/* Copyright (C) 2009 Wildfire Games.
 * This file is part of 0 A.D.
 *
 * 0 A.D. is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * 0 A.D. 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
 */

/**** Decompose.h - Basic declarations ****/
#ifndef INCLUDED_DECOMPOSE
#define INCLUDED_DECOMPOSE
typedef struct {float x, y, z, w;} Quat; /* Quaternion */
enum QuatPart {X, Y, Z, W};
typedef Quat HVect; /* Homogeneous 3D vector */
typedef float HMatrix[4][4]; /* Right-handed, for column vectors */
typedef struct {
    HVect t;	/* Translation components */
    Quat  q;	/* Essential rotation	  */
    Quat  u;	/* Stretch rotation	  */
    HVect k;	/* Stretch factors	  */
    float f;	/* Sign of determinant	  */
} AffineParts;
float polar_decomp(HMatrix M, HMatrix Q, HMatrix S);
HVect spect_decomp(HMatrix S, HMatrix U);
Quat snuggle(Quat q, HVect *k);
void decomp_affine(HMatrix A, AffineParts *parts);
void invert_affine(AffineParts *parts, AffineParts *inverse);
#endif