magnum/src/Math/Matrix4.h

#ifndef Magnum_Math_Matrix4_h
#define Magnum_Math_Matrix4_h
/*
    Copyright © 2010, 2011, 2012 Vladimír Vondruš <mosra@centrum.cz>

    This file is part of Magnum.

    Magnum is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License version 3
    only, as published by the Free Software Foundation.

    Magnum 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 version 3 for more details.
*/

/** @file
 * @brief Class Magnum::Math::Matrix4
 */

#include "Matrix3.h"
#include "Vector4.h"

namespace Magnum { namespace Math {

/**
 * @brief 4x4 matrix
 *
 * @todo Rotation with Euler angles
 * @todo Shearing
 * @todo Reflection
 */
template<class T> class Matrix4: public Matrix<T, 4> {
    public:
        /** @copydoc Matrix::from(T*) */
        inline constexpr static Matrix4<T>& from(T* data) {
            return *reinterpret_cast<Matrix4<T>*>(data);
        }

        /** @copydoc Matrix::from(const T*) */
        inline constexpr static const Matrix4<T>& from(const T* data) {
            return *reinterpret_cast<const Matrix4<T>*>(data);
        }

        /** @copydoc Matrix::from(const Vector<T, size>&, const U&...) */
        template<class ...U> inline constexpr static Matrix4<T> from(const Vector<T, 4>& first, const U&... next) {
            return Matrix<T, 4>::from(first, next...);
        }

        /**
         * @brief Translation matrix
         * @param vec   Translation vector
         */
        static constexpr Matrix4<T> translation(const Vector3<T>& vec) {
            return Matrix4( /* Column-major! */
                1.0f, 0.0f, 0.0f, 0.0f,
                0.0f, 1.0f, 0.0f, 0.0f,
                0.0f, 0.0f, 1.0f, 0.0f,
                vec.x(), vec.y(), vec.z(), 1.0f
            );
        }

        /**
         * @brief Scaling matrix
         * @param vec   Scaling vector
         */
        static constexpr Matrix4 scaling(const Vector3<T>& vec) {
            return Matrix4( /* Column-major! */
                vec.x(), 0.0f, 0.0f, 0.0f,
                0.0f, vec.y(), 0.0f, 0.0f,
                0.0f, 0.0f, vec.z(), 0.0f,
                0.0f, 0.0f, 0.0f, 1.0f
            );
        }

        /**
         * @brief Rotation matrix
         * @param angle Rotation angle (counterclockwise, in radians)
         * @param vec   Rotation vector
         */
        static Matrix4 rotation(T angle, const Vector3<T>& vec) {
            Vector3<T> vn = vec.normalized();

            T sine = sin(angle);
            T cosine = cos(angle);
            T oneMinusCosine = T(1) - cosine;

            T xx = vn.x()*vn.x();
            T xy = vn.x()*vn.y();
            T xz = vn.x()*vn.z();
            T yy = vn.y()*vn.y();
            T yz = vn.y()*vn.z();
            T zz = vn.z()*vn.z();

            return Matrix4( /* Column-major! */
                cosine + xx*oneMinusCosine,
                    xy*oneMinusCosine + vn.z()*sine,
                        xz*oneMinusCosine - vn.y()*sine,
                           T(0),
                xy*oneMinusCosine - vn.z()*sine,
                    cosine + yy*oneMinusCosine,
                        yz*oneMinusCosine + vn.x()*sine,
                           T(0),
                xz*oneMinusCosine + vn.y()*sine,
                    yz*oneMinusCosine - vn.x()*sine,
                        cosine + zz*oneMinusCosine,
                           T(0),
                T(0), T(0), T(0), T(1)
            );
        }

        /** @copydoc Matrix::Matrix(ZeroType) */
        inline constexpr explicit Matrix4(typename Matrix<T, 4>::ZeroType): Matrix<T, 3>(Matrix<T, 3>::Zero) {}

        /** @copydoc Matrix::Matrix(IdentityType) */
        inline constexpr explicit Matrix4(typename Matrix<T, 4>::IdentityType = Matrix<T, 4>::Identity, T value = T(1)): Matrix<T, 4>{
            /** @todo Make this in Matrix itself, after it will be constexpr */
            value, 0.0f, 0.0f, 0.0f,
            0.0f, value, 0.0f, 0.0f,
            0.0f, 0.0f, value, 0.0f,
            0.0f, 0.0f, 0.0f, value
        } {}

        #ifndef DOXYGEN_GENERATING_OUTPUT
        template<class U> explicit Matrix4(U) = delete;
        #endif

        /** @copydoc Matrix::Matrix(T, U...) */
        #ifndef DOXYGEN_GENERATING_OUTPUT
        template<class ...U> inline constexpr Matrix4(T first, U... next): Matrix<T, 4>(first, next...) {}
        #else
        template<class ...U> inline constexpr Matrix4(T first, U... next) {}
        #endif

        /** @copydoc Matrix::Matrix(const Matrix<T, size>&) */
        inline constexpr Matrix4(const Matrix<T, 4>& other): Matrix<T, 4>(other) {}

        /** @copydoc Matrix::operator=() */
        inline Matrix4<T>& operator=(const Matrix<T, 4>& other) {
            Matrix<T, 4>::operator=(other);
            return *this;
        }

        /** @copydoc Matrix::operator[](size_t) */
        inline Vector4<T>& operator[](size_t col) { return Vector4<T>::from(Matrix<T, 4>::data()+col*4); }

        /** @copydoc Matrix::operator[](size_t) const */
        inline constexpr const Vector4<T>& operator[](size_t col) const { return Vector4<T>::from(Matrix<T, 4>::data()+col*4); }

        /** @copydoc Matrix::operator*(const Matrix<T, size>&) const */
        inline Matrix4<T> operator*(const Matrix<T, 4>& other) const { return Matrix<T, 4>::operator*(other); }

        /** @copydoc Matrix::operator*=() */
        inline Matrix4<T>& operator*=(const Matrix<T, 4>& other) {
            Matrix<T, 4>::operator*=(other);
            return *this;
        }

        /** @copydoc Matrix::operator*(const Vector<T, size>&) const */
        inline Vector4<T> operator*(const Vector<T, 4>& other) const { return Matrix<T, 4>::operator*(other); }

        /** @copydoc Matrix::transposed() */
        inline Matrix4<T> transposed() const { return Matrix<T, 4>::transposed(); }

        /** @copydoc Matrix::ij() */
        inline Matrix3<T> ij(size_t skipRow, size_t skipCol) const { return Matrix<T, 4>::ij(skipRow, skipCol); }

        /** @copydoc Matrix::inversed() */
        inline Matrix4<T> inversed() const { return Matrix<T, 4>::inversed(); }

        /** @brief Rotation part of the matrix */
        inline Matrix3<T> rotation() const {
            return Matrix3<T>::from(
                (*this)[0].xyz().normalized(),
                (*this)[1].xyz().normalized(),
                (*this)[2].xyz().normalized());
        }
};

#ifndef DOXYGEN_GENERATING_OUTPUT
template<class T> Corrade::Utility::Debug operator<<(Corrade::Utility::Debug debug, const Magnum::Math::Matrix4<T>& value) {
    return debug << static_cast<const Magnum::Math::Matrix<T, 4>&>(value);
}
#endif

}}

#endif