I suppose no response means either this is a really dumb question or impossible?
So, I wanted to copy the Polystar paths so I could create a mask from them. The goal is a two second transition where my Polystar expands from the middle of frame A to fill all of the frame and then go back in reverse to reveal frame B. Thus I needed to create something with transparency that could be dropped into Final Cut Pro to serve as the transition between two frames.
Also, I’m pretty sure I spent more time searching for an answer on how to copy Polystar paths than if I had just created new masks from scratch. Oh well.
I’m absolutely sure there’s a better way to do this, but I thought I’d share my terrible solution for those who enjoy terrible solutions: I changed the colors of the Polystar Shapes to either black or white, depending on when I wanted them to be seen. All the Polystars were in one layer, so I changed that layer’s mode to “Silhouette Luma” (so everything that is white becomes transparent), and created a solid underneath at “Normal” mode with the desired color/background image for the (anytime the Polystars are black) visible shapes.
To be honest, I still don’t understand why this works, but it does.
Then, when you add your composition to the render queue, click on Render Settings, and Channels under Video Output needs to be RGB + Alpha and Color is Straight (Unmatted). Magic happens, and you can safely drop your transition into Final Cut Pro with transparency! woo!