Code clean up and refactoring.

.gitignore

@@ -28,3 +28,6 @@
 *.out
 *.app
 ray
+
+# Emacs droppings
+*~

Makefile

@@ -1,6 +1,6 @@
 TARGET = ray
-HEADERS = ray.hpp sphere.hpp figure.hpp
-OBJECTS = main.o sphere.o
+HEADERS = ray.hpp sphere.hpp figure.hpp light.hpp tracer.hpp
+OBJECTS = main.o sphere.o tracer.o
 CXX = g++
 CXXFLAGS = -ansi -pedantic -Wall -g -DGLM_FORCE_RADIANS -fopenmp
 LDLIBS = -lm
@@ -15,6 +15,8 @@ main.o: main.cpp $(HEADERS)
 
 sphere.o: sphere.cpp $(HEADERS)
 
+tracer.o: tracer.cpp $(HEADERS)
+
 .PHONY: clean
 clean:
-	$(RM) $(TARGET) *.o
+	$(RM) $(TARGET) $(OBJECTS)

figure.hpp

@@ -6,13 +6,15 @@
 
 #include "ray.hpp"
 
+using glm::vec3;
+
 class Figure {
 public:
   vec3 color;
 
   virtual ~Figure() { }
 
-  virtual bool intersect(Ray & r, float & t) const = 0;
+  virtual bool intersect(Ray & r, float & t, vec3 & n) const = 0;
 
   virtual void set_color(float r, float g, float b) {
     color = vec3(r, g, b);

light.hpp

@@ -0,0 +1,18 @@
+#pragma once
+#ifndef LIGHT_HPP
+#define LIGHT_HPP
+
+#include <glm/vec3.hpp>
+
+class Light {
+public:
+  vec3 position;
+  vec3 diffuse;
+  vec3 specular;
+  vec3 ambient;
+
+  Light(): position(vec3(0.0f)), diffuse(vec3(1.0f)), specular(vec3(1.0f)), ambient(vec3(0.1f)) { }
+  Light(vec3 _p, vec3 _d, vec3 _s, vec3 _a): position(_p), diffuse(_d), specular(_s), ambient(_a) { }
+};
+
+#endif

main.cpp

@@ -1,10 +1,8 @@
 #include <iostream>
 #include <vector>
-#include <limits>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
-#include <cmath>
 
 #include <omp.h>
 #include <glm/glm.hpp>
@@ -12,11 +10,14 @@
 #include "ray.hpp"
 #include "figure.hpp"
 #include "sphere.hpp"
+#include "light.hpp"
+#include "tracer.hpp"
 
 using namespace std;
 using namespace glm;
 
-static const vec3 BCKG_COLOR = vec3(0.16f, 0.66f, 0.72f);
+#define MAX_RECURSION 9
+
 static const char * OUT_FILE = "output.ppm";
 
 static char * input_file;
@@ -24,21 +25,17 @@ static int g_samples = 25;
 static float g_fov = 90.0f;
 static int g_w = 640;
 static int g_h = 480;
-static float g_aspect_ratio = static_cast<float>(g_w) / g_h;
 static vec3 ** image;
 
-float random01();
-vec2 sample_pixel(int i, int j);
-
 int main(int argc, char ** argv) {
   FILE * out;
-  float t;
-  float _t;
   Sphere * s;
-  Figure * _f;
+  Light * l;
   Ray r;
   vec2 sample;
   vector<Figure *> figures;
+  vector<Light *> lights;
+  Tracer tracer;
 
   if(argc < 2 || argc == 3 || argc > 6) {
     cerr << "USAGE: " << argv[0] << " IN FILE [OUT FILE [HEIGHT WIDTH [SAMPLES [FIELD OF VIEW]]]]" << endl;
@@ -108,38 +105,34 @@ int main(int argc, char ** argv) {
   s->set_color(1.0f, 1.0f, 0.0f);
   figures.push_back(static_cast<Figure *>(s));
 
-#pragma omp parallel for schedule(dynamic, 1) private(r, sample, _f, t, _t)
+  l = new Light();
+  lights.push_back(l);
+
+  tracer = Tracer(g_h, g_w, g_fov);
+
+#pragma omp parallel for schedule(dynamic, 1) private(r, sample)
   for (int i = 0; i < g_h; i++) {
     for (int j = 0; j < g_w; j++) {
       for (int k = 0; k < g_samples; k++) {
-	sample = sample_pixel(i, j);
+	sample = tracer.sample_pixel(i, j);
 	r = Ray(normalize(vec3(sample, -1.0f) - vec3(0.0f, 0.0f, 0.0f)), vec3(0.0f, 0.0f, 0.0f));
-	t = numeric_limits<float>::max();
-	_f = NULL;
-
-	for (size_t f = 0; f < figures.size(); f++) {
-	  if (figures[f]->intersect(r, _t) && _t < t) {
-	    t = _t;
-	    _f = figures[f];
-	  }
-	}
-
-	if (_f != NULL) {
-	  image[i][j] += vec3(_f->color);
-	} else {
-	  image[i][j] += vec3(BCKG_COLOR);
-	}
+	image[i][j] += tracer.trace_ray(r, figures, lights, MAX_RECURSION);
       }
 
       image[i][j] /= g_samples;
     }
   }
 
-  for (size_t f = 0; f < figures.size(); f++) {
-    delete static_cast<Sphere *>(figures[f]);
+  for (size_t i = 0; i < figures.size(); i++) {
+    delete static_cast<Sphere *>(figures[i]);
   }
   figures.clear();
 
+  for (size_t i = 0; i < figures.size(); i++) {
+    delete lights[i];
+  }
+  lights.clear();
+
   fprintf(out, "P6 %d %d %d ", g_w, g_h, 255);
   for (int i = 0; i < g_h; i++) {
     for (int j = 0; j < g_w; j++) {
@@ -156,21 +149,3 @@ int main(int argc, char ** argv) {
 
   return EXIT_SUCCESS;
 }
-
-inline float random01() {
-  return static_cast<float>(rand()) / static_cast<float>(RAND_MAX);
-}
-
-vec2 sample_pixel(int i, int j) {
-  float pxNDC;
-  float pyNDC;
-  float pxS;
-  float pyS;
-  pyNDC = (static_cast<float>(i) + random01()) / g_h;
-  pyS = (1.0f - (2.0f * pyNDC)) * tan(radians(g_fov) / 2);
-  pxNDC = (static_cast<float>(j) + random01()) / g_w;
-  pxS = (2.0f * pxNDC) - 1.0f;
-  pxS *= g_aspect_ratio * tan(radians(g_fov) / 2);
-
-  return vec2(pxS, pyS);
-}

sphere.cpp

@@ -2,7 +2,10 @@
 
 #include "sphere.hpp"
 
-bool Sphere::intersect(Ray & r, float & t) const {
+using glm::normalize;
+
+bool Sphere::intersect(Ray & r, float & t, vec3 & n) const {
+  vec3 i;
   float d;
 
   float a = (r.m_direction.x * r.m_direction.x) +
@@ -23,7 +26,11 @@ bool Sphere::intersect(Ray & r, float & t) const {
 
   d = (b * b) - (4 * a * c);
 
+  if (d >= 0.0f) {
     t = (-b - sqrt(d)) / (2 * a);
+    i = vec3(r.m_origin + (t * r.m_direction));
+    n = normalize(vec3((i - m_center) / m_radius));
+  }
 
   return d >= 0.0f;
 }

sphere.hpp

@@ -2,7 +2,7 @@
 #ifndef SPHERE_HPP
 #define SPHERE_HPP
 
-#include <glm/vec3.hpp>
+#include <glm/glm.hpp>
 
 #include "figure.hpp"
 
@@ -21,7 +21,7 @@ public:
 
   virtual ~Sphere() { }
 
-  virtual bool intersect(Ray & r, float & t) const;
+  virtual bool intersect(Ray & r, float & t, vec3 & n) const;
 };
 
 #endif

tracer.cpp

@@ -0,0 +1,57 @@
+#include <limits>
+#include <cstdlib>
+#include <cmath>
+
+#include <omp.h>
+
+#include "tracer.hpp"
+
+using namespace std;
+
+static const vec3 BCKG_COLOR = vec3(0.16f, 0.66f, 0.72f);
+
+static inline float random01() {
+  return static_cast<float>(rand()) / static_cast<float>(RAND_MAX);
+}
+
+Tracer::Tracer(): m_h(640), m_w(480), m_fov(90.0f), m_a_ratio(640.0f / 480.0f) {}
+
+Tracer::Tracer(int h, int w, float fov): m_h(h), m_w(w), m_fov(fov) {
+  m_a_ratio = static_cast<float>(w) / h;
+}
+
+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);
+  pxNDC = (static_cast<float>(j) + random01()) / m_w;
+  pxS = (2.0f * pxNDC) - 1.0f;
+  pxS *= m_a_ratio * tan(radians(m_fov) / 2);
+
+  return vec2(pxS, pyS);
+}
+
+vec3 Tracer::trace_ray(Ray & r, vector<Figure *> & vf, vector<Light *> & vl, unsigned int rec_level) const {
+  float t;
+  float _t;
+  Figure * _f;
+  vec3 n;
+
+  t = numeric_limits<float>::max();
+  _f = NULL;
+  
+  for (size_t f = 0; f < vf.size(); f++) {
+    if (vf[f]->intersect(r, _t, n) && _t < t) {
+      t = _t;
+      _f = vf[f];
+    }
+  }
+  
+  if (_f != NULL)
+    return _f->color;
+  else
+    return vec3(BCKG_COLOR);
+}

tracer.hpp

@@ -0,0 +1,32 @@
+#pragma once
+#ifndef TRACER_HPP
+#define TRACER_HPP
+
+#include <vector>
+
+#include <glm/glm.hpp>
+
+#include "figure.hpp"
+#include "light.hpp"
+#include "ray.hpp"
+
+using std::vector;
+using glm::radians;
+using glm::vec3;
+using glm::vec2;
+
+class Tracer {
+public:
+  int m_h;
+  int m_w;
+  float m_fov;
+  float m_a_ratio;
+
+  Tracer();
+  Tracer(int w, int h, float fov);
+
+  vec2 sample_pixel(int i, int j) const;
+  vec3 trace_ray(Ray & r, vector<Figure *> & f, vector<Light *> & l, unsigned int rec_level) const;
+};
+
+#endif