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70438be272
WinRT apps can set a default, preferred orientation via a .appxmanifest file. SDL was overriding this on app startup, and making the app use all possible orientations (landscape and portrait). Thanks to Eric Wing for the heads up on this!
92 lines
2.3 KiB
C
92 lines
2.3 KiB
C
/* @(#)s_sin.c 5.1 93/09/24 */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunPro, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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#if defined(LIBM_SCCS) && !defined(lint)
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static const char rcsid[] =
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"$NetBSD: s_sin.c,v 1.7 1995/05/10 20:48:15 jtc Exp $";
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#endif
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/* sin(x)
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* Return sine function of x.
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*
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* kernel function:
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* __kernel_sin ... sine function on [-pi/4,pi/4]
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* __kernel_cos ... cose function on [-pi/4,pi/4]
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* __ieee754_rem_pio2 ... argument reduction routine
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*
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* Method.
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* Let S,C and T denote the sin, cos and tan respectively on
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* [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
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* in [-pi/4 , +pi/4], and let n = k mod 4.
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* We have
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*
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* n sin(x) cos(x) tan(x)
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* ----------------------------------------------------------
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* 0 S C T
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* 1 C -S -1/T
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* 2 -S -C T
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* 3 -C S -1/T
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* ----------------------------------------------------------
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*
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* Special cases:
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* Let trig be any of sin, cos, or tan.
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* trig(+-INF) is NaN, with signals;
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* trig(NaN) is that NaN;
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*
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* Accuracy:
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* TRIG(x) returns trig(x) nearly rounded
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*/
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#include "math_libm.h"
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#include "math_private.h"
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libm_hidden_proto(sin)
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#ifdef __STDC__
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double sin(double x)
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#else
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double sin(x)
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double x;
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#endif
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{
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double y[2], z = 0.0;
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int32_t n, ix;
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/* High word of x. */
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GET_HIGH_WORD(ix, x);
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/* |x| ~< pi/4 */
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ix &= 0x7fffffff;
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if (ix <= 0x3fe921fb)
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return __kernel_sin(x, z, 0);
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/* sin(Inf or NaN) is NaN */
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else if (ix >= 0x7ff00000)
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return x - x;
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/* argument reduction needed */
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else {
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n = __ieee754_rem_pio2(x, y);
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switch (n & 3) {
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case 0:
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return __kernel_sin(y[0], y[1], 1);
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case 1:
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return __kernel_cos(y[0], y[1]);
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case 2:
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return -__kernel_sin(y[0], y[1], 1);
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default:
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return -__kernel_cos(y[0], y[1]);
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}
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}
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}
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libm_hidden_def(sin)
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