This variable can be used to get or to set the position of an
instance along its current path in the previous step, and is a
normalised value between 0 and 1 ie: 0 is the start position of the
path and 1 would be the end position. It is similar to the xprevious
functions in how it works, only it is specific for paths. It can be
useful for things like temporarily stopping a path follower if
something is in the way (see the example code below).
var xx, yy;
xx = x + lengthdir_x(16, direction);
yy = y + lengthdir_y(16, direction);
if collision_circle(xx, yy, 16, obj_Player, false,true) path_position = path_positionprevious;
The above code checks an area in front of the instance for a collision with the object "obj_Player" and if there is one, it sets the instance back to the previous position it occupied on the current path.