🚀 go-pugleaf

In article <BxvJ3n.AI3@world.std.com>, grier@world.std.com (The Political Crony) writes:
|> I'm involved in a monitoring application where a number of meter-style
|> display glyphs will be updated from a comm channel coming in through
|> some Dispatch methods. All the updating per se seems to be fine. My
|> question pertains to update of the various displays as required.
|> 
|> It is possible for more than one meter to be updated at a time.  The
|> natural mechanism for forcing a display update would be to put a patch
|> around the meter and call the redraw() method. However, if more than
|> one such redraw() occurs on spots widely separated on the canvas, the
|> damage area will be the rectangle that contains all the damages,
|> causing unchanged areas to be redisplayed.
|> 
|> Is there some way to avoid the extra drawing without kludging in the
|> checking?

You can call redraw on the patch and then call repair on the window
to force an update.  This will cause an extra draw traversal, but less
actual drawing.