View.Set("graphics:max,max")

proc drawtriangle (x1, y1, x2, y2, x3, y3, c : int)
    drawline (x1, y1, x2, y2, c)
    drawline (x1, y1, x3, y3, c)
    drawline (x3, y3, x2, y2, c)
end drawtriangle

drawtriangle (100, 100, 400, 400, 600, 200, blue)