blender/intern/cycles/render/light.cpp
Brecht Van Lommel 4ba456d175 Cycles: first step for implementation of non-progressive sampler that handles
direct and indirect lighting differently. Rather than picking one light for each
point on the path, it now loops over all lights for direct lighting. For indirect
lighting it still picks a random light each time.

It gives control over the number of AA samples, and the number of Diffuse, Glossy,
Transmission, AO, Mesh Light, Background and Lamp samples for each AA sample.

This helps tuning render performance/noise and tends to give less noise for renders
dominated by direct lighting.

This sampling mode only works on the CPU, and still needs proper tile rendering
to show progress (will follow tommorrow or so), because each AA sample can be quite
slow now and so the delay between each update wil be too long.
2012-06-13 11:44:48 +00:00

497 lines
14 KiB
C++

/*
* Copyright 2011, Blender Foundation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "device.h"
#include "integrator.h"
#include "light.h"
#include "mesh.h"
#include "object.h"
#include "scene.h"
#include "shader.h"
#include "util_foreach.h"
#include "util_progress.h"
CCL_NAMESPACE_BEGIN
static void dump_background_pixels(Device *device, DeviceScene *dscene, int res, vector<float3>& pixels)
{
/* create input */
int width = res;
int height = res;
device_vector<uint4> d_input;
device_vector<float4> d_output;
uint4 *d_input_data = d_input.resize(width*height);
for(int y = 0; y < height; y++) {
for(int x = 0; x < width; x++) {
float u = x/(float)width;
float v = y/(float)height;
uint4 in = make_uint4(__float_as_int(u), __float_as_int(v), 0, 0);
d_input_data[x + y*width] = in;
}
}
/* compute on device */
float4 *d_output_data = d_output.resize(width*height);
memset((void*)d_output.data_pointer, 0, d_output.memory_size());
device->const_copy_to("__data", &dscene->data, sizeof(dscene->data));
device->mem_alloc(d_input, MEM_READ_ONLY);
device->mem_copy_to(d_input);
device->mem_alloc(d_output, MEM_WRITE_ONLY);
DeviceTask main_task(DeviceTask::SHADER);
main_task.shader_input = d_input.device_pointer;
main_task.shader_output = d_output.device_pointer;
main_task.shader_eval_type = SHADER_EVAL_BACKGROUND;
main_task.shader_x = 0;
main_task.shader_w = width*height;
list<DeviceTask> split_tasks;
main_task.split_max_size(split_tasks, 128*128);
foreach(DeviceTask& task, split_tasks) {
device->task_add(task);
device->task_wait();
}
device->mem_copy_from(d_output, 0, 1, d_output.size(), sizeof(float4));
device->mem_free(d_input);
device->mem_free(d_output);
d_output_data = reinterpret_cast<float4*>(d_output.data_pointer);
pixels.resize(width*height);
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].x;
pixels[y*width + x].y = d_output_data[y*width + x].y;
pixels[y*width + x].z = d_output_data[y*width + x].z;
}
}
}
/* Light */
Light::Light()
{
type = LIGHT_POINT;
co = make_float3(0.0f, 0.0f, 0.0f);
dir = make_float3(0.0f, 0.0f, 0.0f);
size = 0.0f;
axisu = make_float3(0.0f, 0.0f, 0.0f);
sizeu = 1.0f;
axisv = make_float3(0.0f, 0.0f, 0.0f);
sizev = 1.0f;
map_resolution = 512;
spot_angle = M_PI_F/4.0f;
spot_smooth = 0.0f;
cast_shadow = true;
shader = 0;
samples = 1;
}
void Light::tag_update(Scene *scene)
{
scene->light_manager->need_update = true;
}
/* Light Manager */
LightManager::LightManager()
{
need_update = true;
}
LightManager::~LightManager()
{
}
void LightManager::device_update_distribution(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
{
progress.set_status("Updating Lights", "Computing distribution");
/* count */
size_t num_lights = scene->lights.size();
size_t num_triangles = 0;
foreach(Object *object, scene->objects) {
Mesh *mesh = object->mesh;
bool have_emission = false;
/* skip if we have no emission shaders */
foreach(uint sindex, mesh->used_shaders) {
Shader *shader = scene->shaders[sindex];
if(shader->sample_as_light && shader->has_surface_emission) {
have_emission = true;
break;
}
}
/* count triangles */
if(have_emission) {
for(size_t i = 0; i < mesh->triangles.size(); i++) {
Shader *shader = scene->shaders[mesh->shader[i]];
if(shader->sample_as_light && shader->has_surface_emission)
num_triangles++;
}
}
}
size_t num_distribution = num_triangles;
num_distribution += num_lights;
/* emission area */
float4 *distribution = dscene->light_distribution.resize(num_distribution + 1);
float totarea = 0.0f;
/* triangles */
size_t offset = 0;
int j = 0;
foreach(Object *object, scene->objects) {
Mesh *mesh = object->mesh;
bool have_emission = false;
/* skip if we have no emission shaders */
foreach(uint sindex, mesh->used_shaders) {
Shader *shader = scene->shaders[sindex];
if(shader->sample_as_light && shader->has_surface_emission) {
have_emission = true;
break;
}
}
/* sum area */
if(have_emission) {
Transform tfm = object->tfm;
int object_id = j;
if(mesh->transform_applied)
object_id = ~object_id;
for(size_t i = 0; i < mesh->triangles.size(); i++) {
Shader *shader = scene->shaders[mesh->shader[i]];
if(shader->sample_as_light && shader->has_surface_emission) {
distribution[offset].x = totarea;
distribution[offset].y = __int_as_float(i + mesh->tri_offset);
distribution[offset].z = 1.0f;
distribution[offset].w = __int_as_float(object_id);
offset++;
Mesh::Triangle t = mesh->triangles[i];
float3 p1 = transform_point(&tfm, mesh->verts[t.v[0]]);
float3 p2 = transform_point(&tfm, mesh->verts[t.v[1]]);
float3 p3 = transform_point(&tfm, mesh->verts[t.v[2]]);
totarea += triangle_area(p1, p2, p3);
}
}
}
if(progress.get_cancel()) return;
j++;
}
float trianglearea = totarea;
/* point lights */
float lightarea = (totarea > 0.0f)? totarea/scene->lights.size(): 1.0f;
for(int i = 0; i < scene->lights.size(); i++, offset++) {
distribution[offset].x = totarea;
distribution[offset].y = __int_as_float(~(int)i);
distribution[offset].z = 1.0f;
distribution[offset].w = scene->lights[i]->size;
totarea += lightarea;
}
/* normalize cumulative distribution functions */
distribution[num_distribution].x = totarea;
distribution[num_distribution].y = 0.0f;
distribution[num_distribution].z = 0.0f;
distribution[num_distribution].w = 0.0f;
if(totarea > 0.0f) {
for(size_t i = 0; i < num_distribution; i++)
distribution[i].x /= totarea;
distribution[num_distribution].x = 1.0f;
}
if(progress.get_cancel()) return;
/* update device */
KernelIntegrator *kintegrator = &dscene->data.integrator;
kintegrator->use_direct_light = (totarea > 0.0f);
if(kintegrator->use_direct_light) {
/* number of emissives */
kintegrator->num_distribution = (totarea > 0.0f)? num_distribution: 0;
/* precompute pdfs */
kintegrator->pdf_triangles = 0.0f;
kintegrator->pdf_lights = 0.0f;
/* sample one, with 0.5 probability of light or triangle */
kintegrator->num_all_lights = num_lights;
if(trianglearea > 0.0f) {
kintegrator->pdf_triangles = 1.0f/trianglearea;
if(num_lights)
kintegrator->pdf_triangles *= 0.5f;
}
if(num_lights) {
kintegrator->pdf_lights = 1.0f/num_lights;
if(trianglearea > 0.0f)
kintegrator->pdf_lights *= 0.5f;
}
/* CDF */
device->tex_alloc("__light_distribution", dscene->light_distribution);
}
else
dscene->light_distribution.clear();
}
void LightManager::device_update_background(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
{
KernelIntegrator *kintegrator = &dscene->data.integrator;
Light *background_light = NULL;
/* find background light */
foreach(Light *light, scene->lights) {
if(light->type == LIGHT_BACKGROUND) {
background_light = light;
break;
}
}
/* no background light found, signal renderer to skip sampling */
if(!background_light) {
kintegrator->pdf_background_res = 0;
return;
}
progress.set_status("Updating Lights", "Importance map");
assert(kintegrator->use_direct_light);
/* get the resolution from the light's size (we stuff it in there) */
int res = background_light->map_resolution;
kintegrator->pdf_background_res = res;
assert(res > 0);
vector<float3> pixels;
dump_background_pixels(device, dscene, res, pixels);
if(progress.get_cancel())
return;
/* build row distributions and column distribution for the infinite area environment light */
int cdf_count = res + 1;
float2 *marg_cdf = dscene->light_background_marginal_cdf.resize(cdf_count);
float2 *cond_cdf = dscene->light_background_conditional_cdf.resize(cdf_count * cdf_count);
/* conditional CDFs (rows, U direction) */
for(int i = 0; i < res; i++) {
float sin_theta = sinf(M_PI_F * (i + 0.5f) / res);
float3 env_color = pixels[i * res];
float ave_luminamce = average(env_color);
cond_cdf[i * cdf_count].x = ave_luminamce * sin_theta;
cond_cdf[i * cdf_count].y = 0.0f;
for(int j = 1; j < res; j++) {
env_color = pixels[i * res + j];
ave_luminamce = average(env_color);
cond_cdf[i * cdf_count + j].x = ave_luminamce * sin_theta;
cond_cdf[i * cdf_count + j].y = cond_cdf[i * cdf_count + j - 1].y + cond_cdf[i * cdf_count + j - 1].x / res;
}
float cdf_total = cond_cdf[i * cdf_count + res - 1].y + cond_cdf[i * cdf_count + res - 1].x / res;
/* 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_count + res].x = cdf_total;
if(cdf_total > 0.0f)
for(int j = 1; j < res; j++)
cond_cdf[i * cdf_count + j].y /= cdf_total;
cond_cdf[i * cdf_count + res].y = 1.0f;
}
/* marginal CDFs (column, V direction, sum of rows) */
marg_cdf[0].x = cond_cdf[res].x;
marg_cdf[0].y = 0.0f;
for(int i = 1; i < res; i++) {
marg_cdf[i].x = cond_cdf[i * cdf_count + res].x;
marg_cdf[i].y = marg_cdf[i - 1].y + marg_cdf[i - 1].x / res;
}
float cdf_total = marg_cdf[res - 1].y + marg_cdf[res - 1].x / res;
marg_cdf[res].x = cdf_total;
if(cdf_total > 0.0f)
for(int i = 1; i < res; i++)
marg_cdf[i].y /= cdf_total;
marg_cdf[res].y = 1.0f;
/* update device */
device->tex_alloc("__light_background_marginal_cdf", dscene->light_background_marginal_cdf);
device->tex_alloc("__light_background_conditional_cdf", dscene->light_background_conditional_cdf);
}
void LightManager::device_update_points(Device *device, DeviceScene *dscene, Scene *scene)
{
if(scene->lights.size() == 0)
return;
float4 *light_data = dscene->light_data.resize(scene->lights.size()*LIGHT_SIZE);
if(!device->info.advanced_shading) {
/* remove unsupported light */
foreach(Light *light, scene->lights) {
if(light->type == LIGHT_BACKGROUND) {
scene->lights.erase(std::remove(scene->lights.begin(), scene->lights.end(), light), scene->lights.end());
break;
}
}
}
for(size_t i = 0; i < scene->lights.size(); i++) {
Light *light = scene->lights[i];
float3 co = light->co;
float3 dir = normalize(light->dir);
int shader_id = scene->shader_manager->get_shader_id(scene->lights[i]->shader);
float samples = __int_as_float(light->samples);
if(!light->cast_shadow)
shader_id &= ~SHADER_CAST_SHADOW;
if(light->type == LIGHT_POINT) {
shader_id &= ~SHADER_AREA_LIGHT;
light_data[i*LIGHT_SIZE + 0] = make_float4(__int_as_float(light->type), co.x, co.y, co.z);
light_data[i*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), light->size, 0.0f, 0.0f);
light_data[i*LIGHT_SIZE + 2] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
light_data[i*LIGHT_SIZE + 3] = make_float4(samples, 0.0f, 0.0f, 0.0f);
}
else if(light->type == LIGHT_DISTANT) {
shader_id &= ~SHADER_AREA_LIGHT;
light_data[i*LIGHT_SIZE + 0] = make_float4(__int_as_float(light->type), dir.x, dir.y, dir.z);
light_data[i*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), light->size, 0.0f, 0.0f);
light_data[i*LIGHT_SIZE + 2] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
light_data[i*LIGHT_SIZE + 3] = make_float4(samples, 0.0f, 0.0f, 0.0f);
}
else if(light->type == LIGHT_BACKGROUND) {
shader_id &= ~SHADER_AREA_LIGHT;
light_data[i*LIGHT_SIZE + 0] = make_float4(__int_as_float(light->type), 0.0f, 0.0f, 0.0f);
light_data[i*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), 0.0f, 0.0f, 0.0f);
light_data[i*LIGHT_SIZE + 2] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
light_data[i*LIGHT_SIZE + 3] = make_float4(samples, 0.0f, 0.0f, 0.0f);
}
else if(light->type == LIGHT_AREA) {
float3 axisu = light->axisu*(light->sizeu*light->size);
float3 axisv = light->axisv*(light->sizev*light->size);
light_data[i*LIGHT_SIZE + 0] = make_float4(__int_as_float(light->type), co.x, co.y, co.z);
light_data[i*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), axisu.x, axisu.y, axisu.z);
light_data[i*LIGHT_SIZE + 2] = make_float4(0.0f, axisv.x, axisv.y, axisv.z);
light_data[i*LIGHT_SIZE + 3] = make_float4(samples, dir.x, dir.y, dir.z);
}
else if(light->type == LIGHT_SPOT) {
shader_id &= ~SHADER_AREA_LIGHT;
float spot_angle = cosf(light->spot_angle*0.5f);
float spot_smooth = (1.0f - spot_angle)*light->spot_smooth;
light_data[i*LIGHT_SIZE + 0] = make_float4(__int_as_float(light->type), co.x, co.y, co.z);
light_data[i*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), light->size, dir.x, dir.y);
light_data[i*LIGHT_SIZE + 2] = make_float4(dir.z, spot_angle, spot_smooth, 0.0f);
light_data[i*LIGHT_SIZE + 3] = make_float4(samples, 0.0f, 0.0f, 0.0f);
}
}
device->tex_alloc("__light_data", dscene->light_data);
}
void LightManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
{
if(!need_update)
return;
device_free(device, dscene);
device_update_points(device, dscene, scene);
if(progress.get_cancel()) return;
device_update_distribution(device, dscene, scene, progress);
if(progress.get_cancel()) return;
device_update_background(device, dscene, scene, progress);
if(progress.get_cancel()) return;
need_update = false;
}
void LightManager::device_free(Device *device, DeviceScene *dscene)
{
device->tex_free(dscene->light_distribution);
device->tex_free(dscene->light_data);
device->tex_free(dscene->light_background_marginal_cdf);
device->tex_free(dscene->light_background_conditional_cdf);
dscene->light_distribution.clear();
dscene->light_data.clear();
dscene->light_background_marginal_cdf.clear();
dscene->light_background_conditional_cdf.clear();
}
void LightManager::tag_update(Scene *scene)
{
need_update = true;
}
CCL_NAMESPACE_END