Change the Intersection to a class, and stop using memory allocation for it (and pointer)

A bit more clean (on the code side)

source/include/intersect.h

@@ -15,14 +15,14 @@
 class Intersect
 {
 private:
-    Intersection **list;
+    Intersection *list;
     uint32_t num;
     uint32_t allocated;
 public:
     Intersect();
-    void add(Intersection *i);
+    void add(Intersection i);
     int count() { return this->num; };
-    Intersection *operator[](const int p) { return this->list[p]; }
+    Intersection operator[](const int p) { return this->list[p]; }
 };
 
 #endif //DORAYME_INTERSECT_H

source/include/intersection.h

@@ -13,31 +13,14 @@
 
 class Object;
 
-struct Intersection
+class Intersection
 {
+public:
     double t;
     Object *object;
+
+public:
+    Intersection(double t, Object *object) : t(t), object(object) { };
 };
 
-static Intersection *newIntersection(double t, Object *object)
-{
-    Intersection *ret = (Intersection *)calloc(sizeof(Intersection), 1);
-
-    if (ret != nullptr)
-    {
-        ret->t = t;
-        ret->object = object;
-    }
-
-    return ret;
-}
-
-static void freeIntersection(Intersection *i)
-{
-    if ( i != nullptr )
-    {
-        free(i);
-    }
-}
-
 #endif //DORAYME_INTERSECTION_H

source/intersect.cpp

@@ -15,16 +15,16 @@
 Intersect::Intersect()
 {
     this->allocated = MIN_ALLOC;
-    this->list = (Intersection **)calloc(sizeof(Object *), MIN_ALLOC);
+    this->list = (Intersection *)calloc(sizeof(Object *), MIN_ALLOC);
     this->num = 0;
 }
 
-void Intersect::add(Intersection *i)
+void Intersect::add(Intersection i)
 {
     if ((this->num + 1) < this->allocated)
     {
         this->allocated *= 2;
-        this->list = (Intersection **)realloc(this->list, sizeof(Object *) * this->allocated);
+        this->list = (Intersection *)realloc(this->list, sizeof(Object *) * this->allocated);
     }
     this->list[this->num++] = i;
 }

source/objects/sphere.cpp

@@ -27,8 +27,8 @@ Intersect Sphere::intersect(Ray r)
 
     if (discriminant >= 0)
     {
-        ret.add(newIntersection((-b - sqrt(discriminant)) / (2 * a), this));
-        ret.add(newIntersection((-b + sqrt(discriminant)) / (2 * a), this));
+        ret.add(Intersection((-b - sqrt(discriminant)) / (2 * a), this));
+        ret.add(Intersection((-b + sqrt(discriminant)) / (2 * a), this));
     }
 
     return ret;

tests/intersect_test.cpp

@@ -17,35 +17,46 @@ TEST(IntersectTest, Creating_an_intersect_and_do_some_check)
 
     ASSERT_EQ(i.count(), 0);
 
-    i.add(newIntersection(1.0, nullptr));
-    i.add(newIntersection(4.2, nullptr));
+    i.add(Intersection(1.0, nullptr));
+    i.add(Intersection(4.2, nullptr));
 
     ASSERT_EQ(i.count(), 2);
 
-    ASSERT_EQ(i[0]->t, 1.0);
-    ASSERT_EQ(i[1]->t, 4.2);
+    ASSERT_EQ(i[0].t, 1.0);
+    ASSERT_EQ(i[1].t, 4.2);
 }
 
 TEST(IntersectTest, An_intersection_encapsulate_t_and_object)
 {
     Sphere s = Sphere();
-    Intersection *i = newIntersection(3.5, &s);
+    Intersection i = Intersection(3.5, &s);
 
-    ASSERT_EQ(i->t, 3.5);
-    ASSERT_EQ(i->object, (Object *)&s);
+    ASSERT_EQ(i.t, 3.5);
+    ASSERT_EQ(i.object, (Object *)&s);
 }
 
 TEST(IntersectTest, Aggregating_intersections)
 {
     Sphere s = Sphere();
-    Intersection *i1 = newIntersection(1, &s);
-    Intersection *i2 = newIntersection(2, &s);
+    Intersection i1 = Intersection(1, &s);
+    Intersection i2 = Intersection(2, &s);
 
     Intersect xs = Intersect();
     xs.add(i1);
     xs.add(i2);
 
     ASSERT_EQ(xs.count(), 2);
-    ASSERT_EQ(xs[0]->t, 1);
-    ASSERT_EQ(xs[1]->t, 2);
+    ASSERT_EQ(xs[0].t, 1);
+    ASSERT_EQ(xs[1].t, 2);
+}
+
+TEST(IntersectTest, Intersect_sets_the_object_on_the_intersection)
+{
+    Ray r = Ray(Point(0, 0, -5), Vector(0, 0, 1));
+    Sphere s = Sphere();
+    Intersect xs = s.intersect(r);
+
+    ASSERT_EQ(xs.count(), 2);
+    ASSERT_EQ(xs[0].object, (Object *)&s);
+    ASSERT_EQ(xs[1].object, (Object *)&s);
 }

tests/sphere_test.cpp

@@ -18,8 +18,8 @@ TEST(SphereTest, A_ray_intersect_a_sphere_at_two_points)
     Intersect xs = s.intersect(r);
 
     ASSERT_EQ(xs.count(), 2);
-    ASSERT_EQ(xs[0]->t, 4.0);
-    ASSERT_EQ(xs[1]->t, 6.0);
+    ASSERT_EQ(xs[0].t, 4.0);
+    ASSERT_EQ(xs[1].t, 6.0);
 }
 
 TEST(SphereTest, A_ray_intersect_a_sphere_at_a_tangent)
@@ -29,8 +29,8 @@ TEST(SphereTest, A_ray_intersect_a_sphere_at_a_tangent)
     Intersect xs = s.intersect(r);
 
     ASSERT_EQ(xs.count(), 2);
-    ASSERT_EQ(xs[0]->t, 5.0);
-    ASSERT_EQ(xs[1]->t, 5.0);
+    ASSERT_EQ(xs[0].t, 5.0);
+    ASSERT_EQ(xs[1].t, 5.0);
 }
 
 TEST(SphereTest, A_ray_miss_a_sphere)
@@ -49,8 +49,8 @@ TEST(SphereTest, A_ray_originate_inside_a_sphere)
     Intersect xs = s.intersect(r);
 
     ASSERT_EQ(xs.count(), 2);
-    ASSERT_EQ(xs[0]->t, -1.0);
-    ASSERT_EQ(xs[1]->t, 1.0);
+    ASSERT_EQ(xs[0].t, -1.0);
+    ASSERT_EQ(xs[1].t, 1.0);
 }
 
 TEST(SphereTest, A_sphere_is_behind_a_ray)
@@ -60,6 +60,6 @@ TEST(SphereTest, A_sphere_is_behind_a_ray)
     Intersect xs = s.intersect(r);
 
     ASSERT_EQ(xs.count(), 2);
-    ASSERT_EQ(xs[0]->t, -6.0);
-    ASSERT_EQ(xs[1]->t, -4.0);
+    ASSERT_EQ(xs[0].t, -6.0);
+    ASSERT_EQ(xs[1].t, -4.0);
 }