diff --git a/src/newgrf_spritegroup.h b/src/newgrf_spritegroup.h
--- a/src/newgrf_spritegroup.h
+++ b/src/newgrf_spritegroup.h
@@ -78,7 +78,6 @@ public:
  * groups. */
 struct RealSpriteGroup : SpriteGroup {
 	RealSpriteGroup() : SpriteGroup(SGT_REAL) {}
-	~RealSpriteGroup();
 
 	/* Loaded = in motion, loading = not moving
 	 * Each group contains several spritesets, for various loading stages */
@@ -87,10 +86,8 @@ struct RealSpriteGroup : SpriteGroup {
 	 * with small amount of cargo whilst loading is for stations with a lot
 	 * of da stuff. */
 
-	byte num_loaded;       ///< Number of loaded groups
-	byte num_loading;      ///< Number of loading groups
-	const SpriteGroup **loaded;  ///< List of loaded groups (can be SpriteIDs or Callback results)
-	const SpriteGroup **loading; ///< List of loading groups (can be SpriteIDs or Callback results)
+	std::vector<const SpriteGroup *> loaded;  ///< List of loaded groups (can be SpriteIDs or Callback results)
+	std::vector<const SpriteGroup *> loading; ///< List of loading groups (can be SpriteIDs or Callback results)
 
 protected:
 	const SpriteGroup *Resolve(ResolverObject &object) const;