I have a project which requires that I have some scrolling text that doesn't touch the top or bottom 1/4 of the screen. The reason is that the background clip contains date and title into which can't be obscured by the scrolling text.
Just as you asked...create a mask.
Use the Gradient generator to create a mask that is clear in the middle and gradiented to black at the top/bottom. Then child it to the text track, and you'll be done. Check the http://www.vasst.com/login.htm site, I uploaded a credit roll and mask for you.
That was very generous of you to upload that file. One question: you say above, " ... Then child it to the text track ... " In fact, it isn't set as a child in your VEG file, and you actually don't need to, given the way your mask is constructed. Am I correct in this observation? I think your method has the advantage of probably rendering faster than if you used a parent/child track, although I may be wrong on that one.
I know...I changed my process halfway through and didn't edit my post. Sometimes it's just faster to do something and upload it than it is to describe it and probably lose a lot in the translation. :-) I'm a terrible communicator sometimes.
Create your credit roll timeline event
Open the credit roll event's pan/crop dialog box
Set "stretch to fill frame" to NO
Adjust lower and upper (Y) position of the crop rectangle as needed
Yeah, I did that too, but didn't like the hard edged text coming in, hence the softened edge from the mask.
Like most things in Vegas, there are a dozen ways to accomplish the same/similar results!
> there are a dozen ways to accomplish the same/similar results!
Yep there sure are. Here’s another: We are so use to masking with generated media that we often forget that in Vegas 5 you can just click Pan/Crop, enable the Mask keyframes and draw a box where you want the credit roll to be visible. Then set the Feather Type to In and Feather (%) to about 5.0 and you have the desired effect all on one track so when you move the event there is no mask to move with it. Vegas 5 Rocks!