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test/intern/cycles/kernel/integrator/shade_background.h

213 lines
7.7 KiB
C

/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
*
* SPDX-License-Identifier: Apache-2.0 */
#pragma once
#include "kernel/film/data_passes.h"
#include "kernel/film/light_passes.h"
#include "kernel/integrator/guiding.h"
#include "kernel/integrator/surface_shader.h"
#include "kernel/light/light.h"
#include "kernel/light/sample.h"
CCL_NAMESPACE_BEGIN
ccl_device Spectrum integrator_eval_background_shader(KernelGlobals kg,
IntegratorState state,
ccl_global float *ccl_restrict render_buffer)
{
const int shader = kernel_data.background.surface_shader;
const uint32_t path_flag = INTEGRATOR_STATE(state, path, flag);
/* Use visibility flag to skip lights. */
if (!is_light_shader_visible_to_path(shader, path_flag)) {
return zero_spectrum();
}
/* Use fast constant background color if available. */
Spectrum L = zero_spectrum();
if (surface_shader_constant_emission(kg, shader, &L)) {
return L;
}
/* Evaluate background shader. */
/* TODO: does aliasing like this break automatic SoA in CUDA?
* Should we instead store closures separate from ShaderData? */
ShaderDataTinyStorage emission_sd_storage;
ccl_private ShaderData *emission_sd = AS_SHADER_DATA(&emission_sd_storage);
PROFILING_INIT_FOR_SHADER(kg, PROFILING_SHADE_LIGHT_SETUP);
shader_setup_from_background(kg,
emission_sd,
INTEGRATOR_STATE(state, ray, P),
INTEGRATOR_STATE(state, ray, D),
INTEGRATOR_STATE(state, ray, time));
PROFILING_SHADER(emission_sd->object, emission_sd->shader);
PROFILING_EVENT(PROFILING_SHADE_LIGHT_EVAL);
surface_shader_eval<KERNEL_FEATURE_NODE_MASK_SURFACE_BACKGROUND>(
kg, state, emission_sd, render_buffer, path_flag | PATH_RAY_EMISSION);
return surface_shader_background(emission_sd);
}
ccl_device_inline void integrate_background(KernelGlobals kg,
IntegratorState state,
ccl_global float *ccl_restrict render_buffer)
{
/* Accumulate transparency for transparent background. We can skip background
* shader evaluation unless a background pass is used. */
bool eval_background = true;
float transparent = 0.0f;
int path_flag = INTEGRATOR_STATE(state, path, flag);
const bool is_transparent_background_ray = kernel_data.background.transparent &&
(path_flag & PATH_RAY_TRANSPARENT_BACKGROUND);
if (is_transparent_background_ray) {
transparent = average(INTEGRATOR_STATE(state, path, throughput));
#ifdef __PASSES__
eval_background = (kernel_data.film.light_pass_flag & PASSMASK(BACKGROUND));
#else
eval_background = false;
#endif
}
#ifdef __MNEE__
if (INTEGRATOR_STATE(state, path, mnee) & PATH_MNEE_CULL_LIGHT_CONNECTION) {
if (kernel_data.background.use_mis) {
for (int lamp = 0; lamp < kernel_data.integrator.num_lights; lamp++) {
/* This path should have been resolved with mnee, it will
* generate a firefly for small lights since it is improbable. */
const ccl_global KernelLight *klight = &kernel_data_fetch(lights, lamp);
if (klight->type == LIGHT_BACKGROUND && klight->use_caustics) {
eval_background = false;
break;
}
}
}
}
#endif /* __MNEE__ */
/* Evaluate background shader. */
Spectrum L = zero_spectrum();
if (eval_background) {
L = integrator_eval_background_shader(kg, state, render_buffer);
/* When using the ao bounces approximation, adjust background
* shader intensity with ao factor. */
if (path_state_ao_bounce(kg, state)) {
L *= kernel_data.integrator.ao_bounces_factor;
}
/* Background MIS weights. */
float mis_weight = 1.0f;
/* Check if background light exists or if we should skip PDF. */
if (!(INTEGRATOR_STATE(state, path, flag) & PATH_RAY_MIS_SKIP) &&
kernel_data.background.use_mis) {
mis_weight = light_sample_mis_weight_forward_background(kg, state, path_flag);
}
guiding_record_background(kg, state, L, mis_weight);
L *= mis_weight;
}
/* Write to render buffer. */
film_write_background(kg, state, L, transparent, is_transparent_background_ray, render_buffer);
film_write_data_passes_background(kg, state, render_buffer);
}
ccl_device_inline void integrate_distant_lights(KernelGlobals kg,
IntegratorState state,
ccl_global float *ccl_restrict render_buffer)
{
const float3 ray_D = INTEGRATOR_STATE(state, ray, D);
const float ray_time = INTEGRATOR_STATE(state, ray, time);
LightSample ls ccl_optional_struct_init;
for (int lamp = 0; lamp < kernel_data.integrator.num_lights; lamp++) {
if (distant_light_sample_from_intersection(kg, ray_D, lamp, &ls)) {
/* Use visibility flag to skip lights. */
#ifdef __PASSES__
const uint32_t path_flag = INTEGRATOR_STATE(state, path, flag);
if (!is_light_shader_visible_to_path(ls.shader, path_flag)) {
continue;
}
#endif
#ifdef __LIGHT_LINKING__
if (!light_link_light_match(kg, light_link_receiver_forward(kg, state), lamp) &&
!(path_flag & PATH_RAY_CAMERA))
{
continue;
}
#endif
#ifdef __SHADOW_LINKING__
if (kernel_data_fetch(lights, lamp).shadow_set_membership != LIGHT_LINK_MASK_ALL) {
continue;
}
#endif
#ifdef __MNEE__
if (INTEGRATOR_STATE(state, path, mnee) & PATH_MNEE_CULL_LIGHT_CONNECTION) {
/* This path should have been resolved with mnee, it will
* generate a firefly for small lights since it is improbable. */
const ccl_global KernelLight *klight = &kernel_data_fetch(lights, lamp);
if (klight->use_caustics)
continue;
}
#endif /* __MNEE__ */
/* Evaluate light shader. */
/* TODO: does aliasing like this break automatic SoA in CUDA? */
ShaderDataTinyStorage emission_sd_storage;
ccl_private ShaderData *emission_sd = AS_SHADER_DATA(&emission_sd_storage);
Spectrum light_eval = light_sample_shader_eval(kg, state, emission_sd, &ls, ray_time);
if (is_zero(light_eval)) {
continue;
}
/* MIS weighting. */
float mis_weight = 1.0f;
if (!(path_flag & PATH_RAY_MIS_SKIP)) {
mis_weight = light_sample_mis_weight_forward_distant(kg, state, path_flag, &ls);
}
/* Write to render buffer. */
guiding_record_background(kg, state, light_eval, mis_weight);
film_write_surface_emission(kg, state, light_eval, mis_weight, render_buffer, ls.group);
}
}
}
ccl_device void integrator_shade_background(KernelGlobals kg,
IntegratorState state,
ccl_global float *ccl_restrict render_buffer)
{
PROFILING_INIT(kg, PROFILING_SHADE_LIGHT_SETUP);
/* TODO: unify these in a single loop to only have a single shader evaluation call. */
integrate_distant_lights(kg, state, render_buffer);
integrate_background(kg, state, render_buffer);
#ifdef __SHADOW_CATCHER__
if (INTEGRATOR_STATE(state, path, flag) & PATH_RAY_SHADOW_CATCHER_BACKGROUND) {
/* Special case for shadow catcher where we want to fill the background pass
* behind the shadow catcher but also continue tracing the path. */
INTEGRATOR_STATE_WRITE(state, path, flag) &= ~PATH_RAY_SHADOW_CATCHER_BACKGROUND;
integrator_intersect_next_kernel_after_shadow_catcher_background<
DEVICE_KERNEL_INTEGRATOR_SHADE_BACKGROUND>(kg, state);
return;
}
#endif
integrator_path_terminate(kg, state, DEVICE_KERNEL_INTEGRATOR_SHADE_BACKGROUND);
}
CCL_NAMESPACE_END