When I use cmd+F to get VLC into fullscreen while running a video, there's a transition effect (the video expands diagonally until it's fullscreen). [Incidentally, this generally causes the currently-playing frame to expand, which takes some time, so I see an individual frame during the expansion, then jump to
current-time + transition time without seeing the intervening frames].
I can't seem to find the option to get rid of the transition effect. I want to jump straight from small- to full-screen video while playing.