/**
* @brief Updates the NIKinect's Metda-Data and Image information.
* @details When called on multi-threaded environment, use it inside locks.
*
* @retval true if the information was successfully updated.
* @retval false if an error occurred.
*/
bool NIKinect::update_images(){
//Updates Depth Variables
if(this->_flags[NIKinect::DEPTH_G]){
this->_depth_generator->GetMetaData(this->_depth_md);
if(this->_flags_processing[NIKinect::DEPTH_P]){
cv::Mat depthMat16UC1(480, 640,CV_16UC1, (void*) this->_depth_md.Data());
depthMat16UC1.copyTo(this->_depth_mat);
}
if(this->_flags_processing[NIKinect::DEPTH_P]){
//cv::threshold src uses 8-bit or 32-bit floating point so you have to convert before use. Loss of performance.
//depthMat16UC1.convertTo(mask8,CV_8UC1);
//cv::threshold(mask8,this->_mask_mat,0.1,255,CV_THRESH_BINARY);
cv::inRange(this->_depth_mat,1,10000,this->_mask_mat);
}
if(this->_flags_processing[NIKinect::DEPTH_COLOR]){
double min = this->_min_depth;
double max = this->_max_depth;
NIKinect::compute_color_encoded_depth(this->_depth_mat,this->_depth_as_color_mat,&min,&max);
}
}
//Updates Image Variables
if(this->_flags[NIKinect::IMAGE_G]){
this->_image_generator->GetMetaData(_image_md);
if(this->_flags_processing[NIKinect::IMAGE_P]){
cv::Mat color_temp(_image_mode.nYRes,_image_mode.nXRes,CV_8UC3,(void*) _image_md.Data());
cv::cvtColor(color_temp,_color_mat,CV_RGB2BGR);
}
}
if(this->_flags[NIKinect::SCENE_A]){
}
if(this->_flags_processing[NIKinect::POINT_CLOUD]){
this->generate_point_cloud();
}
this->update_frame_rate();
return true;
}
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;
}
glm::vec3 AllLightingIntegrator::LightIndirectEnergy(const Intersection &isx, unsigned int n_split, const glm::vec3 &woW)
{
int depth = 0;
Intersection isx_temp = isx;//reflected intersection
Intersection isx_light; //sampled intersection with "light source"
glm::vec3 color_accum(0.0f, 0.0f, 0.0f); //accumulated color
glm::vec3 color_temp(0.0f, 0.0f, 0.0f);
glm::vec3 wi_temp(0.0f, 0.0f, 0.0f);
glm::vec3 wo_temp(woW);
glm::vec3 brdf_energy_accum(1.0f, 1.0f, 1.0f);
glm::vec3 brdf_energy_temp(0.0f, 0.0f, 0.0f);
glm::vec3 L_temp(0.0f, 0.0f, 0.0f);
Material* M_temp = isx.object_hit->material;
Geometry* obj_temp; //stores the temporary sampled object
Ray sampler;
float pdf_temp_brdf(0);
float pdf_light_temp(0);
float W(0); //for MIS
float rand1 = unif_distribution(mersenne_generator);
float rand2 = unif_distribution(mersenne_generator);
float epsilon = 0.0001f;
float throughput = 1.000001f;
float russian = unif_distribution(mersenne_generator);
//default samples for direct lighting when estimating the irradiance of some other point in the scene
unsigned int n_light = 10;
unsigned int n_brdf = 10;
int light_source_choice(0);
while(depth < max_depth && (russian < throughput || depth < 2))
{
//sample a random point on a random object in the scene
light_source_choice = rand()%scene->objects.count();
obj_temp = scene->objects[light_source_choice];
//if I hit a real light source, kill the ray
if (scene->objects[light_source_choice]->material->is_light_source) break;
isx_light = obj_temp->GetRandISX(rand1, rand2, isx_temp.normal);
//update random numbers
rand1 = unif_distribution(mersenne_generator);
rand2 = unif_distribution(mersenne_generator);
//make ray towards these points
wi_temp = glm::normalize(isx_light.point - isx_temp.point);
sampler = Ray(isx_temp.point, wi_temp);
//update my light intersection
isx_light = intersection_engine->GetIntersection(sampler);
//this ray dies if it hit nothing or is blocked, kill the ray as well
if(isx_light.object_hit == NULL) break;
if(isx_light.object_hit != obj_temp) break;
//to avoid shadow acne
isx_light.point = isx_light.point + epsilon*isx_light.normal;
//find out the pdf w/r/t light
pdf_light_temp = obj_temp->RayPDF(isx_light, sampler);
//if my pdf is negative, kill the ray as well
if(pdf_light_temp <= 0) break;
//update accumulated brdf energy
brdf_energy_temp = M_temp->EvaluateScatteredEnergy(isx_temp, wo_temp, wi_temp, pdf_temp_brdf);
brdf_energy_accum = ComponentMult(brdf_energy_accum, brdf_energy_temp);
//find the direct lighting irradiance of this point towards my original intersection
wo_temp = -wi_temp; //now the old incoming ray is the outgoing ray for the new intersection
L_temp = EstimateDirectLighting(isx_light, n_light, n_brdf, wo_temp);
W = MIS(pdf_light_temp, pdf_temp_brdf);
//this is light source sampling so use the illumination equation for BRDF sampling to accumulate color
color_temp = ComponentMult(brdf_energy_accum, L_temp);
color_temp = ComponentMult(ComponentMult(color_temp, M_temp->base_color), isx_temp.texture_color);
color_temp = color_temp*W/pdf_light_temp*glm::abs(glm::dot(isx_temp.normal, wi_temp));
color_accum = color_accum + color_temp/static_cast<float>(n_split);
throughput = throughput * glm::max(glm::max(color_accum.r, color_accum.g), color_accum.b);
//update the temporary material
M_temp = isx_light.object_hit->material;
isx_temp = isx_light;
//update random number
//update depth
depth++;
russian = unif_distribution(mersenne_generator);
}
return color_accum;
}
glm::vec3 AllLightingIntegrator::BxDFIndirectEnergy(const Intersection &isx, unsigned int n_split, const glm::vec3 &woW)
{
int depth = 0;
Intersection isx_temp = isx;//reflected intersection
Intersection isx_light; //sampled intersection with "light source"
glm::vec3 color_accum(0.0f, 0.0f, 0.0f); //accumulated color
glm::vec3 color_temp(0.0f, 0.0f, 0.0f);
glm::vec3 wi_temp(0.0f, 0.0f, 0.0f);
glm::vec3 wo_temp(woW);
glm::vec3 brdf_energy_accum(1.0f, 1.0f, 1.0f);
glm::vec3 brdf_energy_temp(0.0f, 0.0f, 0.0f);
glm::vec3 L_temp(0.0f, 0.0f, 0.0f);
Material* M_temp = isx.object_hit->material;
Ray sampler;
float pdf_temp_brdf(0);
float pdf_light_temp(0);
float W(0); //for MIS
float rand1 = unif_distribution(mersenne_generator);
float rand2 = unif_distribution(mersenne_generator);
float epsilon = 0.0001;
float throughput = 1.000001f;
float russian = unif_distribution(mersenne_generator);
//default samples for direct lighting when estimating the irradiance of some other point in the scene
unsigned int n_light = 10;
unsigned int n_brdf = 10;
while(depth < max_depth && (russian < throughput || depth < 2))
{
//sample random brdf starting at the input isx direction to get reflected ray to begin
brdf_energy_temp = M_temp->SampleAndEvaluateScatteredEnergy(isx_temp, wo_temp, wi_temp, pdf_temp_brdf, rand1, rand2);
//update accumulated brdf energy
brdf_energy_accum = ComponentMult(brdf_energy_accum, brdf_energy_temp);
//use the sampled incoming ray to find a reflected intersection
sampler = Ray(isx_temp.point, wi_temp);
isx_light = intersection_engine->GetIntersection(sampler);
//this ray dies if I hit a real light source or nothing
if(isx_light.object_hit == NULL) break;
else if(isx_light.object_hit->material->is_light_source) break;
//
//to avoid shadow acne
isx_light.point = isx_light.point + epsilon*isx_light.normal;
//find the direct lighting irradiance of this point towards my original intersection
wo_temp = -wi_temp; //now the old incoming ray is the outgoing ray for the new intersection
L_temp = EstimateDirectLighting(isx_light, n_light, n_brdf, wo_temp); //the direct lighting towards the isx
pdf_light_temp = isx_light.object_hit->RayPDF(isx_light, sampler);
W = MIS(pdf_temp_brdf, pdf_light_temp);
//this is BRDF sampling so use the illumination equation for BRDF sampling to accumulate color
color_temp = ComponentMult(brdf_energy_accum, L_temp);
color_temp = ComponentMult(ComponentMult(color_temp, M_temp->base_color), isx_temp.texture_color);
color_temp = color_temp*W/pdf_temp_brdf*glm::abs(glm::dot(isx_temp.normal, wi_temp));
color_accum = color_accum + color_temp/static_cast<float>(n_split);
throughput = throughput * glm::max(glm::max(color_accum.r, color_accum.g), color_accum.b);
//update the temporary material
M_temp = isx_light.object_hit->material;
isx_temp = isx_light;
//update random number
rand1 = unif_distribution(mersenne_generator);
rand2 = unif_distribution(mersenne_generator);
//update depth
depth++;
russian = unif_distribution(mersenne_generator);
}
return color_accum;
}
