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/**************************************************************************
* *
* Copyright (C) 1994, Silicon Graphics, Inc. *
* *
* These coded instructions, statements, and computer programs contain *
* unpublished proprietary information of Silicon Graphics, Inc., and *
* are protected by Federal copyright law. They may not be disclosed *
* to third parties or copied or duplicated in any form, in whole or *
* in part, without the prior written consent of Silicon Graphics, Inc. *
* *
**************************************************************************/
#include "guint.h"
/* ====================================================================
* ====================================================================
*
* Module: sins.c
* $Revision: 1.3 $
* $Date: 1998/10/09 06:15:00 $
* $Author: has $
* $Source: /exdisk2/cvs/N64OS/Master/cvsmdev2/PR/libultra/monegi/gu/sins.c,v $
*
* ====================================================================
* ====================================================================
*/
/* coefficients for polynomial approximation of sin on +/- pi/2 */
/* ====================================================================
*
* FunctionName sins
*
* Description computes sine of arg
*
* ====================================================================
*/
#include "sintable.h"
signed short
sins( unsigned short x )
{
/* 0 <= x < 0x10000 ==> 0 <= x < 2PI */
signed short val;
x >>= 4; /* Now range 0 <= x < 0x1000 */
if (x & 0x400) {
val = sintable[0x3ff - (x & 0x3ff)];
} else {
val = sintable[x & 0x3ff];
}
if (x & 0x800) {
return -val;
} else {
return val;
}
}
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