There are several methods I've seen in the news over the last year or so that might account for it; whatever it is, though, it encloses a relatively small volume. Note that she doesn't move very far from the point where she rose up out of the stage. And the stage design, with those curving, enclosing "beams", effectively reduce the performing space, and thus make it less obvious that she's not ranging from one end of the stage to another.
One possibility might be that she's projected on a vertical sheet of glass or plexiglas which is spinning; different lasers paint different angles at different points in its rotation.
As for the performance itself, Disney already does something similar with its "Monsters, Inc." attraction, in which projected computer-generated characters interact with the audience in real-time. I suspect that there's a very real actress/dancer somewhere out of sight tagged for motion capture, who drives the movements of the animated figure, and gets some kind of visual feed on the stage and at least the first row or two so she can wave to or otherwise respond to nearby audience members. It'd be interesting to find out if "Miku" actually talks to the audience; if she does, I wonder who's in charge of her dialogue and how much of it is allowed to be spontaneous.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.
One possibility might be that she's projected on a vertical sheet of glass or plexiglas which is spinning; different lasers paint different angles at different points in its rotation.
As for the performance itself, Disney already does something similar with its "Monsters, Inc." attraction, in which projected computer-generated characters interact with the audience in real-time. I suspect that there's a very real actress/dancer somewhere out of sight tagged for motion capture, who drives the movements of the animated figure, and gets some kind of visual feed on the stage and at least the first row or two so she can wave to or otherwise respond to nearby audience members. It'd be interesting to find out if "Miku" actually talks to the audience; if she does, I wonder who's in charge of her dialogue and how much of it is allowed to be spontaneous.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.