diff options
Diffstat (limited to 'src/gui/math3d/qvector2d.cpp')
-rw-r--r-- | src/gui/math3d/qvector2d.cpp | 417 |
1 files changed, 417 insertions, 0 deletions
diff --git a/src/gui/math3d/qvector2d.cpp b/src/gui/math3d/qvector2d.cpp new file mode 100644 index 0000000..c3aaa42 --- /dev/null +++ b/src/gui/math3d/qvector2d.cpp @@ -0,0 +1,417 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Qt Software Information (qt-info@nokia.com) +** +** This file is part of the $MODULE$ of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain +** additional rights. These rights are described in the Nokia Qt LGPL +** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this +** package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3.0 as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU General Public License version 3.0 requirements will be +** met: http://www.gnu.org/copyleft/gpl.html. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at qt-sales@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qvector2d.h" +#include "qvector3d.h" +#include "qvector4d.h" +#include <QtCore/qdebug.h> +#include <QtCore/qmath.h> + +QT_BEGIN_NAMESPACE + +#ifndef QT_NO_VECTOR2D + +/*! + \class QVector2D + \brief The QVector2D class represents a vector or vertex in 2D space. + \since 4.6 + + The QVector2D class can also be used to represent vertices in 2D space. + We therefore do not need to provide a separate vertex class. + + The coordinates are stored internally using the most efficient + representation for the GL rendering engine, which will be either + floating-point or fixed-point. +*/ + +/*! + \fn QVector2D::QVector2D() + + Constructs a null vector, i.e. with coordinates (0, 0, 0). +*/ + +/*! + \fn QVector2D::QVector2D(qreal xpos, qreal ypos) + + Constructs a vector with coordinates (\a xpos, \a ypos). +*/ + +/*! + \fn QVector2D::QVector2D(const QPoint& point) + + Constructs a vector with x and y coordinates from a 2D \a point. +*/ + +/*! + \fn QVector2D::QVector2D(const QPointF& point) + + Constructs a vector with x and y coordinates from a 2D \a point. +*/ + +#ifndef QT_NO_VECTOR3D + +/*! + Constructs a vector with x and y coordinates from a 3D \a vector. + The z coordinate of \a vector is dropped. + + \sa toVector3D() +*/ +QVector2D::QVector2D(const QVector3D& vector) +{ + xp = vector.xp; + yp = vector.yp; +} + +#endif + +#ifndef QT_NO_VECTOR4D + +/*! + Constructs a vector with x and y coordinates from a 3D \a vector. + The z and w coordinates of \a vector are dropped. + + \sa toVector4D() +*/ +QVector2D::QVector2D(const QVector4D& vector) +{ + xp = vector.xp; + yp = vector.yp; +} + +#endif + +/*! + \fn bool QVector2D::isNull() const + + Returns true if the x and y coordinates are set to 0.0, + otherwise returns false. +*/ + +/*! + \fn qreal QVector2D::x() const + + Returns the x coordinate of this point. + + \sa setX(), y() +*/ + +/*! + \fn qreal QVector2D::y() const + + Returns the y coordinate of this point. + + \sa setY(), x() +*/ + +/*! + \fn void QVector2D::setX(qreal x) + + Sets the x coordinate of this point to the given \a x coordinate. + + \sa x(), setY() +*/ + +/*! + \fn void QVector2D::setY(qreal y) + + Sets the y coordinate of this point to the given \a y coordinate. + + \sa y(), setX() +*/ + +/*! + Returns the length of the vector from the origin. + + \sa lengthSquared(), normalized() +*/ +qreal QVector2D::length() const +{ + return qSqrt(xp * xp + yp * yp); +} + +/*! + Returns the squared length of the vector from the origin. + This is equivalent to the dot product of the vector with itself. + + \sa length(), dotProduct() +*/ +qreal QVector2D::lengthSquared() const +{ + return xp * xp + yp * yp; +} + +/*! + Returns the normalized unit vector form of this vector. + + If this vector is null, then a null vector is returned. If the length + of the vector is very close to 1, then the vector will be returned as-is. + Otherwise the normalized form of the vector of length 1 will be returned. + + \sa length(), normalize() +*/ +QVector2D QVector2D::normalized() const +{ + qreal len = lengthSquared(); + if (qFuzzyIsNull(len - 1.0f)) + return *this; + else if (!qFuzzyIsNull(len)) + return *this / qSqrt(len); + else + return QVector2D(); +} + +/*! + Normalizes the currect vector in place. Nothing happens if this + vector is a null vector or the length of the vector is very close to 1. + + \sa length(), normalized() +*/ +void QVector2D::normalize() +{ + qreal len = lengthSquared(); + if (qFuzzyIsNull(len - 1.0f) || qFuzzyIsNull(len)) + return; + + len = qSqrt(len); + + xp /= len; + yp /= len; +} + +/*! + \fn QVector2D &QVector2D::operator+=(const QVector2D &vector) + + Adds the given \a vector to this vector and returns a reference to + this vector. + + \sa operator-=() +*/ + +/*! + \fn QVector2D &QVector2D::operator-=(const QVector2D &vector) + + Subtracts the given \a vector from this vector and returns a reference to + this vector. + + \sa operator+=() +*/ + +/*! + \fn QVector2D &QVector2D::operator*=(qreal factor) + + Multiplies this vector's coordinates by the given \a factor, and + returns a reference to this vector. + + \sa operator/=() +*/ + +/*! + \fn QVector2D &QVector2D::operator*=(const QVector2D &vector) + + Multiplies the components of this vector by the corresponding + components in \a vector. +*/ + +/*! + \fn QVector2D &QVector2D::operator/=(qreal divisor) + + Divides this vector's coordinates by the given \a divisor, and + returns a reference to this vector. + + \sa operator*=() +*/ + +/*! + Returns the dot product of \a v1 and \a v2. +*/ +qreal QVector2D::dotProduct(const QVector2D& v1, const QVector2D& v2) +{ + return v1.xp * v2.xp + v1.yp * v2.yp; +} + +/*! + \fn bool operator==(const QVector2D &v1, const QVector2D &v2) + \relates QVector2D + + Returns true if \a v1 is equal to \a v2; otherwise returns false. + This operator uses an exact floating-point comparison. +*/ + +/*! + \fn bool operator!=(const QVector2D &v1, const QVector2D &v2) + \relates QVector2D + + Returns true if \a v1 is not equal to \a v2; otherwise returns false. + This operator uses an exact floating-point comparison. +*/ + +/*! + \fn const QVector2D operator+(const QVector2D &v1, const QVector2D &v2) + \relates QVector2D + + Returns a QVector2D object that is the sum of the given vectors, \a v1 + and \a v2; each component is added separately. + + \sa QVector2D::operator+=() +*/ + +/*! + \fn const QVector2D operator-(const QVector2D &v1, const QVector2D &v2) + \relates QVector2D + + Returns a QVector2D object that is formed by subtracting \a v2 from \a v1; + each component is subtracted separately. + + \sa QVector2D::operator-=() +*/ + +/*! + \fn const QVector2D operator*(qreal factor, const QVector2D &vector) + \relates QVector2D + + Returns a copy of the given \a vector, multiplied by the given \a factor. + + \sa QVector2D::operator*=() +*/ + +/*! + \fn const QVector2D operator*(const QVector2D &vector, qreal factor) + \relates QVector2D + + Returns a copy of the given \a vector, multiplied by the given \a factor. + + \sa QVector2D::operator*=() +*/ + +/*! + \fn const QVector2D operator*(const QVector2D &v1, const QVector2D &v2) + \relates QVector2D + + Multiplies the components of \a v1 by the corresponding + components in \a v2. +*/ + +/*! + \fn const QVector2D operator-(const QVector2D &vector) + \relates QVector2D + \overload + + Returns a QVector2D object that is formed by changing the sign of + the components of the given \a vector. + + Equivalent to \c {QVector2D(0,0) - vector}. +*/ + +/*! + \fn const QVector2D operator/(const QVector2D &vector, qreal divisor) + \relates QVector2D + + Returns the QVector2D object formed by dividing all three components of + the given \a vector by the given \a divisor. + + \sa QVector2D::operator/=() +*/ + +/*! + \fn bool qFuzzyCompare(const QVector2D& v1, const QVector2D& v2) + \relates QVector2D + + Returns true if \a v1 and \a v2 are equal, allowing for a small + fuzziness factor for floating-point comparisons; false otherwise. +*/ + +#ifndef QT_NO_VECTOR3D + +/*! + Returns the 3D form of this 2D vector, with the z coordinate set to zero. + + \sa toVector4D(), toPoint() +*/ +QVector3D QVector2D::toVector3D() const +{ + return QVector3D(xp, yp, 0.0f, 1); +} + +#endif + +#ifndef QT_NO_VECTOR4D + +/*! + Returns the 4D form of this 2D vector, with the z and w coordinates set to zero. + + \sa toVector3D(), toPoint() +*/ +QVector4D QVector2D::toVector4D() const +{ + return QVector4D(xp, yp, 0.0f, 0.0f, 1); +} + +#endif + +/*! + \fn QPoint QVector2D::toPoint() const + + Returns the QPoint form of this 2D vector. + + \sa toPointF(), toVector3D() +*/ + +/*! + \fn QPointF QVector2D::toPointF() const + + Returns the QPointF form of this 2D vector. + + \sa toPoint(), toVector3D() +*/ + +#ifndef QT_NO_DEBUG_STREAM + +QDebug operator<<(QDebug dbg, const QVector2D &vector) +{ + dbg.nospace() << "QVector2D(" << vector.x() << ", " << vector.y() << ')'; + return dbg.space(); +} + +#endif + +#endif + +QT_END_NAMESPACE |