ifprinter.line (x1, y1)-(x2, y2) 0<x1<paperwidth, 0<x2<paperheight, 0<y1<paperheight, paperheight< 2* paperheight   ...
1: prineter.line (x1,y1)-((x2-x1)*(paperheight-y1)/(y2-y1),paperheight)
   ...
   printer.newdoc
2: prineter.line ((x2-x1)*(paperheight-y1)/(y2-y1),0)-((x2-x1)*(paperheight-y1)/(y2-y1),y2)
   ...
   printer.enddoc