line_paper takes two mandatory arguments and two optional arguments.
xspacing, the spacing in the x direction.
θ, the angle from the horizontal to draw the lines.
Optionally, x=xmin..xmax, to determine how
far the lines extend in the x direction (by default, the
distances given in the graphic configuration page accessible from
the main menu).
Optionally, y=ymin..ymax, to determine how
far the lines extend in the y direction (by default, the
distances given in the graphic configuration page accessible from
the main menu).
line_paper(xspacing,θ ⟨,x=xmin..xmax,y=ymin..ymax ⟩)
draws lined paper.