Screen(‘DrawLine’, windowPtr [,color], fromH, fromV, toH, toV [,penWidth]);
Draw a line. “color” is the clut index (scalar or [r g b a] vector) that you
want to poke into each pixel; default produces black. “fromH” and “fromV” are
the starting x and y positions, respectively. “toH” and “toV” are the ending x
and y positions, respectively. Default “penWidth” is 1.
###See also: DrawLines