That said, the CG Leia was poorly executed, which was a surprise considering how well Tarkin was done. She really looked like a video game character. I would have preferred showing her head covered by her scarf and only showing her hands, like her intro in Episode 4. Maybe the production was worried casual fans wouldn't know who it was if they didn't show the face and goofy side-buns?
http://postnewsgroup.com/wp-content/uploads/2016/12/CGI-Pete...
It was CGI over a mo-capped live actor.
I certainly didn't notice it was CG while I was watching the film. Nor did my wife, who was watching it with me.
But Mons Mothra looked fine, and I didn't get to see enough enough of Leia to tell --- and the other CGI actors I didn't know were CGI and completely failed to notice.
So it's definitely getting better. This was no _Polar Express_.
No CGI trickery here.
Well, that does explain why she looked so realistic!
https://moviepilot.com/p/unused-new-hope-footage-rogue-one/4...
http://www.radiotimes.com/news/2016-12-19/the-unseen-star-wa...
It was the other way around. They found the old footage of the actors, and "CGd" the new cockpit etc. onto them.