glm::vec3 DirectLightingIntegrator::EstimateDirectLighting(const Intersection &isx, unsigned int &n_light, unsigned int &n_brdf, const glm::vec3 &woW)
{
//for Light source sampling
//QList<glm::vec3> light_sample_pts;
glm::vec3 brdf_sampling_final(0,0,0);
glm::vec3 light_sampling_final(0,0,0);
glm::vec3 color_final(0,0,0);
Intersection light_sample_isx; //randomly sampled intersection on the light source's surface
glm::vec3 wiW; // incoming ray in world frame
Ray light_sample_ray;
float rand1 = unif_distribution(mersenne_generator);
float rand2 = unif_distribution(mersenne_generator);
int light_choice = 0;
Intersection obstruction_test;
//for all light sources
//for (int i = 0; i < scene->lights.count(); i++)
//{
//light source sampling
for(unsigned int j = 0; j < n_light; j++)
{
light_choice = rand()%scene->lights.count();
light_sample_isx = scene->lights[light_choice]->GetRandISX(rand1, rand2, isx.normal); //take 1 sample point(intersection) on the light source for now
wiW = light_sample_isx.point - isx.point; //ray direction going from world point to light source
light_sample_isx.t = glm::length(wiW);
wiW = glm::normalize(wiW);
light_sample_ray = Ray(isx.point, wiW);//remember, the direction is from point in scene to light source
obstruction_test = intersection_engine->GetIntersection(light_sample_ray);
//update random point
rand1 = unif_distribution(mersenne_generator);
rand2 = unif_distribution(mersenne_generator);
if (obstruction_test.object_hit == scene->lights[light_choice])
{
light_sampling_final = light_sampling_final + LightPDFEnergy(obstruction_test, isx, light_sample_ray, woW, n_light, n_brdf);
}
else
{
//the ray contributes zero energy
}
}
light_sampling_final = light_sampling_final/static_cast<float>(n_light); //divide by samples taken
//light_sampling_final = light_sampling_final + light_sampling_temp; // accumulate energy per high source
//light_sampling_temp = glm::vec3(0, 0, 0);// zero out color_temp for the next light source
//}
//brdf sampling
for(unsigned int j = 0; j < n_brdf; j++)
{
brdf_sampling_final = brdf_sampling_final + BxDFPDFEnergy(isx, woW, n_light, n_brdf);
}
brdf_sampling_final = brdf_sampling_final/static_cast<float>(n_brdf);
color_final = brdf_sampling_final + light_sampling_final;
return color_final;
}
void tup_show_message(const char *s)
{
const char *tup = " tup ";
clear_progress();
color_set(stdout);
/* If we get to the end, show a green bar instead of grey. */
if(cur_phase == 5)
printf("[%s%s%s] ", color_final(), tup, color_end());
else
printf("[%s%.*s%s%.*s] ", color_reverse(), cur_phase, tup, color_end(), 5-cur_phase, tup+cur_phase);
timespan_end(&main_ts);
if(display_job_time)
printf("[%.3fs] ", timespan_seconds(&main_ts));
printf("%s", s);
}
glm::vec3 Integrator::EstimateDirectLighting(const Intersection &isx, unsigned int &samples_taken, const glm::vec3 &woW)
{
//for Light source sampling
//QList<glm::vec3> light_sample_pts;
glm::vec3 color_temp(0,0,0);
glm::vec3 color_final(0,0,0);
Intersection light_sample_isx; //randomly sampled intersection on the light source's surface
glm::vec3 wiW; // incoming ray in world frame
Ray light_sample_ray;
float rand1 = unif_distribution(mersenne_generator);
float rand2 = unif_distribution(mersenne_generator);
Intersection obstruction_test;
//iterate through all the light sources
for (int i = 0; i < scene->lights.count(); i++)
{
for(unsigned int j = 0; j < samples_taken; j++)
{
light_sample_isx = scene->lights[i]->GetRandISX(rand1, rand2, isx.normal); //take 1 sample point(intersection) on the light source for now
wiW = light_sample_isx.point - isx.point; //ray direction going from world point to light source
light_sample_isx.t = glm::length(wiW);
wiW = glm::normalize(wiW);
light_sample_ray = Ray(isx.point, wiW);//remember, the direction is from point in scene to light source
obstruction_test = intersection_engine->GetIntersection(light_sample_ray);
//update random point
rand1 = unif_distribution(mersenne_generator);
rand2 = unif_distribution(mersenne_generator);
if (obstruction_test.object_hit == scene->lights[i])
{
color_temp = color_temp + CalculateEnergy(light_sample_isx, isx, light_sample_ray, woW);
}
else
{
//the ray contributes zero energy
}
}
color_temp = color_temp/static_cast<float>(samples_taken); //divide by samples taken
color_final = color_final + color_temp; // accumulate energy per high source
color_temp = glm::vec3(0, 0, 0);// zero out color_temp for the next light source
}
return color_final;
}
