Child Relocation, planning to move out of the state of Texas to Oklahoma?

I have joint custody with the father of my child, but I'm getting married soon and planing to move out of Texas to Oklahoma with my husband where he is stationed, he's in the military. The father of my child is paying child support but he's not a good example for my child, and I know that he would not allow me to take my child out of the state. I read the agreement we both signed and it says that I have the right the decide the residence of the child without regard to the geographic location. Does that mean that I can take my son out the state without any problems? I want to fight for full custody as well.