内容

• 公共函数
• 静态公共成员
• 相关非成员
• 详细描述

QVector3D 类

The QVector3D class represents a vector or vertex in 3D space. 更多...

头：	#include <QVector3D>
Since:	Qt 4.6

• 所有成员列表，包括继承成员

公共函数

	QVector3D ()
	QVector3D (qreal xpos , qreal ypos , qreal zpos )
	QVector3D (const QPoint & point )
	QVector3D (const QPointF & point )
	QVector3D (const QVector2D & vector )
	QVector3D (const QVector2D & vector , qreal zpos )
	QVector3D (const QVector4D & vector )
qreal	distanceToLine (const QVector3D & point , const QVector3D & direction ) const
qreal	distanceToPlane (const QVector3D & plane , const QVector3D & normal ) const
qreal	distanceToPlane (const QVector3D & plane1 , const QVector3D & plane2 , const QVector3D & plane3 ) const
bool	isNull () const
qreal	length () const
qreal	lengthSquared () const
void	normalize ()
QVector3D	normalized () const
void	setX (qreal x )
void	setY (qreal y )
void	setZ (qreal z )
QPoint	toPoint () const
QPointF	toPointF () const
QVector2D	toVector2D () const
QVector4D	toVector4D () const
qreal	x () const
qreal	y () const
qreal	z () const
	operator QVariant () const
QVector3D &	operator*= (qreal factor )
QVector3D &	operator*= (const QVector3D & vector )
QVector3D &	operator+= (const QVector3D & vector )
QVector3D &	operator-= (const QVector3D & vector )
QVector3D &	operator/= (qreal divisor )

静态公共成员

QVector3D	crossProduct (const QVector3D & v1 , const QVector3D & v2 )
qreal	dotProduct (const QVector3D & v1 , const QVector3D & v2 )
QVector3D	normal (const QVector3D & v1 , const QVector3D & v2 )
QVector3D	normal (const QVector3D & v1 , const QVector3D & v2 , const QVector3D & v3 )

相关非成员

bool	qFuzzyCompare (const QVector3D & v1 , const QVector3D & v2 )
bool	operator!= (const QVector3D & v1 , const QVector3D & v2 )
const QVector3D	operator* (qreal factor , const QVector3D & vector )
const QVector3D	operator* (const QVector3D & vector , qreal factor )
const QVector3D	operator* (const QVector3D & v1 , const QVector3D & v2 )
const QVector3D	operator+ (const QVector3D & v1 , const QVector3D & v2 )
const QVector3D	operator- (const QVector3D & v1 , const QVector3D & v2 )
const QVector3D	operator- (const QVector3D & vector )
const QVector3D	operator/ (const QVector3D & vector , qreal divisor )
QDataStream &	operator<< (QDataStream & stream , const QVector3D & vector )
bool	operator== (const QVector3D & v1 , const QVector3D & v2 )
QDataStream &	operator>> (QDataStream & stream , QVector3D & vector )

详细描述

The QVector3D class represents a vector or vertex in 3D space.

Vectors are one of the main building blocks of 3D representation and drawing. They consist of three coordinates, traditionally called x, y, and z.

The QVector3D class can also be used to represent vertices in 3D space. We therefore do not need to provide a separate vertex class.

注意： By design values in the QVector3D instance are stored as float . This means that on platforms where the qreal arguments to QVector3D functions are represented by double values, it is possible to lose precision.

另请参阅 QVector2D , QVector4D ，和 QQuaternion .

成员函数文档编制

QVector3D:: QVector3D ()

构造 null 向量，即：采用坐标 (0, 0, 0)。

QVector3D:: QVector3D ( qreal xpos , qreal ypos , qreal zpos )

构造向量采用坐标 ( xpos , ypos , zpos ).

QVector3D:: QVector3D (const QPoint & point )

Constructs a vector with x and y coordinates from a 2D point , and a z coordinate of 0.

QVector3D:: QVector3D (const QPointF & point )

Constructs a vector with x and y coordinates from a 2D point , and a z coordinate of 0.

QVector3D:: QVector3D (const QVector2D & vector )

构造 3D 向量从指定 2D vector 。z 坐标被设为 0。

另请参阅 toVector2D ().

QVector3D:: QVector3D (const QVector2D & vector , qreal zpos )

构造 3D 向量从指定 2D vector 。z 坐标被设为 zpos .

另请参阅 toVector2D ().

QVector3D:: QVector3D (const QVector4D & vector )

构造 3D 向量从指定 4D vector . The w coordinate is dropped.

另请参阅 toVector4D ().

[static] QVector3D QVector3D:: crossProduct (const QVector3D & v1 , const QVector3D & v2 )

Returns the cross-product of vectors v1 and v2 , which corresponds to the normal vector of a plane defined by v1 and v2 .

另请参阅 normal ().

qreal QVector3D:: distanceToLine (const QVector3D & point , const QVector3D & direction ) const

Returns the distance that this vertex is from a line defined by point and the unit vector direction .

若 direction is a null vector, then it does not define a line. In that case, the distance from point to this vertex is returned.

另请参阅 distanceToPlane ().

qreal QVector3D:: distanceToPlane (const QVector3D & plane , const QVector3D & normal ) const

Returns the distance from this vertex to a plane defined by the vertex plane 和 normal unit vector. The normal parameter is assumed to have been normalized to a unit vector.

The return value will be negative if the vertex is below the plane, or zero if it is on the plane.

另请参阅 normal () 和 distanceToLine ().

qreal QVector3D:: distanceToPlane (const QVector3D & plane1 , const QVector3D & plane2 , const QVector3D & plane3 ) const

这是重载函数。

Returns the distance from this vertex a plane defined by the vertices plane1 , plane2 and plane3 .

The return value will be negative if the vertex is below the plane, or zero if it is on the plane.

The two vectors that define the plane are plane2 - plane1 and plane3 - plane1 .

另请参阅 normal () 和 distanceToLine ().

[static] qreal QVector3D:: dotProduct (const QVector3D & v1 , const QVector3D & v2 )

返回点积为 v1 and v2 .

bool QVector3D:: isNull () const

Returns true if the x, y, and z coordinates are set to 0.0, otherwise returns false.

qreal QVector3D:: length () const

从原点返回向量长度。

另请参阅 lengthSquared () 和 normalized ().

qreal QVector3D:: lengthSquared () const

Returns the squared length of the vector from the origin. This is equivalent to the dot product of the vector with itself.

另请参阅 length () 和 dotProduct ().

[static] QVector3D QVector3D:: normal (const QVector3D & v1 , const QVector3D & v2 )

Returns the normal vector of a plane defined by vectors v1 and v2 , normalized to be a unit vector.

使用 crossProduct () to compute the cross-product of v1 and v2 if you do not need the result to be normalized to a unit vector.

另请参阅 crossProduct () 和 distanceToPlane ().

[static] QVector3D QVector3D:: normal (const QVector3D & v1 , const QVector3D & v2 , const QVector3D & v3 )

这是重载函数。

Returns the normal vector of a plane defined by vectors v2 - v1 and v3 - v1 , normalized to be a unit vector.

使用 crossProduct () to compute the cross-product of v2 - v1 and v3 - v1 if you do not need the result to be normalized to a unit vector.

另请参阅 crossProduct () 和 distanceToPlane ().

void QVector3D:: normalize ()

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.

另请参阅 length () 和 normalized ().

QVector3D QVector3D:: normalized () const

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.

另请参阅 length () 和 normalize ().

void QVector3D:: setX ( qreal x )

将此点的 X 坐标设为给定 x 坐标。

另请参阅 x (), setY ()，和 setZ ().

void QVector3D:: setY ( qreal y )

将此点的 Y 坐标设为给定 y 坐标。

另请参阅 y (), setX ()，和 setZ ().

void QVector3D:: setZ ( qreal z )

Sets the z coordinate of this point to the given z 坐标。

另请参阅 z (), setX ()，和 setY ().

QPoint QVector3D:: toPoint () const

返回 QPoint form of this 3D vector. The z coordinate is dropped.

另请参阅 toPointF () 和 toVector2D ().

QPointF QVector3D:: toPointF () const

返回 QPointF form of this 3D vector. The z coordinate is dropped.

另请参阅 toPoint () 和 toVector2D ().

QVector2D QVector3D:: toVector2D () const

Returns the 2D vector form of this 3D vector, dropping the z coordinate.

另请参阅 toVector4D () 和 toPoint ().

QVector4D QVector3D:: toVector4D () const

Returns the 4D form of this 3D vector, with the w coordinate set to zero.

另请参阅 toVector2D () 和 toPoint ().

qreal QVector3D:: x () const

返回此点的 X 坐标。

另请参阅 setX (), y ()，和 z ().

qreal QVector3D:: y () const

返回此点的 Y 坐标。

另请参阅 setY (), x ()，和 z ().

qreal QVector3D:: z () const

返回此点的 z 坐标。

另请参阅 setZ (), x ()，和 y ().

QVector3D:: operator QVariant () const

Returns the 3D vector as a QVariant .

QVector3D & QVector3D:: operator*= ( qreal factor )

Multiplies this vector's coordinates by the given factor , and returns a reference to this vector.

另请参阅 operator/= ().

QVector3D & QVector3D:: operator*= (const QVector3D & vector )

这是重载函数。

Multiplies the components of this vector by the corresponding components in vector .

Note: this is not the same as the crossProduct () of this vector and vector .

另请参阅 crossProduct ().

QVector3D & QVector3D:: operator+= (const QVector3D & vector )

添加给定 vector to this vector and returns a reference to this vector.

另请参阅 operator-= ().

QVector3D & QVector3D:: operator-= (const QVector3D & vector )

减去给定 vector from this vector and returns a reference to this vector.

另请参阅 operator+= ().

QVector3D & QVector3D:: operator/= ( qreal divisor )

Divides this vector's coordinates by the given divisor , and returns a reference to this vector.

另请参阅 operator*= ().

相关非成员

bool qFuzzyCompare (const QVector3D & v1 , const QVector3D & v2 )

返回 true 若 v1 and v2 are equal, allowing for a small fuzziness factor for floating-point comparisons; false otherwise.

bool operator!= (const QVector3D & v1 , const QVector3D & v2 )

返回 true 若 v1 不等于 v2 ; otherwise returns false. This operator uses an exact floating-point comparison.

const QVector3D operator* ( qreal factor , const QVector3D & vector )

返回副本为给定 vector ，乘以给定 factor .

另请参阅 QVector3D::operator*= ().

const QVector3D operator* (const QVector3D & vector , qreal factor )

返回副本为给定 vector ，乘以给定 factor .

另请参阅 QVector3D::operator*= ().

const QVector3D operator* (const QVector3D & v1 , const QVector3D & v2 )

Multiplies the components of v1 by the corresponding components in v2 .

Note: this is not the same as the crossProduct() of v1 and v2 .

另请参阅 QVector3D::crossProduct ().

const QVector3D operator+ (const QVector3D & v1 , const QVector3D & v2 )

返回 QVector3D object that is the sum of the given vectors, v1 and v2 ；分别相加各分量。

另请参阅 QVector3D::operator+= ().

const QVector3D operator- (const QVector3D & v1 , const QVector3D & v2 )

返回 QVector3D 对象的形成是通过减去 v2 from v1 ；分别减去各分量。

另请参阅 QVector3D::operator-= ().

const QVector3D operator- (const QVector3D & vector )

这是重载函数。

返回 QVector3D object that is formed by changing the sign of all three components of the given vector .

相当于 QVector3D(0,0,0) - vector .

const QVector3D operator/ (const QVector3D & vector , qreal divisor )

返回 QVector3D object formed by dividing all three components of the given vector 通过给定 divisor .

另请参阅 QVector3D::operator/= ().

QDataStream & operator<< ( QDataStream & stream , const QVector3D & vector )

写入给定 vector 到给定 stream 并返回流引用。

另请参阅 序列化 Qt 数据类型 .

bool operator== (const QVector3D & v1 , const QVector3D & v2 )

返回 true 若 v1 等于 v2 ; otherwise returns false. This operator uses an exact floating-point comparison.

QDataStream & operator>> ( QDataStream & stream , QVector3D & vector )

读取 3D 向量从给定 stream 进给定 vector 并返回流引用。

另请参阅 序列化 Qt 数据类型 .