gstreamer/gst-libs/gst/floatcast/floatcast.h

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/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
* Library <2002> Steve Baker <stevebaker_org@yahoo.co.uk>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:gstfloatcast
* @short_description: Floating point platform independence macros
*/
#ifndef __FLOATCAST_H__
#define __FLOATCAST_H__
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <string.h>
#include <glib/gtypes.h>
G_BEGIN_DECLS
#if (HAVE_LRINT && HAVE_LRINTF)
/* These defines enable functionality introduced with the 1999 ISO C
** standard. They must be defined before the inclusion of math.h to
** engage them. If optimisation is enabled, these functions will be
** inlined. With optimisation switched off, you have to link in the
** maths library using -lm.
*/
#define _ISOC9X_SOURCE 1
#define _ISOC99_SOURCE 1
#define __USE_ISOC9X 1
#define __USE_ISOC99 1
#include <math.h>
#define gst_cast_float(x) ((gint)lrintf(x))
#define gst_cast_double(x) ((gint)lrint(x))
#else
/* use a standard c cast, but do rounding correctly */
#define gst_cast_float(x) ((gint)floor((x)+0.5))
#define gst_cast_double(x) ((gint)floor((x)+0.5))
#endif
inline static gfloat
GFLOAT_SWAP_LE_BE(gfloat in)
{
union
{
guint32 i;
gfloat f;
} u;
u.f = in;
u.i = GUINT32_SWAP_LE_BE (u.i);
return u.f;
}
inline static gdouble
GDOUBLE_SWAP_LE_BE(gdouble in)
{
union
{
guint64 i;
gdouble d;
} u;
u.d = in;
u.i = GUINT64_SWAP_LE_BE (u.i);
return u.d;
}
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define GFLOAT_TO_LE(val) ((gfloat) (val))
#define GFLOAT_TO_BE(val) (GFLOAT_SWAP_LE_BE (val))
#define GDOUBLE_TO_LE(val) ((gdouble) (val))
#define GDOUBLE_TO_BE(val) (GDOUBLE_SWAP_LE_BE (val))
#elif G_BYTE_ORDER == G_BIG_ENDIAN
#define GFLOAT_TO_LE(val) (GFLOAT_SWAP_LE_BE (val))
#define GFLOAT_TO_BE(val) ((gfloat) (val))
#define GDOUBLE_TO_LE(val) (GDOUBLE_SWAP_LE_BE (val))
#define GDOUBLE_TO_BE(val) ((gdouble) (val))
#else /* !G_LITTLE_ENDIAN && !G_BIG_ENDIAN */
#error unknown ENDIAN type
#endif /* !G_LITTLE_ENDIAN && !G_BIG_ENDIAN */
#define GFLOAT_FROM_LE(val) (GFLOAT_TO_LE (val))
#define GFLOAT_FROM_BE(val) (GFLOAT_TO_BE (val))
#define GDOUBLE_FROM_LE(val) (GDOUBLE_TO_LE (val))
#define GDOUBLE_FROM_BE(val) (GDOUBLE_TO_BE (val))
G_END_DECLS
#endif /* __FLOATCAST_H__ */