sdl-ios-xcode: src/libm/s

annotate src/libm/s_cos.c @ 2866:e532417a6977

Fixed SDL 1.2 compatibility problem. The API specifies that SDL_OpenAudio() will fill out the 'desired' audio spec with the correct samples and size set by the driver. This value is important since it may be used by applications that size audio buffers, etc. However, we want to allow advanced applications to call SDL_OpenAudioDevice() which gets passed a const 'desired' parameter, and have the correct data filled into the 'obtained' parameter, possibly allowing or not allowing format changes. So... 'obtained' becomes the audio format the user callback is expected to use, and we add flags to allow the application to specify which format changes are allowed. Note: We really need to add a way to query the 'obtained' audio spec.

author	Sam Lantinga <slouken@libsdl.org>
date	Sat, 13 Dec 2008 06:36:47 +0000
parents	a98604b691c8
children	dc1eb82ffdaa

rev	line source
2756 a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	1 /* @(#)s_cos.c 5.1 93/09/24 */
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	2 /*
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	3 * ====================================================
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	5 *
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	6 * Developed at SunPro, a Sun Microsystems, Inc. business.
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	7 * Permission to use, copy, modify, and distribute this
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	8 * software is freely granted, provided that this notice
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	9 * is preserved.
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	10 * ====================================================
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	11 */
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	12
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	13 #if defined(LIBM_SCCS) && !defined(lint)
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	14 static char rcsid[] = "$NetBSD: s_cos.c,v 1.7 1995/05/10 20:47:02 jtc Exp $";
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	15 #endif
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	16
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	17 /* cos(x)
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	18 * Return cosine function of x.
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	19 *
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	20 * kernel function:
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	21 * __kernel_sin ... sine function on [-pi/4,pi/4]
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	22 * __kernel_cos ... cosine function on [-pi/4,pi/4]
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	23 * __ieee754_rem_pio2 ... argument reduction routine
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	24 *
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	25 * Method.
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	26 * Let S,C and T denote the sin, cos and tan respectively on
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	27 * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	28 * in [-pi/4 , +pi/4], and let n = k mod 4.
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	29 * We have
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	30 *
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	31 * n sin(x) cos(x) tan(x)
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	32 * ----------------------------------------------------------
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	33 * 0 S C T
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	34 * 1 C -S -1/T
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	35 * 2 -S -C T
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	36 * 3 -C S -1/T
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	37 * ----------------------------------------------------------
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	38 *
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	39 * Special cases:
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	40 * Let trig be any of sin, cos, or tan.
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	41 * trig(+-INF) is NaN, with signals;
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	42 * trig(NaN) is that NaN;
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	43 *
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	44 * Accuracy:
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	45 * TRIG(x) returns trig(x) nearly rounded
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	46 */
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	47
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	48 #include "math.h"
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	49 #include "math_private.h"
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	50
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	51 libm_hidden_proto(cos)
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	52 #ifdef __STDC__
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	53 double cos(double x)
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	54 #else
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	55 double cos(x)
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	56 double x;
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	57 #endif
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	58 {
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	59 double y[2], z = 0.0;
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	60 int32_t n, ix;
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	61
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	62 /* High word of x. */
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	63 GET_HIGH_WORD(ix, x);
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	64
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	65 /* \|x\| ~< pi/4 */
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	66 ix &= 0x7fffffff;
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	67 if (ix <= 0x3fe921fb)
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	68 return __kernel_cos(x, z);
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	69
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	70 /* cos(Inf or NaN) is NaN */
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	71 else if (ix >= 0x7ff00000)
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	72 return x - x;
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	73
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	74 /* argument reduction needed */
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	75 else {
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	76 n = __ieee754_rem_pio2(x, y);
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	77 switch (n & 3) {
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	78 case 0:
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	79 return __kernel_cos(y[0], y[1]);
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	80 case 1:
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	81 return -__kernel_sin(y[0], y[1], 1);
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	82 case 2:
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	83 return -__kernel_cos(y[0], y[1]);
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	84 default:
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	85 return __kernel_sin(y[0], y[1], 1);
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	86 }
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	87 }
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	88 }
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	89
a98604b691c8 Expanded the libm support and put it into a separate directory. Sam Lantinga <slouken@libsdl.org> parents: diff changeset	90 libm_hidden_def(cos)

Mercurial > sdl-ios-xcode

annotate src/libm/s_cos.c @ 2866:e532417a6977