Use shared_ptr for materials and objects

For src/inOneWeekend code only.

Author: hollasch

src/InOneWeekend/hittable.h

@@ -19,7 +19,7 @@ class material;
 struct hit_record {
     vec3 p;
     vec3 normal;
-    material *mat_ptr;
+    shared_ptr<material> mat_ptr;
     double t;
     bool front_face;
 

src/InOneWeekend/hittable_list.h

@@ -18,15 +18,15 @@
 class hittable_list: public hittable  {
     public:
         hittable_list() {}
-        hittable_list(hittable* object) { add(object); }
+        hittable_list(shared_ptr<hittable> object) { add(object); }
 
-        void clear()               { objects.clear(); }
-        void add(hittable* object) { objects.push_back(object); }
+        void clear() { objects.clear(); }
+        void add(shared_ptr<hittable> object) { objects.push_back(object); }
 
         virtual bool hit(const ray& r, double tmin, double tmax, hit_record& rec) const;
 
     public:
-        std::vector<hittable*> objects;
+        std::vector<shared_ptr<hittable>> objects;
 };
 
 

src/InOneWeekend/main.cc

@@ -41,7 +41,9 @@ vec3 ray_color(const ray& r, hittable& world, int depth) {
 hittable_list random_scene() {
     hittable_list objects;
 
-    objects.add(new sphere(vec3(0,-1000,0), 1000, new lambertian(vec3(0.5, 0.5, 0.5))));
+    objects.add(
+        make_shared<sphere>(vec3(0,-1000,0), 1000, make_shared<lambertian>(vec3(0.5, 0.5, 0.5)))
+    );
 
     int i = 1;
     for (int a = -11; a < 11; a++) {
@@ -52,23 +54,28 @@ hittable_list random_scene() {
                 if (choose_mat < 0.8) {
                     // diffuse
                     auto albedo = vec3::random() * vec3::random();
-                    objects.add(new sphere(center, 0.2, new lambertian(albedo)));
+                    objects.add(
+                        make_shared<sphere>(center, 0.2, make_shared<lambertian>(albedo)));
                 } else if (choose_mat < 0.95) {
                     // metal
                     auto albedo = vec3::random(.5, 1);
                     auto fuzz = random_double(0, .5);
-                    objects.add(new sphere(center, 0.2, new metal(albedo, fuzz)));
+                    objects.add(
+                        make_shared<sphere>(center, 0.2, make_shared<metal>(albedo, fuzz)));
                 } else {
                     // glass
-                    objects.add(new sphere(center, 0.2, new dielectric(1.5)));
+                    objects.add(make_shared<sphere>(center, 0.2, make_shared<dielectric>(1.5)));
                 }
             }
         }
     }
 
-    objects.add(new sphere(vec3(0, 1, 0), 1.0, new dielectric(1.5)));
-    objects.add(new sphere(vec3(-4, 1, 0), 1.0, new lambertian(vec3(0.4, 0.2, 0.1))));
-    objects.add(new sphere(vec3(4, 1, 0), 1.0, new metal(vec3(0.7, 0.6, 0.5), 0.0)));
+    objects.add(
+        make_shared<sphere>(vec3(0, 1, 0), 1.0, make_shared<dielectric>(1.5)));
+    objects.add(
+        make_shared<sphere>(vec3(-4, 1, 0), 1.0, make_shared<lambertian>(vec3(0.4, 0.2, 0.1))));
+    objects.add(
+        make_shared<sphere>(vec3(4, 1, 0), 1.0, make_shared<metal>(vec3(0.7, 0.6, 0.5), 0.0)));
 
     return objects;
 }

src/InOneWeekend/sphere.h

@@ -18,11 +18,16 @@
 class sphere: public hittable  {
     public:
         sphere() {}
-        sphere(vec3 cen, double r, material *m) : center(cen), radius(r), mat_ptr(m)  {};
+
+        sphere(vec3 cen, double r, shared_ptr<material> m)
+            : center(cen), radius(r), mat_ptr(m) {};
+
         virtual bool hit(const ray& r, double tmin, double tmax, hit_record& rec) const;
+
+    public:
         vec3 center;
         double radius;
-        material *mat_ptr;
+        shared_ptr<material> mat_ptr;
 };
 
 

src/common/rtweekend.h

@@ -12,8 +12,14 @@
 #include <cstdlib>
 #include <limits>
 #include <cmath>
+#include <memory>
 
 
+// Usings
+
+using std::shared_ptr;
+using std::make_shared;
+
 // Constants
 
 const double infinity = std::numeric_limits<double>::infinity();