Added ray-plane intersection.

Makefile

@@ -1,6 +1,6 @@
 TARGET = ray
-HEADERS = ray.hpp sphere.hpp figure.hpp light.hpp tracer.hpp
-OBJECTS = main.o sphere.o tracer.o
+HEADERS = ray.hpp figure.hpp sphere.hpp plane.hpp light.hpp tracer.hpp
+OBJECTS = main.o sphere.o plane.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)
 
+plane.o: plane.cpp $(HEADERS)
+
 tracer.o: tracer.cpp $(HEADERS)
 
 .PHONY: clean

main.cpp

@@ -10,6 +10,7 @@
 #include "ray.hpp"
 #include "figure.hpp"
 #include "sphere.hpp"
+#include "plane.hpp"
 #include "light.hpp"
 #include "tracer.hpp"
 
@@ -30,6 +31,7 @@ static vec3 ** image;
 int main(int argc, char ** argv) {
   FILE * out;
   Sphere * s;
+  Plane * p;
   Light * l;
   Ray r;
   vec2 sample;
@@ -98,13 +100,17 @@ int main(int argc, char ** argv) {
   figures.push_back(static_cast<Figure *>(s));
 
   s = new Sphere(-1.0f, -1.0f, -2.0f, 0.5f);
-  s->set_color(0.5f, 0.5f, 0.5f);
+  s->set_color(1.0f, 0.0f, 1.0f);
   figures.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);
   figures.push_back(static_cast<Figure *>(s));
 
+  p = new Plane(vec3(0.0f, -1.0f, 0.0f), vec3(0.0f, 1.0f, 0.0f));
+  p->set_color(0.0f, 1.0f, 1.0f);
+  figures.push_back(static_cast<Figure *>(p));
+
   l = new Light();
   lights.push_back(l);
 
@@ -124,7 +130,7 @@ int main(int argc, char ** argv) {
   }
 
   for (size_t i = 0; i < figures.size(); i++) {
-    delete static_cast<Sphere *>(figures[i]);
+    delete figures[i];
   }
   figures.clear();
 

plane.cpp

@@ -0,0 +1,20 @@
+#include <cmath>
+
+#include "plane.hpp"
+
+#define TOL 1e-6
+
+using std::abs;
+using glm::dot;
+
+bool Plane::intersect(Ray & r, float & t, vec3 & n) const {
+  float d = dot(r.m_direction, m_normal);
+
+  if (abs(d) > TOL) {
+    t = dot(m_normal, (m_point - r.m_origin)) / d;
+    n = vec3(m_normal);
+    return t >= 0.0f;
+  }
+
+   return false;
+}

plane.hpp

@@ -0,0 +1,29 @@
+#pragma once
+#ifndef PLANE_HPP
+#define PLANE_HPP
+
+#include <glm/glm.hpp>
+
+#include "figure.hpp"
+
+using glm::vec3;
+using glm::normalize;
+
+class Plane : public Figure {
+public:
+  vec3 m_point;
+  vec3 m_normal;
+  
+  Plane(): m_point(vec3(0.0f)), m_normal(0.0f, 0.0f, 1.0f) { }
+
+  Plane(float x, float y, float z, float nx, float ny, float nz): m_point(vec3(x, y, z)), m_normal(normalize(vec3(nx, ny, nz))) { }
+
+  Plane(vec3 _p, vec3 _n): m_point(_p), m_normal(normalize(_n)) { }
+
+  virtual ~Plane() { }
+
+  virtual bool intersect(Ray & r, float & t, vec3 & n) const;
+};
+
+
+#endif

sphere.cpp

@@ -30,7 +30,8 @@ bool Sphere::intersect(Ray & r, float & t, vec3 & n) const {
     t = (-b - sqrt(d)) / (2 * a);
     i = vec3(r.m_origin + (t * r.m_direction));
     n = normalize(vec3((i - m_center) / m_radius));
-  }
+    return t >= 0.0f;
 
-  return d >= 0.0f;
+  } else
+    return false;
 }