help can't break window with rock

i am having a hard time getting pass the big log or whatever it is its keeping me from breaking the window please help

That large object, i believe, is a chiminey. I got past it by expierimenting with the angle of the shot and if u hold the left side mouse button down, u'll see it will bring up a little button that will allow u the power to decide how hard u want to throw the rock. u have to hit the window a few times, it cracks more and more, then it will break the 3rd or so time u hit it. Just keep trying different angles and hardness of the throw and u'll get it. Good luck!!