I'll try to be brief and with no links so I won't get disapproved again.

Okay, I want to create an affect like the earlier Final Fantasies where a menu/dialogue box is drawn from the top down. In the early games, it looks like the menu is rendered but it's initially set to transparent. In a split second, it's drawn from the top down giving it an animated effect.
I tried recreating that effect using inverted stencils where I called a rectangle stencil to set up transparency, drew the dialogue window, and then animated the stencil's position based on the width, height, x and y pos of the dialogue window. I thought this would just sort of mask the image its on top of but stencils seem to cut all the way to the background color and don't just stop at the previous layers.
Is there a way to do what I described with or without stencils?