Physical sightlines are another link to live theater in the "on-stage/off-stage" comparisons.
Many theaters mark sightlines in the wings so that the cast knows the extent of the area where the audience can see to either side of the stage. They know that they shouldn't cross that line until they're actually going on-stage. In the theater, the lines are typically marked for the seats on the extreme ends of the front row.
I believe there's other sightlines in backstage areas, not just the parade route. They're typically behind doors that open to allow CM access on-stage. That way CMs can know whether they're out of sight even if the door is suddenly opened.
You can clearly see the lines in this photo from local.live.com:
http://local.live.com/default.aspx?v=2&cp=nr2k3m861cc9&style=o&lvl=2&scene=3928879
Though here it's more of an "area" than a line. The red-painted area on the ground on the off-stage side of the parade doors show the extent of the area that Guests in the park can see when the doors are open. Parade performers need to stay in character and in costume, performing their routines until they exit from this red area. And if they are starting the parade from the Main Street end, they need to be performing by the time they enter the red area. Next time you're watching the parade from near there, note how on the ground on the other side of the doors you can ONLY see red. You can't tell that the pavement becomes plain gray just outside of your view.
That's one thing I love about designing and construction for the theater. You only have to do what the audience sees. In our recent production of My Fair Lady, in the study scene we had these tall walls that stretched up high, and bookshelves on a balcony up above. But only the bottom 4-5' of the bookshelves were painted and the wall coloring didn't go all the way up, because the audience couldn't see it. Step up onto the stage, and suddenly you see crummy unfinished paint jobs jsut out of view, and that the yellow of the study walls suddenly becomes a patchwork of black or red or any number of other colors from past shows.
Another example in the photo from live.com linked above, if you scroll over to the buildings that border both Fronteirland and Adventureland. On the roofs there's a number of little architectural details, like a thatched roof or a little spike tower, kinda plunked here and there. Plain, dull roof all around, and then just this little extra bit sticking up, But from the park, it looks as if it's one fully themed roof.
-Rob
