From:	Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Allegro mouse blinking
Date:	Sun, 13 Jul 1997 17:36:31 +0100
Organization:	None
Distribution:	world
Message-ID:	<C18TpIAPQQyzEwme@talula.demon.co.uk>
References:	<01bc8df3$a40399c0$0100007f AT majka>
NNTP-Posting-Host:	talula.demon.co.uk
MIME-Version:	1.0
Lines:	29
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Marián Dvorský writes:
>Before every write to screen i have to turn off mouse cursor and after
>write turn on. But mouse cursor is blinking when i make many accesses
>to video memory !! 

This problem comes up quite frequently: if you search the mail archives
on www.delorie.com for "Allegro" and "mouse" you should find seveal
posts about how to avoid mouse flicker...

>Can I change mouse_buffer (if exists something like that)
>where is written background of mouse cursor, something what is under 
>this cursor. Can I change it and write there "NEW" background (i know 
>what will be there; under it). 

You could try that (change mouse.c to make the ms bitmap externally
visible), but it would be very complicated to get right, and I don't
think it would work too well.

If you are doing double buffered drawing, tell Allegro to put the mouse
pointer on your memory buffer rather than the physical screen, and the
flicker will go away. Alternatively you can use the freeze_mouse_flag to
prevent the mouse moving during your screen update, and only hide it if
the area you are about to redraw overlaps with the current mouse
position...


--
Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
Beauty is a French phonetic corruption of a short cloth neck ornament.

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