Move rendering functions to own module

include/camera.h

@@ -1,8 +1,7 @@
 #ifndef CAMERA_H
 #define CAMERA_H
 
-#include "img.h"
-#include "scene.h"
+#include "vec3.h"
 
 #include <stdint.h>
 
@@ -10,14 +9,10 @@ typedef struct {
 	vec3_t pos;
 	vec3_t pix_origin, x_step, y_step;
 	uint32_t img_width, img_height;
-	unsigned samples_per_pixel;
 } camera_t;
 
 camera_t camera_init(
     vec3_t pos, vec3_t target, double fov, uint32_t img_width,
-    uint32_t img_height, unsigned samples_per_pixel);
-
-void camera_render(
-    const camera_t *camera, const scene_t *scene, img_t *img_out);
+    uint32_t img_height);
 
 #endif