New lighting object tree: AmbientLight -> PointLight

src/charles.cc

@@ -41,8 +41,10 @@ main(int argc,
     scene.add_shape(s2);
     scene.add_shape(s3);
 
-    Light *l1 = new Light(Vector3(500.0, 100.0, 600.0), 1.0);
+    PointLight *l1 = new PointLight(Vector3(0.0, 240.0, 100.0), Color(1.0, 1.0, 1.0), 1.0);
+    //Light *l2 = new Light(Vector3(640.0, 240.0, 10000.0), 0.2);
     scene.add_light(l1);
+    //scene.add_light(l2);
 
     // Render.
     scene.render();

src/light.cc

@@ -9,38 +9,85 @@
 #include "light.h"
 #include "object.h"
 
+#pragma mark - Ambient Lights
 
-Light::Light()
+AmbientLight::AmbientLight()
-    : Light(1.0)
+    : AmbientLight(Color::White)
 { }
 
 
-Light::Light(float i)
+AmbientLight::AmbientLight(const Color &c)
-    : Light(Vector3::Zero, i)
+    : AmbientLight(c, 1.0)
 { }
 
 
-Light::Light(Vector3 o, float i)
+AmbientLight::AmbientLight(const Color &c, const float &i)
-    : Object(o),
+    : color(c),
       intensity(i)
-{ }
+{
+    _clamp_intensity();
+}
 
 
-/*
+const Color &
- * Light::get_intensity --
+AmbientLight::get_color()
- * Light::set_intensity --
+    const
- *
+{
- * Get and set the intensity of this light.
+    return color;
- */
+}
-float
+
-Light::get_intensity()
+
+const float &
+AmbientLight::get_intensity()
     const
 {
     return intensity;
 }
 
-void
+
-Light::set_intensity(float i)
+Color
+AmbientLight::compute_color_contribution()
+    const
 {
-    intensity = i;
+    return color * intensity;
 }
+
+
+void
+AmbientLight::_clamp_intensity()
+{
+    if (intensity < 0.0) {
+        intensity = 0.0;
+    }
+    else if (intensity > 1.0) {
+        intensity = 1.0;
+    }
+}
+
+#pragma mark - Point Lights
+
+PointLight::PointLight()
+    : AmbientLight(),
+      Object()
+{ }
+
+
+PointLight::PointLight(const Vector3 &o)
+    : AmbientLight(),
+      Object(o)
+{ }
+
+
+PointLight::PointLight(const Vector3 &o,
+                       const Color &c)
+    : AmbientLight(c),
+      Object(o)
+{ }
+
+
+PointLight::PointLight(const Vector3 &o,
+                       const Color &c,
+                       const float &i)
+    : AmbientLight(c, i),
+      Object(o)
+{ }

src/light.h

@@ -12,19 +12,36 @@
 #include "object.h"
 
 
-class Light
+class AmbientLight
-    : public Object
 {
 public:
-    Light();
+    AmbientLight();
-    Light(float i);
+    AmbientLight(const Color &c);
-    Light(Vector3 o, float i);
+    AmbientLight(const Color &c, const float &i);
 
-    float get_intensity() const;
+    const Color &get_color() const;
-    void set_intensity(float i);
+    const float &get_intensity() const;
+
+    Color compute_color_contribution() const;
+
+protected:
+    Color color;
+    float intensity;
 
 private:
-    float intensity;
+    void _clamp_intensity();
+};
+
+
+class PointLight
+    : public AmbientLight,
+      public Object
+{
+public:
+    PointLight();
+    PointLight(const Vector3 &o);
+    PointLight(const Vector3 &o, const Color &c);
+    PointLight(const Vector3 &o, const Color &c, const float &i);
 };
 
 #endif

src/scene.cc

@@ -140,7 +140,7 @@ Scene::add_shape(Shape *shape)
  * Add a light to the scene.
  */
 void
-Scene::add_light(Light *light)
+Scene::add_light(PointLight *light)
 {
     lights.push_back(light);
 }
@@ -186,7 +186,7 @@ Scene::trace_ray(const Ray &ray, const int depth)
     Vector3 intersection = ray.parameterize(nearest_t);
     Vector3 normal = intersected_shape->compute_normal(intersection);
 
-    for (Light *l : lights) {
+    for (PointLight *l : lights) {
         Vector3 light_direction = (intersection - l->get_origin()).normalize();
         float ldotn = light_direction.dot(normal);
         out_color.red *= ((ldotn >= 0.0) ? ldotn : 0.0) * l->get_intensity();

src/scene.h

@@ -16,7 +16,8 @@
 #include "basics.h"
 
 
-class Light;
+class AmbientLight;
+class PointLight;
 class Shape;
 class Writer;
 
@@ -37,7 +38,7 @@ public:
     void render();
 
     void add_shape(Shape *obj);
-    void add_light(Light *light);
+    void add_light(PointLight *light);
 
 private:
     Color trace_ray(const Ray &ray, const int depth);
@@ -50,7 +51,7 @@ private:
 
     // Scene objects.
     std::list<Shape *> shapes;
-    std::list<Light *> lights;
+    std::list<PointLight *> lights;
 
     // Rendering stats
     unsigned int nrays;