Path: utzoo!utgpu!watmath!clyde!att!pacbell!ames!ncar!gatech!hubcap!ncrcae!ncrlnk!uunet!mcvax!enea!kth!draken!tut!hydra!hylka!teittinen
From: teittinen@cc.helsinki.fi
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: Making balls move with TC 2.0 graphics, a tough problem HELP
Message-ID: <1270@cc.helsinki.fi>
Date: 10 Jan 89 14:59:04 GMT
References: <4343@freja.diku.dk>
Organization: University of Helsinki Computing Centre
Lines: 29

In article <4343@freja.diku.dk>, 
    viggo@freja.diku.dk (Allan Kim Schougaard) writes:

> Hello, I have been trying to make a Breakout game for the EGA with TC 2.0

Lot's of stuff deleted...

> 
> So I haven't found a way to get my ball moving both fast and flickerless.
> Will someone PLEASE HELP me: HOW IS IT DONE ? Isn't there an easy way ?
> 

You can try taking advantage of the 2 display pages EGA offers.
Draw the same background on both of the pages (you can change active
page using setactivepage-function). Then move the ball so that you draw
the ball to the page that is "hidden" i.e. not visual (use
setvisualpage). When the ball is drawn, you change the visual page and
draw the ball again to the other page which is now hidden, and so on.

Now your ball shouldn't flicker. To increase speed, increase the amount
of pixels to move the ball between page change.

-- 
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    EARN: teittinen@finuh          I "Studying is the only way to do nothing
Internet: teittinen@cc.helsinki.fi I  without anyone complaining about it." 
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             Marko Teittinen, student of computer science
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