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Mail Archives: djgpp/1999/03/14/20:30:37

Message-ID: <36EBFD7D.7D0FCB2C@geocities.com>
From: The Beyonder <beyonder69 AT geocities DOT com>
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Newsgroups: comp.os.msdos.djgpp
Subject: sin(acos((float)i/1024))*0x10000L
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Date: Sun, 14 Mar 1999 13:18:37 -0500
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

Hi Y'all,
after visiting a site on how to draw primitive shapes to the screen, I
decided to try this circle technique.  It said to first generate a
trigonomitry table full of sin_acos info?  So I copied his source code:

<BEGIN SOURCE CODE>
long table[1024];

printf( "Generating Trigonomitry table..." );
fflush( stdout ); // So that it writes it to the screen
for (int i=0;i<1024;i++) {
	table[i]=sin(acos((float)i/1024))*0x10000L;
					// Whats this part for?
}
printf( "Done\n" );

</END SOURCE CODE>

the tutorial said that he's using fixed point math, instead of floating
point for faster circles.

After compilation, I get 1 warning:  cast from 'long int' to 'double'.
I ignore this...

Now during compilation it just gets stuck on "Generating Tri table...". 
SIN alone works, and so does COS... but ACOS alone just stalls (I can
quit using CTRL-C).

Is it ACOS or my programming?

NOTE: my computer does not have an FPU unit, but I waited for the thing
for nearly 10 MINS, and it still didn't do anything...
-- 
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