1] Add new Track – say at Track 1
2] Add Sample Text Generated Media SONY Text.
3] Delete “Sample Text” and now type an Underscore Line that fills the whole screen, from left to right.
. You should now have a Line on Screen. Yes?
OK . .
4] Click on the Pan/Crop Icon when it appears, Check/Select the Mask Timeline
5] Now Add 4 Points, by using the Anchor Creation Tool, that create a boundary for the length of the Line.
6] Hold Down the Ctrl Key and Drag a COPY of the Keyframe diamond say to 8 Seconds.
7] Go back to the Initial Keyframe, and by draging each of the 4 Anchors Points separately, make the Line Disappear around the Centre of the Frame. Once you have done this you should NOT be able to see any of the Line.
8] Play the 8 second sequence and what you should get is what I’m seeing too, and that is a Line “growing” equally in each direction AWAY from the middle of the screen as the Mask grows in size.
Grazie