Added indirect illumination.

directional_light.cpp

@@ -20,12 +20,19 @@ inline float DirectionalLight::distance(vec3 point) {
   return numeric_limits<float>::max();
 }
 
-vec3 DirectionalLight::shade(vec3 normal, Ray & r, float t, Material & m) const {
-  float n_dot_l, r_dot_l;
-  vec3 color, ref;
+vec3 DirectionalLight::diffuse(vec3 normal, Ray & r, float t, Material & m) const {
+  float n_dot_l;
+  vec3 color;
 
   n_dot_l = max(dot(normal, m_position), 0.0f);
-  color += (m.m_diffuse / pi<float>()) * m_diffuse * n_dot_l;
+  color += m_diffuse * n_dot_l;
+
+  return color;
+}
+
+vec3 DirectionalLight::specular(vec3 normal, Ray & r, float t, Material & m) const {
+  float r_dot_l;
+  vec3 color, ref;
 
   ref = reflect(m_position, normal);
   r_dot_l = pow(max(dot(ref, r.m_direction), 0.0f), m.m_shininess);