The cpdf_lineto() function draws a line from the current point to the point with coordinates (x-coor, y-coor).
The optional parameter mode determines the unit length. If it's 0 or omitted the default unit as specified for the page is used. Otherwise the coordinates are measured in postscript points disregarding the current unit.
See also cpdf_moveto(), cpdf_rmoveto(), cpdf_curveto().