anchor.diff:      str: String;
   
       passable, active: Boolean;
  -    mask_conf: TJSONArray;
  +    mask_conf, visit_conf: TJSONArray;
       //anim: TDef;
       width_tiles: Integer;
       height_tiles: Integer;
  
positive.code: 
      property IsOverlay: uint8 read FIsOverlay;
  
    end;
  
    { TMaskResource }
  
negative.code: 
        legacy_config.Add('mask', mask_conf);
  
        //TODO: allowedTerrains
  
        visit_conf := CreateJSONArray([]);
        //top line
        if def.IsVisitableFromTop then
          str := '---'
        else
          str := '+++';
        UniqueString(str);
        visit_conf.Add(str);
  
        //middle line
        str := '+-+';
        UniqueString(str);
        visit_conf.Add(str);
  
        //bollom line
        str := '+++';
        UniqueString(str);
        visit_conf.Add(str);
  
        legacy_config.Add('visitableFrom', visit_conf);
  
        full_id := TypToId(def.FTyp, def.FSubType);
        idx := AFullIdToDefMap.IndexOf(full_id);
  