QwtVectorFieldSymbol类 参考

Defines abstract interface for arrow drawing routines. 更多...

#include <qwt_vectorfield_symbol.h>

类 QwtVectorFieldSymbol 继承关系图:

Public 成员函数
	QwtVectorFieldSymbol ()
	Constructor
virtual	~QwtVectorFieldSymbol ()
	Destructor
virtual void	setLength (qreal length)=0
	Set the length of the symbol/arrow
virtual qreal	length () const =0
	Return the length of the symbol/arrow
virtual void	paint (QPainter *) const =0
	Draw the symbol/arrow

详细描述

Defines abstract interface for arrow drawing routines.

Arrow needs to be drawn horizontally with arrow tip at coordinate 0,0. arrowLength() shall return the entire length of the arrow (needed to translate the arrow for tail/centered alignment). setArrowLength() defines arror length in pixels (screen coordinates). It can be implemented to adjust other geometric properties such as the head size and width of the arrow. It is always called before paint().

A new arrow implementation can be set with QwtPlotVectorField::setArrowSymbol(), whereby ownership is transferred to the plot field.

成员函数说明

length()

virtual qreal QwtVectorFieldSymbol::length ( ) const

pure virtual

Return the length of the symbol/arrow

在 QwtVectorFieldArrow , 以及 QwtVectorFieldThinArrow 内被实现.

paint()

virtual void QwtVectorFieldSymbol::paint ( QPainter *  ) const

pure virtual

Draw the symbol/arrow

在 QwtVectorFieldArrow , 以及 QwtVectorFieldThinArrow 内被实现.

setLength()

virtual void QwtVectorFieldSymbol::setLength ( qreal  length )

pure virtual

Set the length of the symbol/arrow

在 QwtVectorFieldArrow , 以及 QwtVectorFieldThinArrow 内被实现.

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该类的文档由以下文件生成:

• /home/runner/work/QWT/QWT/src/plot/qwt_vectorfield_symbol.h
• /home/runner/work/QWT/QWT/src/plot/qwt_vectorfield_symbol.cpp