Just click on the projectile you want to start. It will always use the shortest route to your mouse. It also uses a smart turner, so it will not instantly be pointing at your mouse, but will still get it. It will eventually glitch out and stop chasing your mouse, but if you wait 2 seconds, it will work again.
I used all of my own code. It is all in One Sprite. The Orange Will DESTROY YOU if you turn it all the way up. Like, please (I think, I don't know if it actually means anything).