mtxutil.c 1.64 KB
/**************************************************************************
 *									  *
 *		 Copyright (C) 1994, Silicon Graphics, Inc.		  *
 *									  *
 *  These coded instructions, statements, and computer programs  contain  *
 *  unpublished  proprietary  information of Silicon Graphics, Inc., and  *
 *  are protected by Federal copyright law.  They  may  not be disclosed  *
 *  to  third  parties  or copied or duplicated in any form, in whole or  *
 *  in part, without the prior written consent of Silicon Graphics, Inc.  *
 *									  *
 **************************************************************************/

#include "guint.h"

void guMtxF2L(float mf[4][4], Mtx *m)
{
	int	i, j;
	int	e1,e2;
	int	*ai,*af;


	ai=(int *) &m->m[0][0];
	af=(int *) &m->m[2][0];

	for (i=0; i<4; i++)
	for (j=0; j<2; j++) {
		e1=FTOFIX32(mf[i][j*2]);
		e2=FTOFIX32(mf[i][j*2+1]);
		*(ai++) = ( e1 & 0xffff0000 ) | ((e2 >> 16)&0xffff);
		*(af++) = ((e1 << 16) & 0xffff0000) | (e2 & 0xffff);
	}
}

void guMtxL2F(float mf[4][4], Mtx *m)
{
	int		i, j;
	unsigned int	e1,e2;
	unsigned int	*ai,*af;
	int		q1,q2;

	ai=(unsigned int *) &m->m[0][0];
	af=(unsigned int *) &m->m[2][0];

	for (i=0; i<4; i++)
	for (j=0; j<2; j++) {
		e1 = (*ai & 0xffff0000) | ((*af >> 16) & 0xffff);
		e2 = ((*(ai++) << 16) & 0xffff0000) | (*(af++) & 0xffff);
		q1 = *((int *)&e1); 
		q2 = *((int *)&e2); 

		mf[i][j*2] = FIX32TOF(q1);
		mf[i][j*2+1] = FIX32TOF(q2);
	}
}

void guMtxIdentF(float mf[4][4])
{
	int	i, j;

	for (i=0; i<4; i++)
	for (j=0; j<4; j++)
		if (i == j) mf[i][j] = 1.0;
		else mf[i][j] = 0.0;
}

void guMtxIdent(Mtx *m)
{
        float	mf[4][4];

	guMtxIdentF(mf);

	guMtxF2L(mf, m);
}