Make Selection variables private again

src/celengine/category.h

@@ -11,7 +11,7 @@ public:
     {
         size_t operator()(const Selection &s) const
         {
-            return (size_t)s.obj;
+            return (size_t)s.catEntry();
         }
     };
 

src/celengine/selection.h

@@ -23,7 +23,8 @@ class DeepSkyObject;
 class Selection
 {
  public:
-    enum Type {
+    enum Type
+    {
         Type_Nil,
         Type_Star,
         Type_Body,
@@ -32,15 +33,14 @@ class Selection
         Type_Generic
     };
 
-public:
-    Selection() : type(Type_Nil), obj(nullptr) {};
+    Selection() = default;
     Selection(CatEntry *cat) : type(Type_Generic), obj(cat) { checkNull(); };
     Selection(Star* star) : type(Type_Star), obj(star) { checkNull(); };
     Selection(Body* body) : type(Type_Body), obj(body) { checkNull(); };
     Selection(DeepSkyObject* deepsky) : type(Type_DeepSky), obj(deepsky) {checkNull(); };
     Selection(Location* location) : type(Type_Location), obj(location) { checkNull(); };
     Selection(const Selection& sel) : type(sel.type), obj(sel.obj) {};
-    ~Selection() {};
+    ~Selection() = default;
 
     bool empty() const { return type == Type_Nil; }
     double radius() const;
@@ -78,11 +78,14 @@ public:
 
     Type getType() const { return type; }
 
-    // private:
-    Type type;
-    void* obj;
+ private:
+    Type type { Type_Nil };
+    void* obj { nullptr };
 
     void checkNull() { if (obj == nullptr) type = Type_Nil; }
+
+    friend bool operator==(const Selection& s0, const Selection& s1);
+    friend bool operator!=(const Selection& s0, const Selection& s1);
 };