 0.5f;
|
|
|
|
for(int j = 0; j < num_samples; j++) {
|
|
float light_t = path_rng_1D(kg, rng, sample*num_samples + j, aa_samples*num_samples, rng_offset + PRNG_LIGHT);
|
|
float2 light_uv = path_rng_2D(kg, rng, sample*num_samples + j, aa_samples*num_samples, rng_offset + PRNG_LIGHT_U);
|
|
float light_u = light_uv.x;
|
|
float light_v = light_uv.y;
|
|
|
|
/* only sample triangle lights */
|
|
if(kernel_data.integrator.num_all_lights)
|
|
light_t = 0.5f*light_t;
|
|
|
|
if(direct_emission(kg, sd, -1, light_t, 0.0f, light_u, light_v, &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*num_samples_inv, &L_light, shadow, num_samples_inv, state.bounce, is_lamp);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
for(int i = 0; i< sd->num_closure; i++) {
|
|
const ShaderClosure *sc = &sd->closure[i];
|
|
|
|
if(!CLOSURE_IS_BSDF(sc->type))
|
|
continue;
|
|
/* transparency is not handled here, but in outer loop */
|
|
if(sc->type == CLOSURE_BSDF_TRANSPARENT_ID)
|
|
continue;
|
|
|
|
int num_samples;
|
|
|
|
if(CLOSURE_IS_BSDF_DIFFUSE(sc->type))
|
|
num_samples = kernel_data.integrator.diffuse_samples;
|
|
else if(CLOSURE_IS_BSDF_GLOSSY(sc->type))
|
|
num_samples = kernel_data.integrator.glossy_samples;
|
|
else
|
|
num_samples = kernel_data.integrator.transmission_samples;
|
|
|
|
num_samples = ceil_to_int(num_samples_adjust*num_samples);
|
|
|
|
float num_samples_inv = num_samples_adjust/num_samples;
|
|
RNG bsdf_rng = cmj_hash(rng, i);
|
|
|
|
for(int j = 0; j < num_samples; j++) {
|
|
/* sample BSDF */
|
|
float bsdf_pdf;
|
|
BsdfEval bsdf_eval;
|
|
float3 bsdf_omega_in;
|
|
differential3 bsdf_domega_in;
|
|
float2 bsdf_uv = path_rng_2D(kg, bsdf_rng, sample*num_samples + j, aa_samples*num_samples, rng_offset + PRNG_BSDF_U);
|
|
float bsdf_u = bsdf_uv.x;
|
|
float bsdf_v = bsdf_uv.y;
|
|
int label;
|
|
|
|
label = shader_bsdf_sample_closure(kg, sd, sc, bsdf_u, bsdf_v, &bsdf_eval,
|
|
&bsdf_omega_in, &bsdf_domega_in, &bsdf_pdf);
|
|
|
|
if(bsdf_pdf == 0.0f || bsdf_eval_is_zero(&bsdf_eval))
|
|
continue;
|
|
|
|
/* modify throughput */
|
|
float3 tp = throughput;
|
|
path_radiance_bsdf_bounce(L, &tp, &bsdf_eval, bsdf_pdf, state.bounce, label);
|
|
|
|
/* set labels */
|
|
float min_ray_pdf = FLT_MAX;
|
|
|
|
if(!(label & LABEL_TRANSPARENT))
|
|
min_ray_pdf = fminf(bsdf_pdf, min_ray_pdf);
|
|
|
|
/* modify path state */
|
|
PathState ps = state;
|
|
path_state_next(kg, &ps, label);
|
|
|
|
/* setup ray */
|
|
Ray bsdf_ray;
|
|
|
|
bsdf_ray.P = ray_offset(sd->P, (label & LABEL_TRANSMIT)? -sd->Ng: sd->Ng);
|
|
bsdf_ray.D = bsdf_omega_in;
|
|
bsdf_ray.t = FLT_MAX;
|
|
#ifdef __RAY_DIFFERENTIALS__
|
|
bsdf_ray.dP = sd->dP;
|
|
bsdf_ray.dD = bsdf_domega_in;
|
|
#endif
|
|
#ifdef __OBJECT_MOTION__
|
|
bsdf_ray.time = sd->time;
|
|
#endif
|
|
|
|
kernel_path_indirect(kg, rng, sample*num_samples + j, bsdf_ray, buffer,
|
|
tp*num_samples_inv, num_samples, aa_samples*num_samples,
|
|
min_ray_pdf, bsdf_pdf, ps, rng_offset+PRNG_BOUNCE_NUM, L);
|
|
|
|
/* for render passes, sum and reset indirect light pass variables
|
|
* for the next samples */
|
|
path_radiance_sum_indirect(L);
|
|
path_radiance_reset_indirect(L);
|
|
}
|
|
}
|
|
}
|
|
|
|
__device float4 kernel_path_non_progressive(KernelGlobals *kg, RNG rng, int sample, Ray ray, __global float *buffer)
|
|
{
|
|
/* initialize */
|
|
PathRadiance L;
|
|
float3 throughput = make_float3(1.0f, 1.0f, 1.0f);
|
|
float L_transparent = 0.0f;
|
|
|
|
path_radiance_init(&L, kernel_data.film.use_light_pass);
|
|
|
|
float ray_pdf = 0.0f;
|
|
PathState state;
|
|
int rng_offset = PRNG_BASE_NUM;
|
|
int aa_samples = kernel_data.integrator.aa_samples;
|
|
|
|
path_state_init(&state);
|
|
|
|
for(;; rng_offset += PRNG_BOUNCE_NUM) {
|
|
/* intersect scene */
|
|
Intersection isect;
|
|
uint visibility = path_state_ray_visibility(kg, &state);
|
|
|
|
#ifdef __HAIR__
|
|
float difl = 0.0f, extmax = 0.0f;
|
|
uint lcg_state = 0;
|
|
|
|
if(kernel_data.bvh.have_curves) {
|
|
if((kernel_data.cam.resolution == 1) && (state.flag & PATH_RAY_CAMERA)) {
|
|
float3 pixdiff = ray.dD.dx + ray.dD.dy;
|
|
/*pixdiff = pixdiff - dot(pixdiff, ray.D)*ray.D;*/
|
|
difl = kernel_data.curve_kernel_data.minimum_width * len(pixdiff) * 0.5f;
|
|
}
|
|
|
|
extmax = kernel_data.curve_kernel_data.maximum_width;
|
|
lcg_state = lcg_init(rng + rng_offset + sample*0x51633e2d);
|
|
}
|
|
|
|
if(!scene_intersect(kg, &ray, visibility, &isect, &lcg_state, difl, extmax)) {
|
|
#else
|
|
if(!scene_intersect(kg, &ray, visibility, &isect)) {
|
|
#endif
|
|
/* eval background shader if nothing hit */
|
|
if(kernel_data.background.transparent) {
|
|
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, &ray, state.flag, ray_pdf);
|
|
path_radiance_accum_background(&L, throughput, L_background, state.bounce);
|
|
#endif
|
|
|
|
break;
|
|
}
|
|
|
|
/* setup shading */
|
|
ShaderData sd;
|
|
shader_setup_from_ray(kg, &sd, &isect, &ray);
|
|
shader_eval_surface(kg, &sd, 0.0f, state.flag, SHADER_CONTEXT_MAIN);
|
|
shader_merge_closures(kg, &sd);
|
|
|
|
/* holdout */
|
|
#ifdef __HOLDOUT__
|
|
if((sd.flag & (SD_HOLDOUT|SD_HOLDOUT_MASK))) {
|
|
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.flag, throughput);
|
|
|
|
#ifdef __EMISSION__
|
|
/* emission */
|
|
if(sd.flag & SD_EMISSION) {
|
|
float3 emission = indirect_primitive_emission(kg, &sd, isect.t, state.flag, ray_pdf);
|
|
path_radiance_accum_emission(&L, throughput, emission, state.bounce);
|
|
}
|
|
#endif
|
|
|
|
/* transparency termination */
|
|
if(state.flag & PATH_RAY_TRANSPARENT) {
|
|
/* 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_rng_1D(kg, rng, sample, aa_samples, rng_offset + PRNG_TERMINATE);
|
|
|
|
if(terminate >= probability)
|
|
break;
|
|
|
|
throughput /= probability;
|
|
}
|
|
}
|
|
|
|
#ifdef __SUBSURFACE__
|
|
/* bssrdf scatter to a different location on the same object */
|
|
if(sd.flag & SD_BSSRDF) {
|
|
for(int i = 0; i< sd.num_closure; i++) {
|
|
ShaderClosure *sc = &sd.closure[i];
|
|
|
|
if(!CLOSURE_IS_BSSRDF(sc->type))
|
|
continue;
|
|
|
|
/* set up random number generator */
|
|
uint lcg_state = lcg_init(rng + rng_offset + sample*0x68bc21eb);
|
|
int num_samples = kernel_data.integrator.subsurface_samples;
|
|
float num_samples_inv = 1.0f/num_samples;
|
|
|
|
/* do subsurface scatter step with copy of shader data, this will
|
|
* replace the BSSRDF with a diffuse BSDF closure */
|
|
for(int j = 0; j < num_samples; j++) {
|
|
ShaderData bssrdf_sd = sd;
|
|
subsurface_scatter_step(kg, &bssrdf_sd, state.flag, sc, &lcg_state, true);
|
|
|
|
/* compute lighting with the BSDF closure */
|
|
kernel_path_non_progressive_lighting(kg, rng, sample*num_samples + j,
|
|
&bssrdf_sd, throughput, num_samples_inv,
|
|
ray_pdf, ray_pdf, state, rng_offset, &L, buffer);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* lighting */
|
|
kernel_path_non_progressive_lighting(kg, rng, sample, &sd, throughput,
|
|
1.0f, ray_pdf, ray_pdf, state, rng_offset, &L, buffer);
|
|
|
|
/* continue in case of transparency */
|
|
throughput *= shader_bsdf_transparency(kg, &sd);
|
|
|
|
if(is_zero(throughput))
|
|
break;
|
|
|
|
path_state_next(kg, &state, LABEL_TRANSPARENT);
|
|
ray.P = ray_offset(sd.P, -sd.Ng);
|
|
ray.t -= sd.ray_length; /* clipping works through transparent */
|
|
}
|
|
|
|
float3 L_sum = path_radiance_sum(kg, &L);
|
|
|
|
#ifdef __CLAMP_SAMPLE__
|
|
path_radiance_clamp(&L, &L_sum, kernel_data.integrator.sample_clamp);
|
|
#endif
|
|
|
|
kernel_write_light_passes(kg, buffer, &L, sample);
|
|
|
|
return make_float4(L_sum.x, L_sum.y, L_sum.z, 1.0f - L_transparent);
|
|
}
|
|
|
|
#endif
|
|
|
|
__device void kernel_path_trace(KernelGlobals *kg,
|
|
__global float *buffer, __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 */
|
|
RNG rng;
|
|
|
|
float filter_u;
|
|
float filter_v;
|
|
int num_samples = kernel_data.integrator.aa_samples;
|
|
|
|
path_rng_init(kg, rng_state, sample, num_samples, &rng, x, y, &filter_u, &filter_v);
|
|
|
|
/* sample camera ray */
|
|
Ray ray;
|
|
|
|
float lens_u = 0.0f, lens_v = 0.0f;
|
|
|
|
if(kernel_data.cam.aperturesize > 0.0f) {
|
|
float2 lens_uv = path_rng_2D(kg, rng, sample, num_samples, PRNG_LENS_U);
|
|
lens_u = lens_uv.x;
|
|
lens_v = lens_uv.y;
|
|
}
|
|
|
|
float time = 0.0f;
|
|
|
|
#ifdef __CAMERA_MOTION__
|
|
if(kernel_data.cam.shuttertime != -1.0f)
|
|
time = path_rng_1D(kg, rng, sample, num_samples, PRNG_TIME);
|
|
#endif
|
|
|
|
camera_sample(kg, x, y, filter_u, filter_v, lens_u, lens_v, time, &ray);
|
|
|
|
/* integrate */
|
|
float4 L;
|
|
|
|
if (ray.t != 0.0f) {
|
|
#ifdef __NON_PROGRESSIVE__
|
|
if(kernel_data.integrator.progressive)
|
|
#endif
|
|
L = kernel_path_progressive(kg, rng, sample, ray, buffer);
|
|
#ifdef __NON_PROGRESSIVE__
|
|
else
|
|
L = kernel_path_non_progressive(kg, rng, sample, ray, buffer);
|
|
#endif
|
|
}
|
|
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
|
|
|