/*
 Copyright (C) 2011 by Ivan Safrin
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
 
 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
*/

#include "PolyMatrix4.h"

using namespace Polycode;

Matrix4::Matrix4() {
	identity();
}

Matrix4::~Matrix4() {

}

Matrix4::Matrix4(const Number *m) {
	memcpy(ml, m, sizeof(Number)*16);
}

	Matrix4 Matrix4::inverse() const
    {
        Number m00 = m[0][0], m01 = m[0][1], m02 = m[0][2], m03 = m[0][3];
        Number m10 = m[1][0], m11 = m[1][1], m12 = m[1][2], m13 = m[1][3];
        Number m20 = m[2][0], m21 = m[2][1], m22 = m[2][2], m23 = m[2][3];
        Number m30 = m[3][0], m31 = m[3][1], m32 = m[3][2], m33 = m[3][3];

        Number v0 = m20 * m31 - m21 * m30;
        Number v1 = m20 * m32 - m22 * m30;
        Number v2 = m20 * m33 - m23 * m30;
        Number v3 = m21 * m32 - m22 * m31;
        Number v4 = m21 * m33 - m23 * m31;
        Number v5 = m22 * m33 - m23 * m32;

        Number t00 = + (v5 * m11 - v4 * m12 + v3 * m13);
        Number t10 = - (v5 * m10 - v2 * m12 + v1 * m13);
        Number t20 = + (v4 * m10 - v2 * m11 + v0 * m13);
        Number t30 = - (v3 * m10 - v1 * m11 + v0 * m12);

        Number invDet = 1 / (t00 * m00 + t10 * m01 + t20 * m02 + t30 * m03);

        Number d00 = t00 * invDet;
        Number d10 = t10 * invDet;
        Number d20 = t20 * invDet;
        Number d30 = t30 * invDet;

        Number d01 = - (v5 * m01 - v4 * m02 + v3 * m03) * invDet;
        Number d11 = + (v5 * m00 - v2 * m02 + v1 * m03) * invDet;
        Number d21 = - (v4 * m00 - v2 * m01 + v0 * m03) * invDet;
        Number d31 = + (v3 * m00 - v1 * m01 + v0 * m02) * invDet;

        v0 = m10 * m31 - m11 * m30;
        v1 = m10 * m32 - m12 * m30;
        v2 = m10 * m33 - m13 * m30;
        v3 = m11 * m32 - m12 * m31;
        v4 = m11 * m33 - m13 * m31;
        v5 = m12 * m33 - m13 * m32;

        Number d02 = + (v5 * m01 - v4 * m02 + v3 * m03) * invDet;
        Number d12 = - (v5 * m00 - v2 * m02 + v1 * m03) * invDet;
        Number d22 = + (v4 * m00 - v2 * m01 + v0 * m03) * invDet;
        Number d32 = - (v3 * m00 - v1 * m01 + v0 * m02) * invDet;

        v0 = m21 * m10 - m20 * m11;
        v1 = m22 * m10 - m20 * m12;
        v2 = m23 * m10 - m20 * m13;
        v3 = m22 * m11 - m21 * m12;
        v4 = m23 * m11 - m21 * m13;
        v5 = m23 * m12 - m22 * m13;

        Number d03 = - (v5 * m01 - v4 * m02 + v3 * m03) * invDet;
        Number d13 = + (v5 * m00 - v2 * m02 + v1 * m03) * invDet;
        Number d23 = - (v4 * m00 - v2 * m01 + v0 * m03) * invDet;
        Number d33 = + (v3 * m00 - v1 * m01 + v0 * m02) * invDet;

        return Matrix4(
            d00, d01, d02, d03,
            d10, d11, d12, d13,
            d20, d21, d22, d23,
            d30, d31, d32, d33);
    }
    //-----------------------------------------------------------------------
	Matrix4 Matrix4::inverseAffine(void) const
    {

        Number m10 = m[1][0], m11 = m[1][1], m12 = m[1][2];
        Number m20 = m[2][0], m21 = m[2][1], m22 = m[2][2];

        Number t00 = m22 * m11 - m21 * m12;
        Number t10 = m20 * m12 - m22 * m10;
        Number t20 = m21 * m10 - m20 * m11;

        Number m00 = m[0][0], m01 = m[0][1], m02 = m[0][2];

        Number invDet = 1 / (m00 * t00 + m01 * t10 + m02 * t20);

        t00 *= invDet; t10 *= invDet; t20 *= invDet;

        m00 *= invDet; m01 *= invDet; m02 *= invDet;

        Number r00 = t00;
        Number r01 = m02 * m21 - m01 * m22;
        Number r02 = m01 * m12 - m02 * m11;

        Number r10 = t10;
        Number r11 = m00 * m22 - m02 * m20;
        Number r12 = m02 * m10 - m00 * m12;

        Number r20 = t20;
        Number r21 = m01 * m20 - m00 * m21;
        Number r22 = m00 * m11 - m01 * m10;

        Number m03 = m[0][3], m13 = m[1][3], m23 = m[2][3];

        Number r03 = - (r00 * m03 + r01 * m13 + r02 * m23);
        Number r13 = - (r10 * m03 + r11 * m13 + r12 * m23);
        Number r23 = - (r20 * m03 + r21 * m13 + r22 * m23);

        return Matrix4(
            r00, r01, r02, r03,
            r10, r11, r12, r13,
            r20, r21, r22, r23,
              0,   0,   0,   1);
    }