I’m a bit confused about polyline position and polyline origin. I suppose that the polyline position is the bottom-left corner of the rectangle which incapsulate the polyline. Is it correct?
And… the second question: Where is the polyline origin?
Sorry for my poor english, i hope it was clear.
Each polygon object is made up of a space-delimited list of x,y coordinates. The origin for these coordinates is the location of the parent object. By default, the first point is created as 0,0 denoting that the point will originate exactly where the object is placed.
This does not talk about any bounding rectangle of the polygon/polyline. The origin for the points on the polygon/polyline is simply the position of the object.
The origin of the polyline object is the same as the origin for any object, which is in the top-left for orthogonal maps and the top-center for isometric maps.