M. Adam Davis wrote:

> I did this a -long- time ago, and the general idea of the particular
> method was:

> for count = x1 to x2  (this is the greater distance to travel, by
> going on it, we won't miss any pixels on the line, nor draw any extra
> pixels.)

  Ah, but there's the trick.  If you use only this method, you get a
somewhat scruffy line.  Thus:

         XXX
            XXX
               XXX
                  XXX

  You actually WANT to draw the "extra" pixels.

  As I recall it (it's in a book I have here somewhere, rather old but
the fact of the matter is there is almost nothing new, no grand
discoveries in recent times - like compression techniques, there are NO
new ones being discovered!), the Bresenham (if that is the one)
algorithm determines at each point whether to make an X or a Y step but
not both, resulting in a much more satisfactory line thus:

         XXXX
            XXXX
               XXXX
                  XXXX
--
  Cheers,
        Paul B.