Two independent URL parameters:
#flight=N|NE|E|SE|S|SW|W|NW (camera motion direction)
#fetch=N|NE|E|SE|S|SW|W|NW (tile collection direction)
Example: #flight=E&fetch=N -> camera flies east, corridor built
north (perpendicular to flight). Lets you test what happens when
the corridor orientation doesn't match the camera's flight path.
URL parsing supports & and ; as separators, plus multiple keys
in one hash. window.__flightDir and window.__fetchDir are exposed
separately so JS code can react to each.
Richard Zink
f21a967643