tlhiv wrote:
> Dan,
>
> Thanks for those kind words. The point (independent of this particular
> drawing) is that it should be pretty straightforward to change the
> default background of a figure. MetaPost uses "background" to apply to
> "unfill" and "undraw" only. There should be a way to tell MetaPost ...
> "from this point forward, everything drawn should be of color <x,y,z>
> sitting on top of a background of color <u,v,w>".
Metapost probably doesn't have a way to do this because there is no
such concept in Postscript as a "background". There is only has the sum
total of what has already been drawn, and any paths or fills or texts
are added on top of that. That is why, if you want a picture drawn on a
colored background, you need to paint that background and then put
everything else on top of it.
Thus Metapost plain.mp allows a color "background' to be assigned, but
it is up to the user, if he wants the entire picture on a rectangle of
this color, to unfill that rectangle before laying the picture over it.
Dan