TileMap is scaled down when running on Android with high resolution

cocos2d-x C++
1

My layer contains many TMXTiledMap. It looks fine on win32, but heavily scaled down on Android phone. There come a lot gaps between two TMXTiledMap. Yellow rects are tmx maps.

2

I found out that I just need to scale by the global content scale factor.

auto map = cocos2d::experimental::TMXTiledMap::create("tile.tmx");
auto director = Director::getInstance();
map->setScale(director->getContentScaleFactor());