Use the PerspectiveCamera to generate primary rays.

src/scene.h

@@ -14,6 +14,7 @@
 #include <list>
 #include <string>
 #include "basics.h"
+#include "camera.h"
 
 
 class AmbientLight;
@@ -49,6 +50,8 @@ private:
     // Pixel dimensions of the image.
     int width, height;
 
+    Camera *camera;
+
     /*
      * Ray tracing parameters. max_depth indicates the maximum depth of the ray tree. min_weight indicates the minimum
      * specular weight to apply before giving up.