[racket] Smoothing in 5.1.1 Racket Device Contexts (Ubuntu Lucid Lynx, Gnome)

At Thu, 30 Jun 2011 11:14:33 -0600, Matthew Flatt wrote:
> At Tue, 28 Jun 2011 19:43:13 -0400, "J. Vincent Toups" wrote:
> > Anyone else noticed that device contexts always smooth, regardless of
> > whether they are bitmap or canvas dcs and regardless of what you have
> > passed to the message `set-smoothing`.
> 
> The `draw-bitmap' method always smoothes when it scales. I don't think
> the underlying Cairo library gives us a way to turn off smoothing as it
> draws bitmaps. I'll double-check and, at a minimum, update the
> documentation.

After looking again, I think that setting the Cairo pattern filter to
CAIRO_FILTER_NEAREST is right 'unsmoothed mode, so I've made that
change for the next version.