Re: ncurses refresh() efficiency

[Thomas Dickey]

On Thu, 20 Nov 2003, Tom Sargent wrote:

> Hello:
>       I am using ncurses in a control program.  I am curious about the
> refresh() fcn.  Does it only redraw the characters that changed since
> the last refresh(), or does it redraw the whole screen?

technically neither: it redraws the characters that changed, but those may
constitute regions on the screen that are close enough that that few
intervening characters will also be repainted.

The whole screen would be redrawn if the application told ncurses to touch
the whole screen, e.g., using touchwin or touchline, or if it called
clearok().

-- 
Thomas E. Dickey
http://invisible-island.net
ftp://invisible-island.net