/*
-----------------------------------------------------------------------------
This source file is part of OGRE
(Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2006 Torus Knot Software Ltd
Also see acknowledgements in Readme.html

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.

You may alternatively use this source under the terms of a specific version of
the OGRE Unrestricted License provided you have obtained such a license from
Torus Knot Software Ltd.
-----------------------------------------------------------------------------
*/
#include "OgreStableHeaders.h"
#include "OgreMatrix4.h"

#include "OgreVector3.h"
#include "OgreMatrix3.h"

namespace Ogre
{

    const Matrix4 Matrix4::ZERO(
        0, 0, 0, 0,
        0, 0, 0, 0,
        0, 0, 0, 0,
        0, 0, 0, 0 );

    const Matrix4 Matrix4::IDENTITY(
        1, 0, 0, 0,
        0, 1, 0, 0,
        0, 0, 1, 0,
        0, 0, 0, 1 );

    const Matrix4 Matrix4::CLIPSPACE2DTOIMAGESPACE(
        0.5,    0,  0, 0.5, 
          0, -0.5,  0, 0.5, 
          0,    0,  1,   0,
          0,    0,  0,   1);

    //-----------------------------------------------------------------------
    inline static Real
        MINOR(const Matrix4& m, const size_t r0, const size_t r1, const size_t r2, 
								const size_t c0, const size_t c1, const size_t c2)
    {
        return m[r0][c0] * (m[r1][c1] * m[r2][c2] - m[r2][c1] * m[r1][c2]) -
            m[r0][c1] * (m[r1][c0] * m[r2][c2] - m[r2][c0] * m[r1][c2]) +
            m[r0][c2] * (m[r1][c0] * m[r2][c1] - m[r2][c0] * m[r1][c1]);
    }
    //-----------------------------------------------------------------------
    Matrix4 Matrix4::adjoint() const
    {
        return Matrix4( MINOR(*this, 1, 2, 3, 1, 2, 3),
            -MINOR(*this, 0, 2, 3, 1, 2, 3),
            MINOR(*this, 0, 1, 3, 1, 2, 3),
            -MINOR(*this, 0, 1, 2, 1, 2, 3),

            -MINOR(*this, 1, 2, 3, 0, 2, 3),
            MINOR(*this, 0, 2, 3, 0, 2, 3),
            -MINOR(*this, 0, 1, 3, 0, 2, 3),
            MINOR(*this, 0, 1, 2, 0, 2, 3),

            MINOR(*this, 1, 2, 3, 0, 1, 3),
            -MINOR(*this, 0, 2, 3, 0, 1, 3),
            MINOR(*this, 0, 1, 3, 0, 1, 3),
            -MINOR(*this, 0, 1, 2, 0, 1, 3),

            -MINOR(*this, 1, 2, 3, 0, 1, 2),
            MINOR(*this, 0, 2, 3, 0, 1, 2),
            -MINOR(*this, 0, 1, 3, 0, 1, 2),
            MINOR(*this, 0, 1, 2, 0, 1, 2));
    }
    //-----------------------------------------------------------------------
    Real Matrix4::determinant() const
    {
        return m[0][0] * MINOR(*this, 1, 2, 3, 1, 2, 3) -
            m[0][1] * MINOR(*this, 1, 2, 3, 0, 2, 3) +
            m[0][2] * MINOR(*this, 1, 2, 3, 0, 1, 3) -
            m[0][3] * MINOR(*this, 1, 2, 3, 0, 1, 2);
    }
    //-----------------------------------------------------------------------
    Matrix4 Matrix4::inverse() const
    {
        Real m00 = m[0][0], m01 = m[0][1], m02 = m[0][2], m03 = m[0][3];
        Real m10 = m[1][0], m11 = m[1][1], m12 = m[1][2], m13 = m[1][3];
        Real m20 = m[2][0], m21 = m[2][1], m22 = m[2][2], m23 = m[2][3];
        Real m30 = m[3][0], m31 = m[3][1], m32 = m[3][2], m33 = m[3][3];

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

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

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

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

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

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

        Real d03 = - (v5 * m01 - v4 * m02 + v3 * m03) * invDet;
        Real d13 = + (v5 * m00 - v2 * m02 + v1 * m03) * invDet;
        Real d23 = - (v4 * m00 - v2 * m01 + v0 * m03) * invDet;
        Real 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
    {
        assert(isAffine());

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

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

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

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

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

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

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

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

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

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

        Real r03 = - (r00 * m03 + r01 * m13 + r02 * m23);
        Real r13 = - (r10 * m03 + r11 * m13 + r12 * m23);
        Real 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);
    }
    //-----------------------------------------------------------------------
    void Matrix4::makeTransform(const Vector3& position, const Vector3& scale, const Quaternion& orientation)
    {
        // Ordering:
        //    1. Scale
        //    2. Rotate
        //    3. Translate

        Matrix3 rot3x3, scale3x3;
        orientation.ToRotationMatrix(rot3x3);
        scale3x3 = Matrix3::ZERO;
        scale3x3[0][0] = scale.x;
        scale3x3[1][1] = scale.y;
        scale3x3[2][2] = scale.z;

        // Set up final matrix with scale, rotation and translation
        *this = rot3x3 * scale3x3;
        this->setTrans(position);

        // No projection term
        m[3][0] = 0; m[3][1] = 0; m[3][2] = 0; m[3][3] = 1;
    }
    //-----------------------------------------------------------------------
    void Matrix4::makeInverseTransform(const Vector3& position, const Vector3& scale, const Quaternion& orientation)
    {
        // Invert the parameters
        Vector3 invTranslate = -position;
        Vector3 invScale(1 / scale.x, 1 / scale.y, 1 / scale.z);
        Quaternion invRot = orientation.Inverse();

        // Because we're inverting, order is translation, rotation, scale
        // So make translation relative to scale & rotation
        invTranslate *= invScale; // scale
        invTranslate = invRot * invTranslate; // rotate

        // Next, make a 3x3 rotation matrix and apply inverse scale
        Matrix3 rot3x3, scale3x3;
        invRot.ToRotationMatrix(rot3x3);
        scale3x3 = Matrix3::ZERO;
        scale3x3[0][0] = invScale.x;
        scale3x3[1][1] = invScale.y;
        scale3x3[2][2] = invScale.z;

        // Set up final matrix with scale, rotation and translation
        *this = scale3x3 * rot3x3;
        this->setTrans(invTranslate);

        // No projection term
        m[3][0] = 0; m[3][1] = 0; m[3][2] = 0; m[3][3] = 1;
    }

}
