QConicalGradient 類

The QConicalGradient class is used in combination with QBrush 以指定錐形漸變筆刷。 更多...

頭: #include <QConicalGradient>
qmake: QT += gui
繼承: QGradient

公共函數

QConicalGradient ()
QConicalGradient (const QPointF & center , qreal angle )
QConicalGradient (qreal cx , qreal cy , qreal angle )
qreal angle () const
QPointF center () const
void setAngle (qreal angle )
void setCenter (const QPointF & center )
void setCenter (qreal x , qreal y )

詳細描述

The QConicalGradient class is used in combination with QBrush 以指定錐形漸變筆刷。

Conical gradients interpolate interpolate colors counter-clockwise around a center point.

The colors in a gradient is defined using stop points of the QGradientStop type, i.e. a position and a color. Use the QGradient::setColorAt () 或 QGradient::setStops () function to define the stop points. It is the gradient's complete set of stop points that describes how the gradient area should be filled. If no stop points have been specified, a gradient of black at 0 to white at 1 is used.

In addition to the functions inherited from QGradient QConicalGradient 類提供 angle () 和 center () functions returning the start angle and center of the gradient.

注意, setSpread () function has no effect for conical gradients. The reason is that the conical gradient is closed by definition, i.e. the conical gradient fills the entire circle from 0 - 360 degrees, while the boundary of a radial or a linear gradient can be specified through its radius or final stop points, respectively.

另請參閱 QLinearGradient , QRadialGradient ,和 The Gradients Example .

成員函數文檔編製

QConicalGradient:: QConicalGradient ()

Constructs a conical with center at (0, 0) starting the interpolation at angle 0.

另請參閱 QGradient::setColorAt (), setCenter (),和 setAngle ().

QConicalGradient:: QConicalGradient (const QPointF & center , qreal angle )

Constructs a conical gradient with the given center , starting the interpolation at the given angle angle must be specified in degrees between 0 and 360.

另請參閱 QGradient::setColorAt () 和 QGradient::setStops ().

QConicalGradient:: QConicalGradient ( qreal cx , qreal cy , qreal angle )

Constructs a conical gradient with the given center ( cx , cy ), starting the interpolation at the given angle . The angle must be specified in degrees between 0 and 360.

另請參閱 QGradient::setColorAt () 和 QGradient::setStops ().

qreal QConicalGradient:: angle () const

Returns the start angle of the conical gradient in logical coordinates.

另請參閱 setAngle () 和 stops ().

QPointF QConicalGradient:: center () const

Returns the center of the conical gradient in logical coordinates.

另請參閱 setCenter () 和 stops ().

void QConicalGradient:: setAngle ( qreal angle )

angle to be the start angle for this conical gradient in logical coordinates.

該函數在 Qt 4.2 引入。

另請參閱 angle ().

void QConicalGradient:: setCenter (const QPointF & center )

Sets the center of this conical gradient in logical coordinates to center .

另請參閱 center ().

void QConicalGradient:: setCenter ( qreal x , qreal y )

這是重載函數。

Sets the center of this conical gradient in logical coordinates to ( x , y ).

另請參閱 center ().