Added camera abstraction.

Makefile

@@ -1,6 +1,6 @@
 CXX = g++
 TARGET = ray
-OBJECTS = main.o disk.o plane.o sphere.o directional_light.o phong_brdf.o point_light.o spot_light.o tracer.o path_tracer.o whitted_tracer.o
+OBJECTS = main.o sampling.o camera.o disk.o plane.o sphere.o directional_light.o phong_brdf.o point_light.o spot_light.o tracer.o path_tracer.o whitted_tracer.o
 DEPENDS = $(OBJECTS:.o=.d)
 CXXFLAGS = -ansi -pedantic -Wall -DGLM_FORCE_RADIANS -fopenmp
 LDLIBS = -lfreeimage

camera.cpp

@@ -0,0 +1,64 @@
+#include <glm/gtx/rotate_vector.hpp>
+
+#include "camera.hpp"
+#include "sampling.hpp"
+
+using glm::vec4;
+using glm::rotate;
+using glm::radians;
+using glm::cross;
+
+void Camera::reset() {
+  m_inv_view_matrix = inverse(lookAt(m_eye, m_look, m_up));
+}
+
+void Camera::translate(vec3 t) {
+  mat4 t_matrix = glm::translate(mat4(1.0f), t);
+  vec4 new_eye = t_matrix * vec4(m_eye, 1.0f);
+  vec4 new_look = t_matrix * vec4(m_look, 1.0f);
+  m_eye = vec3(new_eye.x, new_eye.y, new_eye.z);
+  m_look = vec3(new_look.x, new_look.y, new_look.z);
+  reset();
+}
+
+void Camera::pitch(float angle) {
+  vec3 view_dir = normalize(m_look - m_eye);
+  vec3 left = cross(view_dir, m_up);
+  view_dir = rotate(view_dir, radians(angle), left);
+  m_up = normalize(rotate(m_up, radians(angle), left));
+  m_look = m_eye + view_dir;
+  reset();
+}
+
+void Camera::yaw(float angle) {
+  vec3 view_dir = rotate(normalize(m_look - m_eye), radians(angle), m_up);
+  m_look = m_eye + view_dir;
+  reset();
+}
+
+void Camera::roll(float angle) {
+  m_up = normalize(rotate(m_up, radians(angle), normalize(m_look - m_eye)));
+  reset();
+}
+
+void Camera::view_to_world(Ray & r) const {
+  vec4 dir = m_inv_view_matrix * vec4(r.m_direction, 0.0f);
+  vec4 orig = m_inv_view_matrix * vec4(r.m_origin, 1.0f);
+
+  r.m_direction = vec3(dir.x, dir.y, dir.z);
+  r.m_origin = vec3(orig.x, orig.y, orig.z);
+}
+
+vec2 Camera::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)) * glm::tan(radians(m_fov / 2.0f));
+  pxNDC = (static_cast<float>(j) + random01()) / m_w;
+  pxS = (2.0f * pxNDC) - 1.0f;
+  pxS *= m_a_ratio * glm::tan(radians(m_fov / 2.0f));
+
+  return vec2(pxS, pyS);
+}

camera.hpp

@@ -0,0 +1,51 @@
+#pragma once
+#ifndef CAMERA_HPP
+#define CAMERA_HPP
+
+#include <glm/glm.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+
+#include "ray.hpp"
+
+using glm::mat4;
+using glm::vec2;
+using glm::vec3;
+using glm::normalize;
+using glm::lookAt;
+using glm::inverse;
+
+class Camera {
+public:
+  int m_h;
+  int m_w;
+  float m_fov;
+  float m_a_ratio;
+  vec3 m_eye;
+  vec3 m_look;
+  vec3 m_up;
+
+  Camera(int h = 480, int w = 640, float fov = 90.0f, vec3 _e = vec3(0.0f), vec3 _l = vec3(0.0f, 0.0f, -1.0f), vec3 _u = vec3(0.0f, 1.0f, 0.0f)):
+    m_h(h),
+    m_w(w),
+    m_fov(fov),
+    m_eye(_e),
+    m_look(_l),
+    m_up(normalize(_u))
+  {
+    m_a_ratio = static_cast<float>(w) / static_cast<float>(h);
+    m_inv_view_matrix = inverse(lookAt(_e, _l, _u));
+  }
+
+  void reset();
+  void translate(vec3 t);
+  void pitch(float angle);
+  void yaw(float angle);
+  void roll(float angle);
+  vec2 sample_pixel(int i, int j) const;
+  void view_to_world(Ray & r) const;
+
+private:
+  mat4 m_inv_view_matrix;
+};
+
+#endif

main.cpp

@@ -11,6 +11,7 @@
 #include <glm/gtc/matrix_transform.hpp>
 #include <FreeImage.h>
 
+#include "camera.hpp"
 #include "ray.hpp"
 #include "figure.hpp"
 #include "sphere.hpp"
@@ -32,10 +33,10 @@ using namespace glm;
 ////////////////////////////////////////////
 // Function prototypes.
 ////////////////////////////////////////////
-static void scene_1(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view);
-static void scene_2(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view);
-static void scene_3(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view);
-static void scene_4(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view);
+static void scene_1(vector<Figure *> & vf, vector<Light *> & vl, Camera * c);
+static void scene_2(vector<Figure *> & vf, vector<Light *> & vl, Camera * c);
+static void scene_3(vector<Figure *> & vf, vector<Light *> & vl, Camera * c);
+static void scene_4(vector<Figure *> & vf, vector<Light *> & vl, Camera * c);
 static void print_usage(char ** const argv);
 static void parse_args(int argc, char ** const argv);
 
@@ -70,30 +71,31 @@ int main(int argc, char ** argv) {
   Tracer * tracer;
   size_t total;
   size_t current = 0;
-  mat4x4 i_model_view;
-  vec4 dir, orig;
   FIBITMAP * output_bitmap;
   FREE_IMAGE_FORMAT fif;
   BYTE * bits;
   int bpp;
+  Camera  * cam;
 
   parse_args(argc, argv);
   
   // Initialize everything.
   FreeImage_Initialise();
 
+  cam = new Camera(g_h, g_w, g_fov);
+  
   image = new vec3*[g_h];
   for (int i = 0; i < g_h; i++) {
     image[i] = new vec3[g_w];
   }
   
-  scene_2(figures, lights, i_model_view);
+  scene_2(figures, lights, cam);
 
   // Create the tracer object.
   if (g_tracer == WHITTED)
-    tracer = static_cast<Tracer *>(new WhittedTracer(g_h, g_w, g_fov, g_max_depth));
+    tracer = static_cast<Tracer *>(new WhittedTracer(g_max_depth));
   else if(g_tracer == MONTE_CARLO)
-    tracer = static_cast<Tracer *>(new PathTracer(g_h, g_w, g_fov, g_max_depth));
+    tracer = static_cast<Tracer *>(new PathTracer(g_max_depth));
   else if(g_tracer == JENSEN) {
     cerr << "Photon mapping coming soon." << endl;
     return EXIT_FAILURE;
@@ -105,14 +107,13 @@ int main(int argc, char ** argv) {
   
   // Generate the image.
   total = g_h * g_w * g_samples;
-#pragma omp parallel for schedule(dynamic, 1) private(r, sample, dir, orig) shared(current)
+#pragma omp parallel for schedule(dynamic, 1) private(r, sample) shared(current)
   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 = tracer->sample_pixel(i, j);
-	dir = i_model_view * normalize(vec4(sample, -0.5f, 1.0f) - vec4(0.0f, 0.0f, 0.0f, 1.0f));
-	orig = i_model_view * vec4(0.0f, 0.0f, 0.0f, 1.0f);
-	r = Ray(dir.x, dir.y, dir.z, orig.x, orig.y, orig.z);
+	sample = cam->sample_pixel(i, j);
+	r = Ray(normalize(vec3(sample, -0.5f) - vec3(0.0f)), vec3(0.0f));
+	cam->view_to_world(r);
 	image[i][j] += tracer->trace_ray(r, figures, lights, 0);
 #pragma omp atomic
 	current++;
@@ -146,6 +147,7 @@ int main(int argc, char ** argv) {
   if (g_out_file_name != NULL)
     free(g_out_file_name);
 
+  delete cam;
   delete tracer;
 
   for (size_t i = 0; i < figures.size(); i++) {
@@ -292,7 +294,7 @@ void parse_args(int argc, char ** const argv) {
   g_input_file = argv[optind];
 }
 
-void scene_1(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view) {
+void scene_1(vector<Figure *> & vf, vector<Light *> & vl, Camera * c) {
   Sphere * s;
   Plane * p;
   Disk * d;
@@ -367,7 +369,7 @@ void scene_1(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view)
   vl.push_back(static_cast<Light *>(l));
 }
 
-void scene_2(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view) {
+void scene_2(vector<Figure *> & vf, vector<Light *> & vl, Camera * c) {
   Sphere * s;
   Plane * p;
   Disk * d;
@@ -435,14 +437,19 @@ void scene_2(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view)
   vl.push_back(static_cast<Light *>(l));
 }
 
-void scene_3(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view) {
+void scene_3(vector<Figure *> & vf, vector<Light *> & vl, Camera * c) {
   Sphere * s;
   Plane * p;
   DirectionalLight * l;
   vec3 eye = vec3(0.0f, 1.5f, 0.0f);
   vec3 center = vec3(0.0f, 0.0f, -2.0f);
   vec3 left = vec3(-1.0f, 0.0f, 0.0f);
-  vec3 up = cross(center - eye, left);
+
+  c->m_eye = eye;
+  c->m_look = center;
+  c->m_up = cross(normalize(center - eye), left);
+  c->translate(vec3(1.0f, 0.0f, 0.0f));
+  c->roll(15.0f);
 
   s = new Sphere(0.0f, -0.15f, -2.0f, 1.0f);
   s->m_mat->m_diffuse = vec3(1.0f, 0.5f, 0.0f);
@@ -498,11 +505,9 @@ void scene_3(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view)
   l->m_position = normalize(vec3(1.0f, 0.0f, 1.0f));
   l->m_diffuse = vec3(0.5f);
   vl.push_back(static_cast<Light *>(l));
-
-  i_model_view = inverse(lookAt(eye, center, up));
 }
 
-void scene_4(vector<Figure *> & vf, vector<Light *> & vl, mat4x4 & i_model_view) {
+void scene_4(vector<Figure *> & vf, vector<Light *> & vl, Camera * c) {
   Sphere * s;
   Plane * p;
 

path_tracer.cpp

@@ -3,14 +3,13 @@
 #include <glm/gtc/constants.hpp>
 
 #include "path_tracer.hpp"
+#include "sampling.hpp"
 
 using std::numeric_limits;
 using namespace glm;
 
 PathTracer::~PathTracer() { }
 
-static const float PDF = (1.0f / (2.0f * pi<float>()));
-
 vec3 PathTracer::trace_ray(Ray & r, vector<Figure *> & v_figures, vector<Light *> & v_lights, unsigned int rec_level) const {
   float t, _t;
   Figure * _f;
@@ -121,5 +120,5 @@ vec3 PathTracer::trace_ray(Ray & r, vector<Figure *> & v_figures, vector<Light *
     return clamp(color, 0.0f, 1.0f);
 
   } else
-    return /*vec3(0.0f)*/ BCKG_COLOR;
+    return BCKG_COLOR;
 }

path_tracer.hpp

@@ -8,7 +8,7 @@ class PathTracer: public Tracer {
 public:
   PathTracer(): Tracer() { }
 
-  PathTracer(int h, int w, float fov, unsigned int max_depth): Tracer(h, w, fov, max_depth) { };
+  PathTracer(unsigned int max_depth): Tracer(max_depth) { };
 
   virtual ~PathTracer();
 

sampling.cpp

@@ -0,0 +1,45 @@
+#include <cstdlib>
+
+#include <glm/glm.hpp>
+#include <glm/gtc/constants.hpp>
+
+#include "sampling.hpp"
+
+using glm::mat3;
+using glm::abs;
+using glm::normalize;
+using glm::cross;
+using glm::pi;
+
+const float PDF = (1.0f / (2.0f * pi<float>()));
+
+float random01() {
+  return static_cast<float>(rand()) / static_cast<float>(RAND_MAX);
+}
+
+/* Sampling functions pretty much taken from scratchapixel.com */
+void create_coords_system(const vec3 &n, vec3 &nt, vec3 &nb) {
+  if (abs(n.x) > abs(n.y))
+    nt = normalize(vec3(n.z, 0.0f, -n.x));
+  else
+    nt = normalize(vec3(0.0f, -n.z, n.y));
+  nb = normalize(cross(n, nt));
+}
+
+vec3 sample_hemisphere(const float r1, float r2) {
+  float sin_t = glm::sqrt(1.0f - (r1 * r1));
+  float phi = 2 * pi<float>() * r2;
+  float x = sin_t * glm::cos(phi);
+  float z = sin_t * glm::sin(phi);
+  return vec3(x, r1, z);
+}
+
+void rotate_sample(vec3 & sample, vec3 & n) {
+  vec3 nt, nb;
+  mat3 rot_m;
+
+  create_coords_system(n, nt, nb);
+  sample = vec3(sample.x * nb.x + sample.y * n.x + sample.z * nt.x,
+		sample.x * nb.y + sample.y * n.y + sample.z * nt.y,
+		sample.x * nb.z + sample.y * n.z + sample.z * nt.z);
+}

sampling.hpp

@@ -0,0 +1,16 @@
+#pragma once
+#ifndef SAMPLING_HPP
+#define SAMPLING_HPP
+
+#include <glm/vec3.hpp>
+
+using glm::vec3;
+
+extern const float PDF;
+
+extern float random01();
+extern void create_coords_system(const vec3 &n, vec3 &nt, vec3 &nb);
+extern vec3 sample_hemisphere(const float r1, float r2);
+extern void rotate_sample(vec3 & sample, vec3 & n);
+
+#endif

tracer.cpp

@@ -1,23 +1,17 @@
-#include <cstdlib>
-
-#include <glm/gtc/constants.hpp>
-
 #include "tracer.hpp"
 
-using namespace glm;
+using glm::dot;
+using glm::normalize;
+using glm::refract;
 
 const float BIAS = 0.000001f;
 
 const vec3 BCKG_COLOR = vec3(1.0f);
 
-float Tracer::random01() const {
-  return static_cast<float>(rand()) / static_cast<float>(RAND_MAX);
-}
-
 float Tracer::fresnel(const vec3 & i, const vec3 & n, const float ir1, const float ir2) const {
   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));
+  float sin_t2 = (ir1 / ir2) * glm::sqrt(1.0f - (cos_t2 * cos_t2));
 
   if (sin_t2 >= 1.0f)
     return 1.0f;
@@ -27,44 +21,3 @@ float Tracer::fresnel(const vec3 & i, const vec3 & n, const float ir1, const flo
 
   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));
-  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);
-}
-
-/* Helper functions pretty much taken from scratchapixel.com */
-void Tracer::create_coords_system(const vec3 &n, vec3 &nt, vec3 &nb) const {
-  if (abs(n.x) > abs(n.y))
-    nt = normalize(vec3(n.z, 0.0f, -n.x));
-  else
-    nt = normalize(vec3(0.0f, -n.z, n.y));
-  nb = normalize(cross(n, nt));
-}
-
-vec3 Tracer::sample_hemisphere(const float r1, const float r2) const {
-  float sin_t = sqrt(1.0f - (r1 * r1));
-  float phi = 2 * pi<float>() * r2;
-  float x = sin_t * cos(phi);
-  float z = sin_t * sin(phi);
-  return vec3(x, r1, z);
-}
-
-void Tracer::rotate_sample(vec3 & sample, const vec3 & n) const {
-  vec3 nt, nb;
-  mat3 rot_m;
-
-  create_coords_system(n, nt, nb);
-  sample = vec3(sample.x * nb.x + sample.y * n.x + sample.z * nt.x,
-		sample.x * nb.y + sample.y * n.y + sample.z * nt.y,
-		sample.x * nb.z + sample.y * n.z + sample.z * nt.z);
-}

tracer.hpp

@@ -20,29 +20,18 @@ extern const vec3 BCKG_COLOR;
 
 class Tracer {
 public:
-  int m_h;
-  int m_w;
-  float m_fov;
-  float m_a_ratio;
   unsigned int m_max_depth;
 
-  Tracer(): m_h(480), m_w(640), m_fov(90.0f), m_a_ratio(640.0f / 480.0f), m_max_depth(5) { }
+  Tracer(): m_max_depth(5) { }
 
-  Tracer(int h, int w, float fov, unsigned int max_depth): m_h(h), m_w(w), m_fov(fov), m_max_depth(max_depth) {
-    m_a_ratio = static_cast<float>(w) / static_cast<float>(h);
-  };
+  Tracer(unsigned int max_depth): m_max_depth(max_depth) { }
 
   virtual ~Tracer() { }
 
-  vec2 sample_pixel(int i, int j) const;
   virtual vec3 trace_ray(Ray & r, vector<Figure *> & v_figures, vector<Light *> & v_lights, unsigned int rec_level) const = 0;
 
 protected:
-  float random01() const;
   float fresnel(const vec3 & i, const vec3 & n, const float ir1, const float ir2) const;
-  void create_coords_system(const vec3 &n, vec3 &nt, vec3 &nb) const;
-  vec3 sample_hemisphere(const float r1, const float r2) const;
-  void rotate_sample(vec3 & sample, const vec3 & n) const;
 };
 
 #endif

whitted_tracer.hpp

@@ -8,7 +8,7 @@ class WhittedTracer: public Tracer {
 public:
   WhittedTracer(): Tracer() { }
 
-  WhittedTracer(int h, int w, float fov, unsigned int max_depth): Tracer(h, w, fov, max_depth) { };
+  WhittedTracer(unsigned int max_depth): Tracer(max_depth) { };
 
   virtual ~WhittedTracer();