Added refractions and fresnel.

directional_light.cpp

@@ -13,8 +13,6 @@ vec3 DirectionalLight::shade(vec3 normal, Ray & r, Material & m) const {
   float n_dot_l, r_dot_l;
   vec3 color, ref;
 
-  //color = m.m_ambient * m_ambient;
-
   n_dot_l = max(dot(normal, m_position), 0.0);
   color += (m.m_diffuse / pi<float>()) * m_diffuse * n_dot_l;
 

directional_light.hpp

@@ -10,14 +10,12 @@ public:
     m_position = vec3(0.0f);
     m_diffuse = vec3(1.0f);
     m_specular = vec3(1.0f);
-    m_ambient = vec3(0.05f);
   }
 
-  DirectionalLight(vec3 _p, vec3 _d, vec3 _s, vec3 _a) {
+  DirectionalLight(vec3 _p, vec3 _d, vec3 _s) {
     m_position = _p;
     m_diffuse = _d;
     m_specular = _s;
-    m_ambient = _a;
   }
 
   virtual vec3 shade(vec3 normal, Ray & r, Material & m) const;

main.cpp

@@ -31,6 +31,7 @@ static vec3 ** image;
 
 static void scene_1(vector<Figure *> & vf, vector<Light *> & vl);
 static void scene_2(vector<Figure *> & vf, vector<Light *> & vl);
+static void scene_3(vector<Figure *> & vf, vector<Light *> & vl);
 
 int main(int argc, char ** argv) {
   FILE * out;
@@ -90,7 +91,7 @@ int main(int argc, char ** argv) {
     image[i] = new vec3[g_w];
   }
 
-  scene_1(figures, lights);
+  scene_3(figures, lights);
 
   tracer = Tracer(g_h, g_w, g_fov);
 
@@ -167,7 +168,6 @@ static void scene_1(vector<Figure *> & vf, vector<Light *> & vl) {
   vf.push_back(static_cast<Figure *>(s));
 
   s = new Sphere(0.0f, 0.0f, -2.0f, 1.0f);
-  //s->set_color(1.0f, 1.0f, 0.0f);
   s->m_mat.m_diffuse = vec3(1.0f, 1.0f, 0.0f);
   vf.push_back(static_cast<Figure *>(s));
 
@@ -183,6 +183,8 @@ static void scene_1(vector<Figure *> & vf, vector<Light *> & vl) {
   s = new Sphere(1.5f, 0.0f, -2.0f, 0.5f);
   s->m_mat.m_diffuse = vec3(1.0f, 1.0f, 1.0f);
   s->m_mat.m_rho = 0.08f;
+  s->m_mat.m_refract = true;
+  s->m_mat.m_ref_index = 1.1f;
   vf.push_back(static_cast<Figure *>(s));
 
   s = new Sphere(0.0f, 1.5f, -2.0f, 0.5f);
@@ -195,9 +197,11 @@ static void scene_1(vector<Figure *> & vf, vector<Light *> & vl) {
   s->m_mat.m_rho = 0.1f;
   vf.push_back(static_cast<Figure *>(s));
 
-  d = new Disk(vec3(0.0f, 2.0f, -2.0f), vec3(0.0f, -1.0f, 0.0f), 1.0f);
+  d = new Disk(vec3(-0.0f, -0.0f, -0.5f), vec3(0.0f, 0.0f, 0.1f), 0.25f);
-  d->m_mat.m_diffuse = vec3(1.0f, 1.0f, 0.0f);
+  d->m_mat.m_diffuse = vec3(1.0f, 0.0f, 0.0f);
-  d->m_mat.m_rho = 0.8f;
+  d->m_mat.m_rho = 0.3f;
+  d->m_mat.m_refract = true;
+  d->m_mat.m_ref_index = 1.33f;
   vf.push_back(static_cast<Figure *>(d));
 
   l = new DirectionalLight();
@@ -222,28 +226,28 @@ static void scene_2(vector<Figure *> & vf, vector<Light *> & vl) {
   DirectionalLight * l;
 
   p = new Plane(vec3(0.0f, -1.0f, 0.0f), vec3(0.0f, 1.0f, 0.0f));
-  //p->set_color(0.0f, 1.0f, 0.0f);
+  p->m_mat.m_diffuse = vec3(0.0f, 1.0f, 0.0f);
   vf.push_back(static_cast<Figure *>(p));
 
   p = new Plane(vec3(-1.0f, 0.0f, 0.0f), vec3(1.0f, 0.0f, 0.0f));
-  //p->set_color(1.0f, 0.0f, 0.0f);
+  p->m_mat.m_diffuse = vec3(1.0f, 0.0f, 0.0f);
   vf.push_back(static_cast<Figure *>(p));
 
   p = new Plane(vec3(1.0f, 0.0f, 0.0f), vec3(-1.0f, 0.0f, 0.0f));
-  //p->set_color(0.0f, 0.0f, 1.0f);
+  p->m_mat.m_diffuse = vec3(0.0f, 0.0f, 1.0f);
   vf.push_back(static_cast<Figure *>(p));
 
   p = new Plane(vec3(0.0f, 1.0f, 0.0f), vec3(0.0f, -1.0f, 0.0f));
-  //p->set_color(1.0f, 1.0f, 1.0f);
+  p->m_mat.m_diffuse = vec3(1.0f, 1.0f, 1.0f);
   vf.push_back(static_cast<Figure *>(p));
 
   p = new Plane(vec3(0.0f, 0.0f, -2.0f), vec3(0.0f, 0.0f, 1.0f));
-  //p->set_color(1.0f, 0.0f, 1.0f);
+  p->m_mat.m_diffuse = vec3(1.0f, 0.0f, 1.0f);
   vf.push_back(static_cast<Figure *>(p));
 
   s = new Sphere(-0.4f, -0.5f, -1.5f, 0.5f);
-  //s->set_color(1.0f, 1.0f, 0.0f);
+  s->m_mat.m_diffuse = vec3(1.0f, 1.0f, 0.0f);
-  //s->rho = 0.4f;
+  s->m_mat.m_rho = 0.4f;
   vf.push_back(static_cast<Figure *>(s));
 
   l = new DirectionalLight();
@@ -251,3 +255,35 @@ static void scene_2(vector<Figure *> & vf, vector<Light *> & vl) {
   l->m_diffuse = vec3(1.0f, 1.0f, 1.0f);
   vl.push_back(static_cast<Light *>(l));
 }
+
+static void scene_3(vector<Figure *> & vf, vector<Light *> & vl) {
+  Sphere * s;
+  Plane * p;
+  DirectionalLight * l;
+
+  s = new Sphere(0.0f, -0.15f, -2.0f, 1.0f);
+  s->m_mat.m_diffuse = vec3(1.0f, 0.5f, 0.0f);
+  s->m_mat.m_rho = 0.4f;
+  s->m_mat.m_refract = true;
+  s->m_mat.m_ref_index = 1.33f;
+  vf.push_back(static_cast<Figure *>(s));
+
+  s = new Sphere(2.0f, 0.0f, -2.0f, 1.0f);
+  s->m_mat.m_diffuse = vec3(1.0f, 0.0f, 1.0f);
+  s->m_mat.m_rho = 0.6f;
+  vf.push_back(static_cast<Figure *>(s));
+
+  s = new Sphere(-1.0f, 0.25f, -3.25f, 1.0f);
+  s->m_mat.m_diffuse = vec3(1.0f, 1.0f, 0.0f);
+  vf.push_back(static_cast<Figure *>(s));
+
+  p = new Plane(vec3(0.0f, -1.5f, 0.0f), vec3(0.0f, 1.0f, 0.0f));
+  p->m_mat.m_diffuse = vec3(1.0f, 1.0f, 1.0f);
+  p->m_mat.m_specular = vec3(0.0f);
+  vf.push_back(static_cast<Figure *>(p));
+
+  l = new DirectionalLight();
+  l->m_position = normalize(vec3(-1.0f, 1.0f, 1.0f));
+  l->m_diffuse = vec3(1.0f, 1.0f, 1.0f);
+  vl.push_back(static_cast<Light *>(l));
+}

material.hpp

@@ -10,20 +10,20 @@ class Material {
 public:
   vec3 m_diffuse;
   vec3 m_specular;
-  vec3 m_ambient;
   float m_rho;
   float m_shininess;
   float m_ref_index;
+  bool m_refract;
 
-  Material(): m_diffuse(vec3(1.0f)), m_specular(vec3(1.0f)), m_ambient(vec3(1.0f)), m_rho(0.0f), m_shininess(89.0f), m_ref_index(1.0f) { }
+  Material(): m_diffuse(vec3(1.0f)), m_specular(vec3(1.0f)), m_rho(0.0f), m_shininess(89.0f), m_ref_index(1.0f), m_refract(false) { }
 
   Material(const Material & m) {
     m_diffuse = m.m_diffuse;
     m_specular = m.m_specular;
-    m_ambient = m.m_ambient;
     m_rho = m.m_rho;
     m_shininess = m.m_shininess;
     m_ref_index = m.m_ref_index;
+    m_refract = m.m_refract;
   }
 };
 

ray.hpp

@@ -10,10 +10,13 @@ class Ray {
 public:
   vec3 m_direction;
   vec3 m_origin;
+  float m_ref_index;
 
-  Ray(): m_direction(vec3(0.0f, 0.0f, -1.0f)), m_origin(vec3(0.0f)) { }
+  Ray(): m_direction(vec3(0.0f, 0.0f, -1.0f)), m_origin(vec3(0.0f)), m_ref_index(1.0f) { }
-  Ray(float dx, float dy, float dz, float ox, float oy, float oz): m_direction(vec3(dx, dy, dz)), m_origin(vec3(ox, oy, oz)) {}
+  Ray(float dx, float dy, float dz, float ox, float oy, float oz, float _r = 1.0f): m_direction(vec3(dx, dy, dz)),
-  Ray(vec3 _d, vec3 _o): m_direction(_d), m_origin(_o) { }
+										    m_origin(vec3(ox, oy, oz)),
+										    m_ref_index(_r) { }
+  Ray(vec3 _d, vec3 _o, float _r = 1.0f): m_direction(_d), m_origin(_o), m_ref_index(_r) { }
 };
 
 #endif

tracer.cpp

@@ -1,8 +1,7 @@
+#include <iostream>
 #include <limits>
 #include <cstdlib>
 
-#include <omp.h>
-
 #include "tracer.hpp"
 
 #define MAX_RECURSION 9
@@ -15,8 +14,10 @@ using glm::normalize;
 using glm::radians;
 using glm::dot;
 using glm::reflect;
+using glm::refract;
 using glm::clamp;
 using glm::tan;
+using glm::cos;
 
 static const vec3 BCKG_COLOR = vec3(0.16f, 0.66f, 0.72f);
 
@@ -24,16 +25,30 @@ static inline float random01() {
   return static_cast<float>(rand()) / static_cast<float>(RAND_MAX);
 }
 
+static float fresnel(const vec3 & i, const vec3 & n, const float ir1, const float ir2) {
+  float cos_t1 = dot(i, n);
+  float cos_t2 = dot(normalize(refract(i, n, ir1 / ir2)), n);
+  float sin_t2 = (ir1 / ir2) * sqrt(1.0f - (cos_t2 * cos_t2));
+
+  if (sin_t2 >= 1.0f)
+    return 1.0f;
+
+  float fr_par = ((ir2 * cos_t1) - (ir1 * cos_t2)) / ((ir2 * cos_t1) + (ir1 * cos_t2));
+  float fr_per = ((ir1 * cos_t2) - (ir2 * cos_t1)) / ((ir1 * cos_t2) + (ir2 * cos_t1));
+
+  return ((fr_par * fr_par) + (fr_per * fr_per)) / 2.0f;
+}
+
 vec2 Tracer::sample_pixel(int i, int j) const {
   float pxNDC;
   float pyNDC;
   float pxS;
   float pyS;
   pyNDC = (static_cast<float>(i) + random01()) / m_h;
-  pyS = (1.0f - (2.0f * pyNDC)) * tan(radians(m_fov) / 2);
+  pyS = (1.0f - (2.0f * pyNDC)) * tan(radians(m_fov / 2));
   pxNDC = (static_cast<float>(j) + random01()) / m_w;
   pxS = (2.0f * pxNDC) - 1.0f;
-  pxS *= m_a_ratio * tan(radians(m_fov) / 2);
+  pxS *= m_a_ratio * tan(radians(m_fov / 2));
 
   return vec2(pxS, pyS);
 }
@@ -44,6 +59,7 @@ vec3 Tracer::trace_ray(Ray & r, vector<Figure *> & v_figures, vector<Light *> &
   vec3 n, color, i_pos, ref;
   Ray sr, rr;
   bool vis;
+  float kr;
 
   t = numeric_limits<float>::max();
   _f = NULL;
@@ -73,9 +89,21 @@ vec3 Tracer::trace_ray(Ray & r, vector<Figure *> & v_figures, vector<Light *> &
       color += (vis ? 1.0f : 0.0f) * v_lights[l]->shade(n, r, _f->m_mat);
     }
 
-    if (_f->m_mat.m_rho > 0.0f && rec_level < MAX_RECURSION) {
+    if (_f->m_mat.m_refract)
-      rr = Ray(reflect(r.m_direction, n), i_pos + n * BIAS);
+      kr = fresnel(r.m_direction, n, r.m_ref_index, _f->m_mat.m_ref_index);
-      color += _f->m_mat.m_rho * trace_ray(rr, v_figures, v_lights, rec_level + 1);
+    else
+      kr = _f->m_mat.m_rho;
+
+    if (kr > 0.0f && rec_level < MAX_RECURSION) {
+      rr = Ray(normalize(reflect(r.m_direction, n)), i_pos + n * BIAS);
+      color += _f->m_mat.m_rho * kr * trace_ray(rr, v_figures, v_lights, rec_level + 1);
+
+    } else if (rec_level >= MAX_RECURSION)
+      return vec3(BCKG_COLOR);
+
+    if (_f->m_mat.m_refract && kr < 1.0f && rec_level < MAX_RECURSION) {
+      rr = Ray(normalize(refract(r.m_direction, n, r.m_ref_index / _f->m_mat.m_ref_index)), i_pos - n * BIAS, _f->m_mat.m_ref_index);
+      color += (1.0f - _f->m_mat.m_rho) * (1.0f - kr) * trace_ray(rr, v_figures, v_lights, rec_level + 1);
 
     } else if (rec_level >= MAX_RECURSION)
       return vec3(BCKG_COLOR);