Pointless pointers deleted and added a special Background-member

RayTracer/sampling/Scene.cpp

 #include "Scene.h"
 
-Scene::Scene(std::shared_ptr<shapes::Shape> group, cam::CamObs cam,
-             size_t depth)
-    : group(group), cam(cam), depth(depth) {
+Scene::Scene(const shapes::Group& group, const shapes::Background& bg,
+             const cam::CamObs& cam, size_t depth)
+    : group(group), bg(bg), cam(cam), depth(depth) {
 }
 
 util::Vec3 Scene::color(float x, float y) const {
@@ -14,7 +14,10 @@ util::Vec3 Scene::calculateRadiance(const cam::Ray& r, size_t depth) const {
 	if (depth == 0) {
 		return util::Vec3(0, 0, 0);
 	}
-	std::shared_ptr<cam::Hit> h = group->intersect(r);
+	std::shared_ptr<cam::Hit> h = group.intersect(r);
+	if (h == nullptr) {
+		h = bg.intersect(r);
+	}
 	util::Vec3 result;
 	if (h->scatter()) {
 		result =

RayTracer/sampling/Scene.h

 #pragma once
 
 #include "../camera/CamObs.h"
-#include "../shape/Shape.h"
+#include "../shape/Background.h"
+#include "../shape/Group.h"
 #include "Sampler.h"
 
 class Scene : public util::Sampler {
    public:
-	Scene(std::shared_ptr<shapes::Shape> group, cam::CamObs cam, size_t depth);
+	Scene(const shapes::Group& group, const shapes::Background& bg,
+	      const cam::CamObs& cam, size_t depth);
 	util::Vec3 color(float x, float y) const override;
 	util::Vec3 calculateRadiance(const cam::Ray& r, size_t depth) const;
 
    private:
-	std::shared_ptr<shapes::Shape> group;
+	shapes::Background bg;
+	shapes::Group group;
 	cam::CamObs cam;
 	size_t depth;
 };