What Salvini sees are possibilities. She sees what will happen before it happens. She sees how the branch of a tree will react if she pushes it. She sees the various reactions of that branch based on the various ways of interacting with the branch. There are too many possibilities because she isn't the only one interacting with the branch. The wind is also interacting with it.
She doesn't calculate these possibilities. She only sees them. She sees possible futures then she chooses the action that will bring about a favorable reaction. She brushes the branch aside with minimal effort and it slips aside soundlessly to let her pass. Her sight gives her options and she chooses the easiest option to bring about her goal.