Try this alternative method, which is a lot more efficient and which allows you to work with a gradient. It’s well worth knowing about this technique because it has many uses.
Add a gradient generator (1920×1080 in a 1080 project) and set the Start X and Y to zero, End X to say 1440 (or to taste) and End Y to zero. (Make sure it is centred on the canvas.)
Make the enclosing group Fixed Resolution and add a Polar filter to the group. Use a circular mask as necessary to crop the outside of the circle to the required size.
Now simply animate the X position of the gradient – start at negative 1920 and end at positive 1920.
Obviously by adjusting the gradient itself you can achieve a whole range of different and interesting results. Or you could simply use the result as a matte for your own fill.
The Polar filter can seem confusing at first if you’re not used to the concept but it can be immensely useful for this kind of thing.
Simon Ubsdell
tokyo productions
hawaiki