From:	Erik Max Francis <max AT alcyone DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Tank Movement
Date:	Tue, 06 Oct 1998 19:05:00 -0700
Organization:	Alcyone Systems
Lines:	19
Message-ID:	<361ACC4C.51090927@alcyone.com>
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

JEFF wrote:

> The atan() function can only return values between -90 and 90 degrees,
> which
> is two out of four quandrants. You need to check the signs of v1 and
> v2 to
> determine if the angle is between -180 and -90 or  between 90 and 180
> degrees and add or subtract 90 degrees accordingly.

Or just use atan2.  That's what it's for; no use reinventing the wheel.

-- 
Erik Max Francis / email max AT alcyone DOT com / whois mf303 / icq 16063900 
Alcyone Systems / irc maxxon (efnet) / finger max AT sade DOT alcyone DOT com
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           / H.L. Mencken

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