Correctly render multiple objects instead of just rendeing one

src/camera.rs

@@ -68,15 +68,23 @@ pub fn render_scene<T: RealField>(output_image: &mut OutputImage, scene: &Scene<
     for column in 0..output_image.get_width() {
         for row in 0..output_image.get_height() {
             let ray = image_sampler.ray_for_pixel(row, column);
-            for object in scene.objects.iter() {
+            let hit = scene
-                let gray = match object.intersect(&ray) {
+                .objects
+                .iter()
+                .flat_map(|object| object.intersect(&ray))
+                .min_by(
+                    |a, b| match PartialOrd::partial_cmp(&a.distance, &b.distance) {
+                        None => std::cmp::Ordering::Less,
+                        Some(ordering) => ordering,
+                    },
+                );
+            let gray = match hit {
                 None => 0,
                 Some(_) => 255,
             };
             output_image.set_color(row, column, gray, gray, gray);
         }
     }
-    }
 }
 
 #[cfg(test)]