Room events

Event	Handler arguments and meaning
start	function() once when the copy starts, before players enter
enter	function(player) when someone joins
leave	function(player) when someone leaves
click	function(player, thing) after the player reaches the clicked thing
walk_on	function(player, thing) when stepping onto a visible thing
walk_off	function(player, thing) when stepping off
timer	function(tag) for an after or every timer
key	function(player, key) for game keys such as space, w, up, 1
ui	function(player, id, value) for a button, submitted input or selected friend
window_closed	function(player, id) when the player clicks the native window X
send_failed	function(player, room, why) when a scripted room transfer fails

player contains id and name. thing contains id, name, x, y, hidden, and item (the id of the item it is an instance of). Most object/player arguments accept a table or its id string; use the player table for overloaded UI verbs such as banner(player, text). players() additionally provides player x and y. player(idOrPlayer) returns the current row for just one player in this copy, or nil if absent. Use that when updating a bounded group in a large room, to avoid constructing a Lua table for everyone on each tick. Coordinates are tiles local to the room, starting at (0, 0).