endian.c

著名物理引擎Hawk的源代码

/* endian.c, HAWK game engine
 *
 * Copyright 1997-1998 by Phil Frisbie, Jr.
 * for Hawk Software
 *
 */

#include "hawk.h"
#include "internal.h"

#ifdef _SGI_SOURCE
#define	__BIG_ENDIAN__
#endif

#ifdef __BIG_ENDIAN__

short littleShort (short l)
{
	byte    b1,b2;

	b1 = l&255;
	b2 = (l>>8)&255;

	return (b1<<8) + b2;
}

short bigShort (short l)
{
	return l;
}


int littleLong (int l)
{
	byte    b1,b2,b3,b4;

	b1 = l&255;
	b2 = (l>>8)&255;
	b3 = (l>>16)&255;
	b4 = (l>>24)&255;

	return ((int)b1<<24) + ((int)b2<<16) + ((int)b3<<8) + b4;
}

int bigLong (int l)
{
	return l;
}


float littleFloat (float l)
{
	union {byte b[4]; float f;} in, out;
	
	in.f = l;
	out.b[0] = in.b[3];
	out.b[1] = in.b[2];
	out.b[2] = in.b[1];
	out.b[3] = in.b[0];
	
	return out.f;
}

float	bigFloat (float l)
{
	return l;
}


#else


short bigShort (short l)
{
	byte    b1,b2;

	b1 = l&255;
	b2 = (l>>8)&255;

	return (b1<<8) + b2;
}

short littleShort (short l)
{
	return l;
}


int bigLong (int l)
{
	byte    b1,b2,b3,b4;

	b1 = l&255;
	b2 = (l>>8)&255;
	b3 = (l>>16)&255;
	b4 = (l>>24)&255;

	return ((int)b1<<24) + ((int)b2<<16) + ((int)b3<<8) + b4;
}

int littleLong (int l)
{
	return l;
}

float bigFloat (float l)
{
	union {byte b[4]; float f;} in, out;
	
	in.f = l;
	out.b[0] = in.b[3];
	out.b[1] = in.b[2];
	out.b[2] = in.b[1];
	out.b[3] = in.b[0];
	
	return out.f;
}

float littleFloat (float l)
{
	return l;
}


#endif