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blender-archive/intern/cycles/scene/light.cpp
Brecht Van Lommel b288c4004e Cleanup: fix various Cycles compilar warnings
Mainly for the build configuration of the Hydra render delegate and
standalone repo.
2023-04-05 19:48:19 +02:00

1253 lines
41 KiB
C++

/* SPDX-License-Identifier: Apache-2.0
* Copyright 2011-2022 Blender Foundation */
#include "device/device.h"
#include "scene/background.h"
#include "scene/film.h"
#include "scene/integrator.h"
#include "scene/light.h"
#include "scene/light_tree.h"
#include "scene/mesh.h"
#include "scene/object.h"
#include "scene/scene.h"
#include "scene/shader.h"
#include "scene/shader_graph.h"
#include "scene/shader_nodes.h"
#include "scene/stats.h"
#include "integrator/shader_eval.h"
#include "util/foreach.h"
#include "util/hash.h"
#include "util/log.h"
#include "util/path.h"
#include "util/progress.h"
#include "util/task.h"
CCL_NAMESPACE_BEGIN
static void shade_background_pixels(Device *device,
DeviceScene *dscene,
int width,
int height,
vector<float3> &pixels,
Progress &progress)
{
/* Needs to be up to data for attribute access. */
device->const_copy_to("data", &dscene->data, sizeof(dscene->data));
const int size = width * height;
const int num_channels = 3;
pixels.resize(size);
/* Evaluate shader on device. */
ShaderEval shader_eval(device, progress);
shader_eval.eval(
SHADER_EVAL_BACKGROUND,
size,
num_channels,
[&](device_vector<KernelShaderEvalInput> &d_input) {
/* Fill coordinates for shading. */
KernelShaderEvalInput *d_input_data = d_input.data();
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
float u = (x + 0.5f) / width;
float v = (y + 0.5f) / height;
KernelShaderEvalInput in;
in.object = OBJECT_NONE;
in.prim = PRIM_NONE;
in.u = u;
in.v = v;
d_input_data[x + y * width] = in;
}
}
return size;
},
[&](device_vector<float> &d_output) {
/* Copy output to pixel buffer. */
float *d_output_data = d_output.data();
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
pixels[y * width + x].x = d_output_data[(y * width + x) * num_channels + 0];
pixels[y * width + x].y = d_output_data[(y * width + x) * num_channels + 1];
pixels[y * width + x].z = d_output_data[(y * width + x) * num_channels + 2];
}
}
});
}
/* Light */
NODE_DEFINE(Light)
{
NodeType *type = NodeType::add("light", create);
static NodeEnum type_enum;
type_enum.insert("point", LIGHT_POINT);
type_enum.insert("distant", LIGHT_DISTANT);
type_enum.insert("background", LIGHT_BACKGROUND);
type_enum.insert("area", LIGHT_AREA);
type_enum.insert("spot", LIGHT_SPOT);
SOCKET_ENUM(light_type, "Type", type_enum, LIGHT_POINT);
SOCKET_COLOR(strength, "Strength", one_float3());
SOCKET_POINT(co, "Co", zero_float3());
SOCKET_VECTOR(dir, "Dir", zero_float3());
SOCKET_FLOAT(size, "Size", 0.0f);
SOCKET_FLOAT(angle, "Angle", 0.0f);
SOCKET_VECTOR(axisu, "Axis U", zero_float3());
SOCKET_FLOAT(sizeu, "Size U", 1.0f);
SOCKET_VECTOR(axisv, "Axis V", zero_float3());
SOCKET_FLOAT(sizev, "Size V", 1.0f);
SOCKET_BOOLEAN(ellipse, "Ellipse", false);
SOCKET_FLOAT(spread, "Spread", M_PI_F);
SOCKET_INT(map_resolution, "Map Resolution", 0);
SOCKET_FLOAT(average_radiance, "Average Radiance", 0.0f);
SOCKET_FLOAT(spot_angle, "Spot Angle", M_PI_4_F);
SOCKET_FLOAT(spot_smooth, "Spot Smooth", 0.0f);
SOCKET_TRANSFORM(tfm, "Transform", transform_identity());
SOCKET_BOOLEAN(cast_shadow, "Cast Shadow", true);
SOCKET_BOOLEAN(use_mis, "Use Mis", false);
SOCKET_BOOLEAN(use_camera, "Use Camera", true);
SOCKET_BOOLEAN(use_diffuse, "Use Diffuse", true);
SOCKET_BOOLEAN(use_glossy, "Use Glossy", true);
SOCKET_BOOLEAN(use_transmission, "Use Transmission", true);
SOCKET_BOOLEAN(use_scatter, "Use Scatter", true);
SOCKET_BOOLEAN(use_caustics, "Shadow Caustics", false);
SOCKET_INT(max_bounces, "Max Bounces", 1024);
SOCKET_UINT(random_id, "Random ID", 0);
SOCKET_BOOLEAN(is_shadow_catcher, "Shadow Catcher", true);
SOCKET_BOOLEAN(is_portal, "Is Portal", false);
SOCKET_BOOLEAN(is_enabled, "Is Enabled", true);
SOCKET_NODE(shader, "Shader", Shader::get_node_type());
SOCKET_STRING(lightgroup, "Light Group", ustring());
SOCKET_BOOLEAN(normalize, "Normalize", true);
return type;
}
Light::Light() : Node(get_node_type())
{
dereference_all_used_nodes();
}
void Light::tag_update(Scene *scene)
{
if (is_modified()) {
scene->light_manager->tag_update(scene, LightManager::LIGHT_MODIFIED);
}
}
bool Light::has_contribution(Scene *scene)
{
if (strength == zero_float3()) {
return false;
}
if (is_portal) {
return false;
}
if (light_type == LIGHT_BACKGROUND) {
return true;
}
const Shader *effective_shader = (shader) ? shader : scene->default_light;
return !is_zero(effective_shader->emission_estimate);
}
/* Light Manager */
LightManager::LightManager()
{
update_flags = UPDATE_ALL;
need_update_background = true;
last_background_enabled = false;
last_background_resolution = 0;
}
LightManager::~LightManager()
{
foreach (IESSlot *slot, ies_slots) {
delete slot;
}
}
bool LightManager::has_background_light(Scene *scene)
{
foreach (Light *light, scene->lights) {
if (light->light_type == LIGHT_BACKGROUND && light->is_enabled) {
return true;
}
}
return false;
}
void LightManager::test_enabled_lights(Scene *scene)
{
/* Make all lights enabled by default, and perform some preliminary checks
* needed for finer-tuning of settings (for example, check whether we've
* got portals or not).
*/
bool has_portal = false, has_background = false;
foreach (Light *light, scene->lights) {
light->is_enabled = light->has_contribution(scene);
has_portal |= light->is_portal;
has_background |= light->light_type == LIGHT_BACKGROUND;
}
bool background_enabled = false;
int background_resolution = 0;
if (has_background) {
/* Ignore background light if:
* - If unsupported on a device
* - If we don't need it (no HDRs etc.)
*/
Shader *shader = scene->background->get_shader(scene);
const bool disable_mis = !(has_portal || shader->has_surface_spatial_varying);
if (disable_mis) {
VLOG_INFO << "Background MIS has been disabled.\n";
}
foreach (Light *light, scene->lights) {
if (light->light_type == LIGHT_BACKGROUND) {
light->is_enabled = !disable_mis;
background_enabled = !disable_mis;
background_resolution = light->map_resolution;
}
}
}
if (last_background_enabled != background_enabled ||
last_background_resolution != background_resolution) {
last_background_enabled = background_enabled;
last_background_resolution = background_resolution;
need_update_background = true;
}
}
void LightManager::device_update_distribution(Device *,
DeviceScene *dscene,
Scene *scene,
Progress &progress)
{
KernelIntegrator *kintegrator = &dscene->data.integrator;
/* Update CDF over lights. */
progress.set_status("Updating Lights", "Computing distribution");
/* Counts emissive triangles in the scene. */
size_t num_triangles = 0;
foreach (Object *object, scene->objects) {
if (progress.get_cancel())
return;
if (!object->usable_as_light()) {
continue;
}
/* Count emissive triangles. */
Mesh *mesh = static_cast<Mesh *>(object->get_geometry());
int mesh_num_triangles = static_cast<int>(mesh->num_triangles());
for (int i = 0; i < mesh_num_triangles; i++) {
int shader_index = mesh->get_shader()[i];
Shader *shader = (shader_index < mesh->get_used_shaders().size()) ?
static_cast<Shader *>(mesh->get_used_shaders()[shader_index]) :
scene->default_surface;
if (shader->emission_sampling != EMISSION_SAMPLING_NONE) {
num_triangles++;
}
}
}
const size_t num_lights = kintegrator->num_lights;
const size_t num_distribution = num_triangles + num_lights;
/* Distribution size. */
kintegrator->num_distribution = num_distribution;
VLOG_INFO << "Total " << num_distribution << " of light distribution primitives.";
if (kintegrator->use_light_tree) {
dscene->light_distribution.free();
return;
}
/* Emission area. */
KernelLightDistribution *distribution = dscene->light_distribution.alloc(num_distribution + 1);
float totarea = 0.0f;
/* Triangles. */
size_t offset = 0;
int j = 0;
foreach (Object *object, scene->objects) {
if (progress.get_cancel())
return;
if (!object->usable_as_light()) {
j++;
continue;
}
/* Sum area. */
Mesh *mesh = static_cast<Mesh *>(object->get_geometry());
bool transform_applied = mesh->transform_applied;
Transform tfm = object->get_tfm();
int object_id = j;
int shader_flag = 0;
if (!(object->get_visibility() & PATH_RAY_CAMERA)) {
shader_flag |= SHADER_EXCLUDE_CAMERA;
}
if (!(object->get_visibility() & PATH_RAY_DIFFUSE)) {
shader_flag |= SHADER_EXCLUDE_DIFFUSE;
}
if (!(object->get_visibility() & PATH_RAY_GLOSSY)) {
shader_flag |= SHADER_EXCLUDE_GLOSSY;
}
if (!(object->get_visibility() & PATH_RAY_TRANSMIT)) {
shader_flag |= SHADER_EXCLUDE_TRANSMIT;
}
if (!(object->get_visibility() & PATH_RAY_VOLUME_SCATTER)) {
shader_flag |= SHADER_EXCLUDE_SCATTER;
}
if (!(object->get_is_shadow_catcher())) {
shader_flag |= SHADER_EXCLUDE_SHADOW_CATCHER;
}
size_t mesh_num_triangles = mesh->num_triangles();
for (size_t i = 0; i < mesh_num_triangles; i++) {
int shader_index = mesh->get_shader()[i];
Shader *shader = (shader_index < mesh->get_used_shaders().size()) ?
static_cast<Shader *>(mesh->get_used_shaders()[shader_index]) :
scene->default_surface;
if (shader->emission_sampling != EMISSION_SAMPLING_NONE) {
distribution[offset].totarea = totarea;
distribution[offset].prim = i + mesh->prim_offset;
distribution[offset].mesh_light.shader_flag = shader_flag;
distribution[offset].mesh_light.object_id = object_id;
offset++;
Mesh::Triangle t = mesh->get_triangle(i);
if (!t.valid(&mesh->get_verts()[0])) {
continue;
}
float3 p1 = mesh->get_verts()[t.v[0]];
float3 p2 = mesh->get_verts()[t.v[1]];
float3 p3 = mesh->get_verts()[t.v[2]];
if (!transform_applied) {
p1 = transform_point(&tfm, p1);
p2 = transform_point(&tfm, p2);
p3 = transform_point(&tfm, p3);
}
totarea += triangle_area(p1, p2, p3);
}
}
j++;
}
const float trianglearea = totarea;
/* Lights. */
int light_index = 0;
if (num_lights > 0) {
float lightarea = (totarea > 0.0f) ? totarea / num_lights : 1.0f;
foreach (Light *light, scene->lights) {
if (!light->is_enabled)
continue;
distribution[offset].totarea = totarea;
distribution[offset].prim = ~light_index;
distribution[offset].mesh_light.object_id = OBJECT_NONE;
distribution[offset].mesh_light.shader_flag = 0;
totarea += lightarea;
light_index++;
offset++;
}
}
/* normalize cumulative distribution functions */
distribution[num_distribution].totarea = totarea;
distribution[num_distribution].prim = 0;
distribution[num_distribution].mesh_light.object_id = OBJECT_NONE;
distribution[num_distribution].mesh_light.shader_flag = 0;
if (totarea > 0.0f) {
for (size_t i = 0; i < num_distribution; i++)
distribution[i].totarea /= totarea;
distribution[num_distribution].totarea = 1.0f;
}
if (progress.get_cancel())
return;
/* Update integrator state. */
kintegrator->use_direct_light = (totarea > 0.0f);
/* Precompute pdfs for distribution sampling.
* Sample one, with 0.5 probability of light or triangle. */
kintegrator->distribution_pdf_triangles = 0.0f;
kintegrator->distribution_pdf_lights = 0.0f;
if (trianglearea > 0.0f) {
kintegrator->distribution_pdf_triangles = 1.0f / trianglearea;
if (num_lights) {
kintegrator->distribution_pdf_triangles *= 0.5f;
}
}
if (num_lights) {
kintegrator->distribution_pdf_lights = 1.0f / num_lights;
if (trianglearea > 0.0f) {
kintegrator->distribution_pdf_lights *= 0.5f;
}
}
/* Copy distribution to device. */
dscene->light_distribution.copy_to_device();
}
void LightManager::device_update_tree(Device *,
DeviceScene *dscene,
Scene *scene,
Progress &progress)
{
KernelIntegrator *kintegrator = &dscene->data.integrator;
if (!kintegrator->use_light_tree) {
return;
}
/* Update light tree. */
progress.set_status("Updating Lights", "Computing tree");
/* TODO: For now, we'll start with a smaller number of max lights in a node.
* More benchmarking is needed to determine what number works best. */
LightTree light_tree(scene, dscene, progress, 8);
LightTreeNode *root = light_tree.build(scene, dscene);
/* We want to create separate arrays corresponding to triangles and lights,
* which will be used to index back into the light tree for PDF calculations. */
uint *light_array = dscene->light_to_tree.alloc(kintegrator->num_lights);
uint *triangle_array = dscene->triangle_to_tree.alloc(light_tree.num_triangles);
/* First initialize the light tree's nodes. */
const size_t num_emitters = light_tree.num_emitters();
KernelLightTreeNode *light_tree_nodes = dscene->light_tree_nodes.alloc(light_tree.num_nodes);
KernelLightTreeEmitter *light_tree_emitters = dscene->light_tree_emitters.alloc(num_emitters);
/* Update integrator state. */
kintegrator->use_direct_light = num_emitters > 0;
/* Copy the light tree nodes to an array in the device. */
/* The nodes are arranged in a depth-first order, meaning the left child of each inner node
* always comes immediately after that inner node in the array, so that we only need to store the
* index of the right child.
* To do so, we repeatedly move to the left child of the current node until we reach the leftmost
* descendant, while keeping track of the right child of each node we visited by storing the
* pointer in the `right_node_stack`.
* Once finished visiting the left subtree, we retrieve the last stored pointer from
* `right_node_stack`, assign it to its parent (retrieved from `left_index_stack`), and repeat
* the process from there. */
int left_index_stack[32]; /* `sizeof(bit_trail) * 8 == 32`. */
LightTreeNode *right_node_stack[32];
int stack_id = 0;
const LightTreeNode *node = root;
for (int node_index = 0; node_index < light_tree.num_nodes; node_index++) {
light_tree_nodes[node_index].energy = node->measure.energy;
light_tree_nodes[node_index].bbox.min = node->measure.bbox.min;
light_tree_nodes[node_index].bbox.max = node->measure.bbox.max;
light_tree_nodes[node_index].bcone.axis = node->measure.bcone.axis;
light_tree_nodes[node_index].bcone.theta_o = node->measure.bcone.theta_o;
light_tree_nodes[node_index].bcone.theta_e = node->measure.bcone.theta_e;
light_tree_nodes[node_index].bit_trail = node->bit_trail;
light_tree_nodes[node_index].num_emitters = node->num_emitters;
/* Here we need to make a distinction between interior and leaf nodes. */
if (node->is_leaf()) {
light_tree_nodes[node_index].child_index = -node->first_emitter_index;
for (int i = 0; i < node->num_emitters; i++) {
int emitter_index = i + node->first_emitter_index;
const LightTreeEmitter &emitter = light_tree.get_emitter(emitter_index);
light_tree_emitters[emitter_index].energy = emitter.measure.energy;
light_tree_emitters[emitter_index].theta_o = emitter.measure.bcone.theta_o;
light_tree_emitters[emitter_index].theta_e = emitter.measure.bcone.theta_e;
if (emitter.is_triangle()) {
light_tree_emitters[emitter_index].mesh_light.object_id = emitter.object_id;
int shader_flag = 0;
Object *object = scene->objects[emitter.object_id];
Mesh *mesh = static_cast<Mesh *>(object->get_geometry());
Shader *shader = static_cast<Shader *>(
mesh->get_used_shaders()[mesh->get_shader()[emitter.prim_id]]);
if (!(object->get_visibility() & PATH_RAY_CAMERA)) {
shader_flag |= SHADER_EXCLUDE_CAMERA;
}
if (!(object->get_visibility() & PATH_RAY_DIFFUSE)) {
shader_flag |= SHADER_EXCLUDE_DIFFUSE;
}
if (!(object->get_visibility() & PATH_RAY_GLOSSY)) {
shader_flag |= SHADER_EXCLUDE_GLOSSY;
}
if (!(object->get_visibility() & PATH_RAY_TRANSMIT)) {
shader_flag |= SHADER_EXCLUDE_TRANSMIT;
}
if (!(object->get_visibility() & PATH_RAY_VOLUME_SCATTER)) {
shader_flag |= SHADER_EXCLUDE_SCATTER;
}
if (!(object->get_is_shadow_catcher())) {
shader_flag |= SHADER_EXCLUDE_SHADOW_CATCHER;
}
light_tree_emitters[emitter_index].prim_id = emitter.prim_id + mesh->prim_offset;
light_tree_emitters[emitter_index].mesh_light.shader_flag = shader_flag;
light_tree_emitters[emitter_index].emission_sampling = shader->emission_sampling;
triangle_array[emitter.prim_id + dscene->object_lookup_offset[emitter.object_id]] =
emitter_index;
}
else {
light_tree_emitters[emitter_index].prim_id = emitter.prim_id;
light_tree_emitters[emitter_index].mesh_light.shader_flag = 0;
light_tree_emitters[emitter_index].mesh_light.object_id = OBJECT_NONE;
light_tree_emitters[emitter_index].emission_sampling = EMISSION_SAMPLING_FRONT_BACK;
light_array[~emitter.prim_id] = emitter_index;
}
light_tree_emitters[emitter_index].parent_index = node_index;
}
/* Retrieve from the stacks. */
if (stack_id == 0) {
break;
}
stack_id--;
light_tree_nodes[left_index_stack[stack_id]].child_index = node_index + 1;
node = right_node_stack[stack_id];
}
else {
/* Fill in the stacks. */
left_index_stack[stack_id] = node_index;
right_node_stack[stack_id] = node->children[LightTree::right].get();
node = node->children[LightTree::left].get();
stack_id++;
}
}
/* Copy arrays to device. */
dscene->light_tree_nodes.copy_to_device();
dscene->light_tree_emitters.copy_to_device();
dscene->light_to_tree.copy_to_device();
dscene->triangle_to_tree.copy_to_device();
}
static void background_cdf(
int start, int end, int res_x, int res_y, const vector<float3> *pixels, float2 *cond_cdf)
{
int cdf_width = res_x + 1;
/* Conditional CDFs (rows, U direction). */
for (int i = start; i < end; i++) {
float sin_theta = sinf(M_PI_F * (i + 0.5f) / res_y);
float3 env_color = (*pixels)[i * res_x];
float ave_luminance = average(env_color);
cond_cdf[i * cdf_width].x = ave_luminance * sin_theta;
cond_cdf[i * cdf_width].y = 0.0f;
for (int j = 1; j < res_x; j++) {
env_color = (*pixels)[i * res_x + j];
ave_luminance = average(env_color);
cond_cdf[i * cdf_width + j].x = ave_luminance * sin_theta;
cond_cdf[i * cdf_width + j].y = cond_cdf[i * cdf_width + j - 1].y +
cond_cdf[i * cdf_width + j - 1].x / res_x;
}
const float cdf_total = cond_cdf[i * cdf_width + res_x - 1].y +
cond_cdf[i * cdf_width + res_x - 1].x / res_x;
/* stuff the total into the brightness value for the last entry, because
* we are going to normalize the CDFs to 0.0 to 1.0 afterwards */
cond_cdf[i * cdf_width + res_x].x = cdf_total;
if (cdf_total > 0.0f) {
const float cdf_total_inv = 1.0f / cdf_total;
for (int j = 1; j < res_x; j++) {
cond_cdf[i * cdf_width + j].y *= cdf_total_inv;
}
}
cond_cdf[i * cdf_width + res_x].y = 1.0f;
}
}
void LightManager::device_update_background(Device *device,
DeviceScene *dscene,
Scene *scene,
Progress &progress)
{
KernelIntegrator *kintegrator = &dscene->data.integrator;
KernelBackground *kbackground = &dscene->data.background;
Light *background_light = NULL;
bool background_mis = false;
/* find background light */
foreach (Light *light, scene->lights) {
if (light->light_type == LIGHT_BACKGROUND && light->is_enabled) {
background_light = light;
background_mis |= light->use_mis;
}
}
kbackground->portal_weight = kintegrator->num_portals > 0 ? 1.0f : 0.0f;
kbackground->map_weight = background_mis ? 1.0f : 0.0f;
kbackground->sun_weight = 0.0f;
/* no background light found, signal renderer to skip sampling */
if (!background_light || !background_light->is_enabled) {
kbackground->map_res_x = 0;
kbackground->map_res_y = 0;
kbackground->use_mis = (kbackground->portal_weight > 0.0f);
return;
}
progress.set_status("Updating Lights", "Importance map");
int2 environment_res = make_int2(0, 0);
Shader *shader = scene->background->get_shader(scene);
int num_suns = 0;
float sun_average_radiance = 0.0f;
foreach (ShaderNode *node, shader->graph->nodes) {
if (node->type == EnvironmentTextureNode::get_node_type()) {
EnvironmentTextureNode *env = (EnvironmentTextureNode *)node;
if (!env->handle.empty()) {
ImageMetaData metadata = env->handle.metadata();
environment_res.x = max(environment_res.x, (int)metadata.width);
environment_res.y = max(environment_res.y, (int)metadata.height);
}
}
if (node->type == SkyTextureNode::get_node_type()) {
SkyTextureNode *sky = (SkyTextureNode *)node;
if (sky->get_sky_type() == NODE_SKY_NISHITA && sky->get_sun_disc()) {
/* Ensure that the input coordinates aren't transformed before they reach the node.
* If that is the case, the logic used for sampling the sun's location does not work
* and we have to fall back to map-based sampling. */
const ShaderInput *vec_in = sky->input("Vector");
if (vec_in && vec_in->link && vec_in->link->parent) {
ShaderNode *vec_src = vec_in->link->parent;
if ((vec_src->type != TextureCoordinateNode::get_node_type()) ||
(vec_in->link != vec_src->output("Generated"))) {
environment_res.x = max(environment_res.x, 4096);
environment_res.y = max(environment_res.y, 2048);
continue;
}
}
/* Determine sun direction from lat/long and texture mapping. */
float latitude = sky->get_sun_elevation();
float longitude = M_2PI_F - sky->get_sun_rotation() + M_PI_2_F;
float3 sun_direction = make_float3(
cosf(latitude) * cosf(longitude), cosf(latitude) * sinf(longitude), sinf(latitude));
Transform sky_transform = transform_inverse(sky->tex_mapping.compute_transform());
sun_direction = transform_direction(&sky_transform, sun_direction);
/* Pack sun direction and size. */
float half_angle = sky->get_sun_size() * 0.5f;
kbackground->sun = make_float4(
sun_direction.x, sun_direction.y, sun_direction.z, half_angle);
/* empirical value */
kbackground->sun_weight = 4.0f;
sun_average_radiance = sky->get_sun_average_radiance();
environment_res.x = max(environment_res.x, 512);
environment_res.y = max(environment_res.y, 256);
num_suns++;
}
}
}
/* If there's more than one sun, fall back to map sampling instead. */
if (num_suns != 1) {
kbackground->sun_weight = 0.0f;
environment_res.x = max(environment_res.x, 4096);
environment_res.y = max(environment_res.y, 2048);
}
/* Enable MIS for background sampling if any strategy is active. */
kbackground->use_mis = (kbackground->portal_weight + kbackground->map_weight +
kbackground->sun_weight) > 0.0f;
/* get the resolution from the light's size (we stuff it in there) */
int2 res = make_int2(background_light->map_resolution, background_light->map_resolution / 2);
/* If the resolution isn't set manually, try to find an environment texture. */
if (res.x == 0) {
res = environment_res;
if (res.x > 0 && res.y > 0) {
VLOG_INFO << "Automatically set World MIS resolution to " << res.x << " by " << res.y
<< "\n";
}
}
/* If it's still unknown, just use the default. */
if (res.x == 0 || res.y == 0) {
res = make_int2(1024, 512);
VLOG_INFO << "Setting World MIS resolution to default\n";
}
kbackground->map_res_x = res.x;
kbackground->map_res_y = res.y;
vector<float3> pixels;
shade_background_pixels(device, dscene, res.x, res.y, pixels, progress);
if (progress.get_cancel())
return;
/* build row distributions and column distribution for the infinite area environment light */
int cdf_width = res.x + 1;
float2 *marg_cdf = dscene->light_background_marginal_cdf.alloc(res.y + 1);
float2 *cond_cdf = dscene->light_background_conditional_cdf.alloc(cdf_width * res.y);
double time_start = time_dt();
/* Create CDF in parallel. */
const int rows_per_task = divide_up(10240, res.x);
parallel_for(blocked_range<size_t>(0, res.y, rows_per_task),
[&](const blocked_range<size_t> &r) {
background_cdf(r.begin(), r.end(), res.x, res.y, &pixels, cond_cdf);
});
/* marginal CDFs (column, V direction, sum of rows) */
marg_cdf[0].x = cond_cdf[res.x].x;
marg_cdf[0].y = 0.0f;
for (int i = 1; i < res.y; i++) {
marg_cdf[i].x = cond_cdf[i * cdf_width + res.x].x;
marg_cdf[i].y = marg_cdf[i - 1].y + marg_cdf[i - 1].x / res.y;
}
float cdf_total = marg_cdf[res.y - 1].y + marg_cdf[res.y - 1].x / res.y;
marg_cdf[res.y].x = cdf_total;
float map_average_radiance = cdf_total * M_PI_2_F;
if (sun_average_radiance > 0.0f) {
/* The weighting here is just a heuristic that was empirically determined.
* The sun's average radiance is much higher than the map's average radiance,
* but we don't want to weight the background light too much because
* visibility is not accounted for anyway. */
background_light->set_average_radiance(0.8f * map_average_radiance +
0.2f * sun_average_radiance);
}
else {
background_light->set_average_radiance(map_average_radiance);
}
if (cdf_total > 0.0f)
for (int i = 1; i < res.y; i++)
marg_cdf[i].y /= cdf_total;
marg_cdf[res.y].y = 1.0f;
VLOG_WORK << "Background MIS build time " << time_dt() - time_start << "\n";
/* update device */
dscene->light_background_marginal_cdf.copy_to_device();
dscene->light_background_conditional_cdf.copy_to_device();
}
void LightManager::device_update_lights(Device *device, DeviceScene *dscene, Scene *scene)
{
/* Counts lights in the scene. */
size_t num_lights = 0;
size_t num_portals = 0;
size_t num_background_lights = 0;
size_t num_distant_lights = 0;
bool use_light_mis = false;
foreach (Light *light, scene->lights) {
if (light->is_enabled) {
num_lights++;
if (light->light_type == LIGHT_DISTANT) {
num_distant_lights++;
}
else if (light->light_type == LIGHT_POINT || light->light_type == LIGHT_SPOT) {
use_light_mis |= (light->size > 0.0f && light->use_mis);
}
else if (light->light_type == LIGHT_AREA) {
use_light_mis |= light->use_mis;
}
else if (light->light_type == LIGHT_BACKGROUND) {
num_distant_lights++;
num_background_lights++;
}
}
if (light->is_portal) {
num_portals++;
}
}
/* Update integrator settings. */
KernelIntegrator *kintegrator = &dscene->data.integrator;
kintegrator->use_light_tree = scene->integrator->get_use_light_tree() &&
device->info.has_light_tree;
kintegrator->num_lights = num_lights;
kintegrator->num_distant_lights = num_distant_lights;
kintegrator->num_background_lights = num_background_lights;
kintegrator->use_light_mis = use_light_mis;
kintegrator->num_portals = num_portals;
kintegrator->portal_offset = num_lights;
/* Create KernelLight for every portal and enabled light in the scene. */
KernelLight *klights = dscene->lights.alloc(num_lights + num_portals);
int light_index = 0;
int portal_index = num_lights;
foreach (Light *light, scene->lights) {
/* Consider moving portals update to their own function
* keeping this one more manageable. */
if (light->is_portal) {
assert(light->light_type == LIGHT_AREA);
float3 extentu = light->axisu * (light->sizeu * light->size);
float3 extentv = light->axisv * (light->sizev * light->size);
float len_u, len_v;
float3 axis_u = normalize_len(extentu, &len_u);
float3 axis_v = normalize_len(extentv, &len_v);
float area = len_u * len_v;
if (light->ellipse) {
area *= -M_PI_4_F;
}
float invarea = (area != 0.0f) ? 1.0f / area : 1.0f;
float3 dir = light->dir;
dir = safe_normalize(dir);
klights[portal_index].co = light->co;
klights[portal_index].area.axis_u = axis_u;
klights[portal_index].area.len_u = len_u;
klights[portal_index].area.axis_v = axis_v;
klights[portal_index].area.len_v = len_v;
klights[portal_index].area.invarea = invarea;
klights[portal_index].area.dir = dir;
klights[portal_index].tfm = light->tfm;
klights[portal_index].itfm = transform_inverse(light->tfm);
portal_index++;
continue;
}
if (!light->is_enabled) {
continue;
}
float3 co = light->co;
Shader *shader = (light->shader) ? light->shader : scene->default_light;
int shader_id = scene->shader_manager->get_shader_id(shader);
int max_bounces = light->max_bounces;
float random = (float)light->random_id * (1.0f / (float)0xFFFFFFFF);
if (!light->cast_shadow)
shader_id &= ~SHADER_CAST_SHADOW;
if (!light->use_camera) {
shader_id |= SHADER_EXCLUDE_CAMERA;
}
if (!light->use_diffuse) {
shader_id |= SHADER_EXCLUDE_DIFFUSE;
}
if (!light->use_glossy) {
shader_id |= SHADER_EXCLUDE_GLOSSY;
}
if (!light->use_transmission) {
shader_id |= SHADER_EXCLUDE_TRANSMIT;
}
if (!light->use_scatter) {
shader_id |= SHADER_EXCLUDE_SCATTER;
}
if (!light->is_shadow_catcher) {
shader_id |= SHADER_EXCLUDE_SHADOW_CATCHER;
}
klights[light_index].type = light->light_type;
klights[light_index].strength[0] = light->strength.x;
klights[light_index].strength[1] = light->strength.y;
klights[light_index].strength[2] = light->strength.z;
if (light->light_type == LIGHT_POINT) {
shader_id &= ~SHADER_AREA_LIGHT;
float radius = light->size;
float invarea = (light->normalize && radius > 0.0f) ? 1.0f / (M_PI_F * radius * radius) :
1.0f;
if (light->use_mis && radius > 0.0f)
shader_id |= SHADER_USE_MIS;
klights[light_index].co = co;
klights[light_index].spot.radius = radius;
klights[light_index].spot.invarea = invarea;
}
else if (light->light_type == LIGHT_DISTANT) {
shader_id &= ~SHADER_AREA_LIGHT;
float angle = light->angle / 2.0f;
float radius = tanf(angle);
float cosangle = cosf(angle);
float area = M_PI_F * radius * radius;
float invarea = (light->normalize && area > 0.0f) ? 1.0f / area : 1.0f;
float3 dir = light->dir;
dir = safe_normalize(dir);
if (light->use_mis && area > 0.0f)
shader_id |= SHADER_USE_MIS;
klights[light_index].co = dir;
klights[light_index].distant.invarea = invarea;
klights[light_index].distant.radius = radius;
klights[light_index].distant.cosangle = cosangle;
}
else if (light->light_type == LIGHT_BACKGROUND) {
uint visibility = scene->background->get_visibility();
dscene->data.background.light_index = light_index;
shader_id &= ~SHADER_AREA_LIGHT;
shader_id |= SHADER_USE_MIS;
if (!(visibility & PATH_RAY_DIFFUSE)) {
shader_id |= SHADER_EXCLUDE_DIFFUSE;
}
if (!(visibility & PATH_RAY_GLOSSY)) {
shader_id |= SHADER_EXCLUDE_GLOSSY;
}
if (!(visibility & PATH_RAY_TRANSMIT)) {
shader_id |= SHADER_EXCLUDE_TRANSMIT;
}
if (!(visibility & PATH_RAY_VOLUME_SCATTER)) {
shader_id |= SHADER_EXCLUDE_SCATTER;
}
}
else if (light->light_type == LIGHT_AREA) {
float3 extentu = light->axisu * (light->sizeu * light->size);
float3 extentv = light->axisv * (light->sizev * light->size);
float len_u, len_v;
float3 axis_u = normalize_len(extentu, &len_u);
float3 axis_v = normalize_len(extentv, &len_v);
float area = len_u * len_v;
if (light->ellipse) {
area *= -M_PI_4_F;
}
float invarea = (light->normalize && area != 0.0f) ? 1.0f / area : 1.0f;
float3 dir = light->dir;
/* Clamp angles in (0, 0.1) to 0.1 to prevent zero intensity due to floating-point precision
* issues, but still handles spread = 0 */
const float min_spread = 0.1f * M_PI_F / 180.0f;
const float half_spread = light->spread == 0 ? 0.0f : 0.5f * max(light->spread, min_spread);
const float tan_half_spread = light->spread == M_PI_F ? FLT_MAX : tanf(half_spread);
/* Normalization computed using:
* integrate cos(x) * (1 - tan(x) / tan(a)) * sin(x) from x = 0 to a, a being half_spread.
* Divided by tan_half_spread to simplify the attenuation computation in `area.h`. */
const float normalize_spread = 1.0f / (tan_half_spread - half_spread);
dir = safe_normalize(dir);
if (light->use_mis && area != 0.0f)
shader_id |= SHADER_USE_MIS;
klights[light_index].co = co;
klights[light_index].area.axis_u = axis_u;
klights[light_index].area.len_u = len_u;
klights[light_index].area.axis_v = axis_v;
klights[light_index].area.len_v = len_v;
klights[light_index].area.invarea = invarea;
klights[light_index].area.dir = dir;
klights[light_index].area.tan_half_spread = tan_half_spread;
klights[light_index].area.normalize_spread = normalize_spread;
}
else if (light->light_type == LIGHT_SPOT) {
shader_id &= ~SHADER_AREA_LIGHT;
float3 len;
float3 axis_u = normalize_len(light->axisu, &len.x);
float3 axis_v = normalize_len(light->axisv, &len.y);
float3 dir = normalize_len(light->dir, &len.z);
if (len.z == 0.0f) {
dir = zero_float3();
}
float radius = light->size;
float invarea = (light->normalize && radius > 0.0f) ? 1.0f / (M_PI_F * radius * radius) :
1.0f;
float cos_half_spot_angle = cosf(light->spot_angle * 0.5f);
float spot_smooth = (1.0f - cos_half_spot_angle) * light->spot_smooth;
if (light->use_mis && radius > 0.0f)
shader_id |= SHADER_USE_MIS;
klights[light_index].co = co;
klights[light_index].spot.axis_u = axis_u;
klights[light_index].spot.radius = radius;
klights[light_index].spot.axis_v = axis_v;
klights[light_index].spot.invarea = invarea;
klights[light_index].spot.dir = dir;
klights[light_index].spot.cos_half_spot_angle = cos_half_spot_angle;
klights[light_index].spot.len = len;
klights[light_index].spot.spot_smooth = spot_smooth;
}
klights[light_index].shader_id = shader_id;
klights[light_index].max_bounces = max_bounces;
klights[light_index].random = random;
klights[light_index].use_caustics = light->use_caustics;
klights[light_index].tfm = light->tfm;
klights[light_index].itfm = transform_inverse(light->tfm);
auto it = scene->lightgroups.find(light->lightgroup);
if (it != scene->lightgroups.end()) {
klights[light_index].lightgroup = it->second;
}
else {
klights[light_index].lightgroup = LIGHTGROUP_NONE;
}
light_index++;
}
VLOG_INFO << "Number of lights sent to the device: " << num_lights;
dscene->lights.copy_to_device();
}
void LightManager::device_update(Device *device,
DeviceScene *dscene,
Scene *scene,
Progress &progress)
{
if (!need_update())
return;
scoped_callback_timer timer([scene](double time) {
if (scene->update_stats) {
scene->update_stats->light.times.add_entry({"device_update", time});
}
});
VLOG_INFO << "Total " << scene->lights.size() << " lights.";
/* Detect which lights are enabled, also determines if we need to update the background. */
test_enabled_lights(scene);
device_free(device, dscene, need_update_background);
device_update_lights(device, dscene, scene);
if (progress.get_cancel())
return;
if (need_update_background) {
device_update_background(device, dscene, scene, progress);
if (progress.get_cancel())
return;
}
device_update_distribution(device, dscene, scene, progress);
if (progress.get_cancel())
return;
device_update_tree(device, dscene, scene, progress);
if (progress.get_cancel())
return;
device_update_ies(dscene);
if (progress.get_cancel())
return;
update_flags = UPDATE_NONE;
need_update_background = false;
}
void LightManager::device_free(Device *, DeviceScene *dscene, const bool free_background)
{
dscene->light_tree_nodes.free();
dscene->light_tree_emitters.free();
dscene->light_to_tree.free();
dscene->object_lookup_offset.free();
dscene->triangle_to_tree.free();
dscene->light_distribution.free();
dscene->lights.free();
if (free_background) {
dscene->light_background_marginal_cdf.free();
dscene->light_background_conditional_cdf.free();
}
dscene->ies_lights.free();
}
void LightManager::tag_update(Scene * /*scene*/, uint32_t flag)
{
update_flags |= flag;
}
bool LightManager::need_update() const
{
return update_flags != UPDATE_NONE;
}
int LightManager::add_ies_from_file(const string &filename)
{
string content;
/* If the file can't be opened, call with an empty line */
if (filename.empty() || !path_read_text(filename.c_str(), content)) {
content = "\n";
}
return add_ies(content);
}
int LightManager::add_ies(const string &content)
{
uint hash = hash_string(content.c_str());
thread_scoped_lock ies_lock(ies_mutex);
/* Check whether this IES already has a slot. */
size_t slot;
for (slot = 0; slot < ies_slots.size(); slot++) {
if (ies_slots[slot]->hash == hash) {
ies_slots[slot]->users++;
return slot;
}
}
/* Try to find an empty slot for the new IES. */
for (slot = 0; slot < ies_slots.size(); slot++) {
if (ies_slots[slot]->users == 0 && ies_slots[slot]->hash == 0) {
break;
}
}
/* If there's no free slot, add one. */
if (slot == ies_slots.size()) {
ies_slots.push_back(new IESSlot());
}
ies_slots[slot]->ies.load(content);
ies_slots[slot]->users = 1;
ies_slots[slot]->hash = hash;
update_flags = UPDATE_ALL;
need_update_background = true;
return slot;
}
void LightManager::remove_ies(int slot)
{
thread_scoped_lock ies_lock(ies_mutex);
if (slot < 0 || slot >= ies_slots.size()) {
assert(false);
return;
}
assert(ies_slots[slot]->users > 0);
ies_slots[slot]->users--;
/* If the slot has no more users, update the device to remove it. */
if (ies_slots[slot]->users == 0) {
update_flags |= UPDATE_ALL;
need_update_background = true;
}
}
void LightManager::device_update_ies(DeviceScene *dscene)
{
/* Clear empty slots. */
foreach (IESSlot *slot, ies_slots) {
if (slot->users == 0) {
slot->hash = 0;
slot->ies.clear();
}
}
/* Shrink the slot table by removing empty slots at the end. */
int slot_end;
for (slot_end = ies_slots.size(); slot_end; slot_end--) {
if (ies_slots[slot_end - 1]->users > 0) {
/* If the preceding slot has users, we found the new end of the table. */
break;
}
else {
/* The slot will be past the new end of the table, so free it. */
delete ies_slots[slot_end - 1];
}
}
ies_slots.resize(slot_end);
if (ies_slots.size() > 0) {
int packed_size = 0;
foreach (IESSlot *slot, ies_slots) {
packed_size += slot->ies.packed_size();
}
/* ies_lights starts with an offset table that contains the offset of every slot,
* or -1 if the slot is invalid.
* Following that table, the packed valid IES lights are stored. */
float *data = dscene->ies_lights.alloc(ies_slots.size() + packed_size);
int offset = ies_slots.size();
for (int i = 0; i < ies_slots.size(); i++) {
int size = ies_slots[i]->ies.packed_size();
if (size > 0) {
data[i] = __int_as_float(offset);
ies_slots[i]->ies.pack(data + offset);
offset += size;
}
else {
data[i] = __int_as_float(-1);
}
}
dscene->ies_lights.copy_to_device();
}
}
CCL_NAMESPACE_END