Child support?

In determining the amount of child support to be paid, I know they look at both parents income, but if the state has a scale that determines your child support by how much money you earn, does it even matter what the custodial parent makes? In other words if I make 50,000, and my ex and her new husband make a combined total of 80,000, I will still pay whatever the scale says,,,correct? I am asking this on my girlfriends yahoo account, in case you were fooled by the name. This is an argument we are having, and she also says that because I pay child support I have visitation rights. I know this is incorrect, but I am trying to settle the argument! Can I please get some input?