libdeng2: Added equality operators for integer vectors

Unlike floating point vectors, integer vectors have unambiguously
defined equality.

doomsday/libdeng2/include/de/vector.h

@@ -407,6 +407,37 @@ QTextStream &operator << (QTextStream &os, Vector4<Type> const &vec4)
     return os;
 }
 
+// Equality operators for integer types.
+inline bool operator == (Vector2<dint> const &a, Vector2<dint> const &b)
+{
+    return a.x == b.x && a.y == b.y;
+}
+
+inline bool operator == (Vector3<dint> const &a, Vector3<dint> const &b)
+{
+    return a.x == b.x && a.y == b.y && a.z == b.z;
+}
+
+inline bool operator == (Vector4<dint> const &a, Vector4<dint> const &b)
+{
+    return a.x == b.x && a.y == b.y && a.z == b.z && a.w == b.w;
+}
+
+inline bool operator == (Vector2<duint> const &a, Vector2<duint> const &b)
+{
+    return a.x == b.x && a.y == b.y;
+}
+
+inline bool operator == (Vector3<duint> const &a, Vector3<duint> const &b)
+{
+    return a.x == b.x && a.y == b.y && a.z == b.z;
+}
+
+inline bool operator == (Vector4<duint> const &a, Vector4<duint> const &b)
+{
+    return a.x == b.x && a.y == b.y && a.z == b.z && a.w == b.w;
+}
+
 //@{
 /// @ingroup types
 typedef Vector2<dint> Vector2i;     ///< 2-component vector of integer values.