@dcnieho, that's a great idea, it works great and you were right I don't have to worry about setting the position.
Code:
global HideSphere
HideSphere = vizshape.addQuad(size=[1,1])
HideSphere.setParent(viz.SCREEN)
HideSphere.setPosition(0.5,0.5,0)
HideSphere.color(0,0,0)