Материал из Wiki.crossplatform.ru

Внимание: Актуальная версия перевода документации находится здесь

__NOTOC__

[править] QPainterPathStroker Class Reference
^{[модуль QtGui ]}

The QPainterPathStroker class is used to generate fillable outlines for a given painter path. Далее...

 #include <QPainterPathStroker>

This class was introduced in Qt 4.1.

• Список всех членов, включая унаследованные

[править] Открытые функции

• QPainterPathStroker ()
• ~QPainterPathStroker ()
• Qt::PenCapStyle capStyle () const
• QPainterPath createStroke ( const QPainterPath & path ) const
• qreal curveThreshold () const
• qreal dashOffset () const
• QVector<qreal> dashPattern () const
• Qt::PenJoinStyle joinStyle () const
• qreal miterLimit () const
• void setCapStyle ( Qt::PenCapStyle style )
• void setCurveThreshold ( qreal threshold )
• void setDashOffset ( qreal offset )
• void setDashPattern ( Qt::PenStyle style )
• void setDashPattern ( const QVector<qreal> & dashPattern )
• void setJoinStyle ( Qt::PenJoinStyle style )
• void setMiterLimit ( qreal limit )
• void setWidth ( qreal width )
• qreal width () const

[править] Подробное описание

The QPainterPathStroker class is used to generate fillable outlines for a given painter path.

By calling the createStroke() function, passing a given QPainterPath as argument, a new painter path representing the outline of the given path is created. The newly created painter path can then be filled to draw the original painter path's outline.

You can control the various design aspects (width, cap styles, join styles and dash pattern) of the outlining using the following functions:

• setWidth()
• setCapStyle()
• setJoinStyle()
• setDashPattern()

The setDashPattern() function accepts both a Qt::PenStyle object and a vector representation of the pattern as argument.

In addition you can specify a curve's threshold, controlling the granularity with which a curve is drawn, using the setCurveThreshold() function. The default threshold is a well adjusted value (0.25), and normally you should not need to modify it. However, you can make the curve's appearance smoother by decreasing its value.

You can also control the miter limit for the generated outline using the setMiterLimit() function. The miter limit describes how far from each join the miter join can extend. The limit is specified in the units of width so the pixelwise miter limit will be miterlimit * width. This value is only used if the join style is Qt::MiterJoin.

The painter path generated by the createStroke() function should only be used for outlining the given painter path. Otherwise it may cause unexpected behavior. Generated outlines also require the Qt::WindingFill rule which is set by default.

See also QPen and QBrush.

[править] Описание функций-членов

[править]

QPainterPathStroker::QPainterPathStroker ()

Creates a new stroker.

[править]

QPainterPathStroker::~QPainterPathStroker ()

Destroys the stroker.

[править]

Qt::PenCapStyle QPainterPathStroker::capStyle () const

Returns the cap style of the generated outlines.

See also setCapStyle().

[править]

QPainterPath QPainterPathStroker::createStroke ( const QPainterPath & path ) const

Generates a new path that is a fillable area representing the outline of the given path.

The various design aspects of the outline are based on the stroker's properties: width(), capStyle(), joinStyle(), dashPattern(), curveThreshold() and miterLimit().

The generated path should only be used for outlining the given painter path. Otherwise it may cause unexpected behavior. Generated outlines also require the Qt::WindingFill rule which is set by default.

[править]

qreal QPainterPathStroker::curveThreshold () const

Returns the curve flattening threshold for the generated outlines.

See also setCurveThreshold().

[править]

qreal QPainterPathStroker::dashOffset () const

Returns the dash offset for the generated outlines.

Смотрите также setDashOffset().

[править]

QVector< qreal> QPainterPathStroker::dashPattern () const

Returns the dash pattern for the generated outlines.

See also setDashPattern().

[править]

Qt::PenJoinStyle QPainterPathStroker::joinStyle () const

Returns the join style of the generated outlines.

See also setJoinStyle().

[править]

qreal QPainterPathStroker::miterLimit () const

Returns the miter limit for the generated outlines.

See also setMiterLimit().

[править]

void QPainterPathStroker::setCapStyle ( Qt::PenCapStyle style )

Sets the cap style of the generated outlines to style. If a dash pattern is set, each segment of the pattern is subject to the cap style.

See also capStyle().

[править]

void QPainterPathStroker::setCurveThreshold ( qreal threshold )

Specifies the curve flattening threshold, controlling the granularity with which the generated outlines' curve is drawn.

The default threshold is a well adjusted value (0.25), and normally you should not need to modify it. However, you can make the curve's appearance smoother by decreasing its value.

See also curveThreshold().

[править]

void QPainterPathStroker::setDashOffset ( qreal offset )

Sets the dash offset for the generated outlines to offset.

Смотрите также dashOffset().

[править]

void QPainterPathStroker::setDashPattern ( Qt::PenStyle style )

Sets the dash pattern for the generated outlines to style.

See also dashPattern().

[править]

void QPainterPathStroker::setDashPattern ( const QVector< qreal> & dashPattern )

Эта перегруженная функция предоставлена для удобства.

Sets the dash pattern for the generated outlines to dashPattern. This function makes it possible to specify custom dash patterns.

Each element in the vector contains the lengths of the dashes and spaces in the stroke, beginning with the first dash in the first element, the first space in the second element, and alternating between dashes and spaces for each following pair of elements.

The vector can contain an odd number of elements, in which case the last element will be extended by the length of the first element when the pattern repeats.

[править]

void QPainterPathStroker::setJoinStyle ( Qt::PenJoinStyle style )

Sets the join style of the generated outlines to style.

See also joinStyle().

[править]

void QPainterPathStroker::setMiterLimit ( qreal limit )

Sets the miter limit of the generated outlines to limit.

The miter limit describes how far from each join the miter join can extend. The limit is specified in units of the currently set width. So the pixelwise miter limit will be miterlimit * width.

This value is only used if the join style is Qt::MiterJoin.

See also miterLimit().

[править]

void QPainterPathStroker::setWidth ( qreal width )

Sets the width of the generated outline painter path to width.

The generated outlines will extend approximately 50% of width to each side of the given input path's original outline.

See also width().

[править]

qreal QPainterPathStroker::width () const

Returns the width of the generated outlines.

See also setWidth().