6 files changed, 37 insertions, 19 deletions
diff --git a/src/world/container.rs b/src/world/container/list.rs
index 6f8c182..c8e3fdd 100644
--- a/src/world/container.rs
+++ b/src/world/container/list.rs
@@ -1,5 +1,6 @@
-use super::{Hittable, Intersection};
-use crate::core::Ray;
+use crate::world::{Hittable, Intersection};
+use crate::core::{Bound3f, Ray};
+
 
 pub struct HittableList {
     elems: Vec<Box<dyn Hittable>>,
@@ -32,6 +33,17 @@ impl Hittable for HittableList {
 
         min
     }
+
+    fn bounding_box(&self) -> Bound3f {
+        let mut bound: Bound3f = Bound3f::EMPTY;
+
+        for e in self.elems.iter() {
+            let eb = e.bounding_box();
+            bound = bound.combine(&eb);
+        }
+
+        bound
+    }
 }
 
 impl Default for HittableList {
@@ -41,3 +53,4 @@ impl Default for HittableList {
         }
     }
 }
+
diff --git a/src/world/container/mod.rs b/src/world/container/mod.rs
new file mode 100644
index 0000000..35d4693
--- /dev/null
+++ b/src/world/container/mod.rs
@@ -0,0 +1,3 @@
+mod list;
+
+pub use list::HittableList;
diff --git a/src/world/hittable.rs b/src/world/hittable.rs
index 720a019..c5a353e 100644
--- a/src/world/hittable.rs
+++ b/src/world/hittable.rs
@@ -27,7 +27,5 @@ pub trait Hittable: Sync + Send {
     fn intersect(&self, ray: &Ray) -> Option<Intersection>;
 
     /// Returns the axis alligned bounding box containing self
-    fn bounding_box(&self) -> Option<Bound3f> {
-        None
-    }
+    fn bounding_box(&self) -> Bound3f;
 }
diff --git a/src/world/mod.rs b/src/world/mod.rs
index 43f7530..53d8ad3 100644
--- a/src/world/mod.rs
+++ b/src/world/mod.rs
@@ -2,11 +2,10 @@
 pub mod shapes;
 
 mod scene;
-mod container;
+pub mod container;
 mod hittable;
 pub use scene::*;
 pub use hittable::{Intersection, Hittable};
-pub use container::HittableList;
 
 use std::sync::Arc;
 use crate::material::Material;
@@ -31,7 +30,7 @@ impl Hittable for Object {
         self.shape.intersect(ray).map(|mut i| {i.m = Some(self.mat.as_ref()); i})
     }
 
-    fn bounding_box(&self) -> Option<Bound3f> {
+    fn bounding_box(&self) -> Bound3f {
         self.shape.bounding_box()
     }
 }
diff --git a/src/world/scene.rs b/src/world/scene.rs
index 03578be..6d15fc1 100644
--- a/src/world/scene.rs
+++ b/src/world/scene.rs
@@ -1,9 +1,11 @@
-use crate::core::Ray;
+use crate::core::{Bound3f, Ray};
 
-use super::{Object, HittableList, Hittable, Intersection};
+use super::{Object, container, Hittable, Intersection};
+
+type Container = container::HittableList;
 
 pub struct Scene {
-    content: HittableList,
+    content: Container,
 }
 
 impl Scene {
@@ -26,12 +28,16 @@ impl Hittable for Scene {
     fn intersect(&self, ray: &Ray) -> Option<Intersection> {
         self.content.intersect(ray)
     }
+
+    fn bounding_box(&self) -> Bound3f {
+        self.content.bounding_box()
+    }
 }
 
 impl Default for Scene {
     fn default() -> Self {
         Self {
-            content: HittableList::new(),
+            content: Container::new(),
         }
     }
 }
diff --git a/src/world/shapes/sphere.rs b/src/world/shapes/sphere.rs
index 55fc8b4..e3348de 100644
--- a/src/world/shapes/sphere.rs
+++ b/src/world/shapes/sphere.rs
@@ -57,19 +57,18 @@ impl Hittable for Sphere {
     /// # Examples
     ///
     /// ```
-    /// use rendering::core::{Vector3f, Hittable};
-    /// use rendering::world::shapes::Sphere;
+    /// use rendering::core::Vector3f;
+    /// use rendering::world::{Hittable, shapes::Sphere};
     ///
     /// let sph = Sphere::new(1.0, Vector3f::new(0.0));
-    /// let b = sph.bounding_box().unwrap();
+    /// let b = sph.bounding_box();
     ///
     /// assert!(b.min.x == -1.0 && b.min.y == -1.0 && b.min.z == -1.0);
     /// assert!(b.max.x == 1.0 && b.max.y == 1.0 && b.max.z == 1.0);
-    fn bounding_box(&self) -> Option<Bound3f> {
+    fn bounding_box(&self) -> Bound3f {
         let offset = Vector3f::new(self.radius);
-        Some(
-            Bound3f::new(self.center - offset, self.center + offset)
-            )
+
+        Bound3f::new(self.center - offset, self.center + offset)
     }
 }