You can specify pixel coordinates or link to a window location:
Code:
import viz
viz.go()
#set position in pixel coordinates
text1 = viz.addText('text1',parent=viz.ORTHO)
text1.setScale([100,100,0])
text1.setPosition([300,200,0])
#link to center top
text2 = viz.addText('text2',parent=viz.ORTHO)
text2.setScale([100,100,0])
text2.alignment(viz.ALIGN_CENTER_TOP)
viz.link(viz.CenterTop,text2)
#link to upper left with offset
text3 = viz.addText('text3',parent=viz.ORTHO)
text3.setScale([100,100,0])
text3.alignment(viz.ALIGN_LEFT_TOP)
link = viz.link(viz.LeftTop,text3)
link.setOffset([20,-20,0])