http://rathena.org/wiki/Adding_a_Script#A_New_Script
https://rathena.svn.sourceforge.net/svnroot/rathena/trunk/npc/warps/
** Define a warp point
<from map name>,<fromX>,<fromY>,<facing>%TAB%warp%TAB%<warp name>%TAB%<spanx>,<spany>,<to map name>,<toX>,<toY>
This will define a warp NPC that will warp a player between maps, and while most
arguments of that are obvious, some deserve special mention.
SpanX and SpanY will make the warp sensitive to a character who didn't step
directly on it, but walked into a zone which is centered on the warp from
coordinates and is SpanX in each direction across the X axis and SpanY in each
direction across the Y axis.
Warp NPC objects also have a name, because you can use it to refer to them later
with 'enablenpc'/'disablenpc'
Facing of a warp object is irrelevant, it is not used in the code and all
current scripts have a zero in there.