Sets the current point to new coordinates. If this is the first call of ps_moveto() after a previous path has been ended then it will start a new path. If this function is called in the middle of a path it will just set the current point and start a subpath.
psdocResource identifier of the postscript file as returned by ps_new().
xx-coordinate of the point to move to.
yy-coordinate of the point to move to.