first commit

src/camera.h

@@ -0,0 +1,11 @@
+#include "vector.h"
+
+typedef enum {
+    UP, DOWN, LEFT, RIGHT,
+} Direction;
+
+Matrix4 camera_pov(void);
+void move_camera(Direction dir, float speed);
+void rotate_camera(double mouse_x, double mouse_y);
+Vector3 get_camera_pos(void);
+Ray ray_through_screen_at(float u, float v, float aspect_ratio);