Add get_ambient() to Scene

src/scene.cc

@@ -19,7 +19,7 @@
 Scene::Scene()
     : width(640), height(480),
       max_depth(5),
-      ambient(NULL),
+      ambient(new AmbientLight()),
       shapes(),
       lights(),
       nrays(0),
@@ -74,6 +74,14 @@ Scene::get_height()
 }
 
 
+AmbientLight &
+Scene::get_ambient()
+    const
+{
+    return *ambient;
+}
+
+
 const Color *
 Scene::get_pixels()
     const

src/scene.h

@@ -31,6 +31,7 @@ public:
     bool is_rendered() const;
     int get_width() const;
     int get_height() const;
+    AmbientLight &get_ambient() const;
     const Color *get_pixels() const;
 
     void read(const std::string &filename);