kc3-lang/SDL/src/libm/s_sin.c

• Show log

  Commit

• Hash : 24c86b55
  Author :
  Date : 2014-09-11T19:24:42
  

  [X11] Reconcile logical keyboard state with physical state on FocusIn since the window system doesn't do it for us like other platforms. This prevents sticky keys and missed keys when going in and out of focus, for example Alt would appear to stick if switching away from an SDL app with Alt-Tab and had to be pressed again. CR: Sam

Download

• src/libm/s_sin.c

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

Download