[comp.windows.x] Can X windows flash?

mouse@LARRY.MCRCIM.MCGILL.EDU (der Mouse) (05/02/90)

> Looking through the X windows documentation I can see nothing about
> how to make pixels or characters flash.  Is this not possible on an X
> window server?

The core protocol does not provide any direct support for this, as far
as I can tell.  It would, of course, be possible for a server to define
extra semantics for, say, an extra bitplane, to be a blink-enable plane
or some such.  (Wouldn't it?  I see nothing wrong with it, but what do
I know...)

I also did a terminal emulator that supported flashing text; the client
simply drew the text in the two ways alternately.  Not especially
clean, perhaps, and it wouldn't work too well over a slow connection,
but for the desired application it worked fine.

					der Mouse

			old: mcgill-vision!mouse
			new: mouse@larry.mcrcim.mcgill.edu

tiwary@nwnexus.WA.COM (Ashutosh Tiwary) (05/09/90)

In article <9005021529.AA04050@Larry.McRCIM.McGill.EDU> mouse@LARRY.MCRCIM.MCGILL.EDU (der Mouse) writes:
>> Looking through the X windows documentation I can see nothing about
>> how to make pixels or characters flash.  Is this not possible on an X
>> window server?
>
One thing that I have seen done is to have a process running in the background
which causes blinking by replacing the color in a given color table entry with
another to create the illusion of flashing. The main draw back of this idea is
that now all the places where the given color table entry is used, the content
will flash. The way around that is to allocate say red and "blinking-red".
This also is quite wasteful of the color map.

Hope this helps.

- Ashutosh Tiwary
tiwary@nwnexus.wa.com

ben@hpcvlx.cv.hp.com (Benjamin Ellsworth) (05/10/90)

> One thing that I have seen done is to have a process running in the 
> background which causes blinking by replacing the color in a given 
> color table entry with another to create the illusion of flashing.

This works ok.

> The main draw back of this idea is that now all the places where the 
> given color table entry is used, the content will flash.

I think that the main drawback is that the rate of flash is not
constant.  Hardware blinks at a rock solid rate.  Software driven
blinking will depend on when the request actually gets serviced.  On
busy machines it gets really annoying.

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