QwtCompassWindArrow Class Reference

An indicator for the wind direction. More...

#include <qwt_dial_needle.h>

Inheritance diagram for QwtCompassWindArrow:

Collaboration diagram for QwtCompassWindArrow:

List of all members.

Public Types
enum	Style { Style1, Style2 }
	Style of the arrow. More...
Public Member Functions
	QwtCompassWindArrow (Style, const QColor &light=Qt::white, const QColor &dark=Qt::gray)
virtual void	draw (QPainter *, const QPoint &, int length, double direction, QPalette::ColorGroup=QPalette::Active) const
Static Public Member Functions
static void	drawStyle1Needle (QPainter *, const QPalette &, QPalette::ColorGroup, const QPoint &, int length, double direction)
static void	drawStyle2Needle (QPainter *, const QPalette &, QPalette::ColorGroup, const QPoint &, int length, double direction)

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Detailed Description

An indicator for the wind direction.

QwtCompassWindArrow shows the direction where the wind comes from.

• QColorGroup::Light
  Used for Style1, or the light half of Style2
• QColorGroup::Dark
  Used for the dark half of Style2

See also:

QwtDial, QwtCompass

Definition at line 170 of file qwt_dial_needle.h.

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Member Enumeration Documentation

enum QwtCompassWindArrow::Style

Style of the arrow.

Enumerator:

Style1
Style2

Definition at line 174 of file qwt_dial_needle.h.

    {
        Style1,
        Style2
    };

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Constructor & Destructor Documentation

QwtCompassWindArrow::QwtCompassWindArrow	(	Style	style,
		const QColor &	light = Qt::white,
		const QColor &	dark = Qt::gray
	)

Constructor

Parameters:

style	Arrow style
light	Light color
dark	Dark color

Definition at line 495 of file qwt_dial_needle.cpp.

References QwtDialNeedle::palette(), and QwtDialNeedle::setPalette().

                                                :
    d_style(style)
{
    QPalette palette;
    for ( int i = 0; i < QPalette::NColorGroups; i++ )
    {
        palette.setColor((QPalette::ColorGroup)i,
            QwtPalette::Light, light);
        palette.setColor((QPalette::ColorGroup)i,
            QwtPalette::Dark, dark);
    }

    setPalette(palette);
}

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Member Function Documentation

void QwtCompassWindArrow::draw	(	QPainter *	painter,
		const QPoint &	center,
		int	length,
		double	direction,
		QPalette::ColorGroup	colorGroup = QPalette::Active
	)		const [virtual]

Draw the needle

Parameters:

painter	Painter
center	Center of the dial, start position for the needle
length	Length of the needle
direction	Direction of the needle, in degrees counter clockwise
colorGroup	Color group, used for painting

Implements QwtDialNeedle.

Definition at line 520 of file qwt_dial_needle.cpp.

References drawStyle1Needle(), drawStyle2Needle(), QwtDialNeedle::palette(), and Style1.

{
    if ( d_style == Style1 )
    {
        drawStyle1Needle(painter, palette(), colorGroup,
            center, length, direction);
    }
    else
    {
        drawStyle2Needle(painter, palette(), colorGroup,
            center, length, direction); 
    }
}

void QwtCompassWindArrow::drawStyle1Needle	(	QPainter *	painter,
		const QPalette &	palette,
		QPalette::ColorGroup	colorGroup,
		const QPoint &	center,
		int	length,
		double	direction
	)		[static]

Draw a compass needle

Parameters:

painter	Painter
palette	Palette
colorGroup	colorGroup
center	Center of the dial, start position for the needle
length	Length of the needle
direction	Direction of the needle, in degrees counter clockwise

Definition at line 545 of file qwt_dial_needle.cpp.

References qwtDegree2Pos().

Referenced by draw().

{
    const QBrush lightBrush = palette.brush(colorGroup, QwtPalette::Light);

    const double AR1[] = {0, 0.4, 0.3, 1, 0.8, 1, 0.3, 0.4};
    const double AW1[] = {0, -45, -20, -15, 0, 15, 20, 45};

    const QPoint arrowCenter(center.x() + 1, center.y() + 1);

    QwtPolygon pa(8);
    pa.setPoint(0, arrowCenter);
    for (int i=1; i<8; i++) 
    {
        const QPoint p = qwtDegree2Pos(center, 
            AR1[i] * length, direction + AW1[i]);
        pa.setPoint(i, p);
    }

    painter->save();
    painter->setPen(Qt::NoPen);
    painter->setBrush(lightBrush);
    painter->drawPolygon(pa);
    painter->restore();
}

void QwtCompassWindArrow::drawStyle2Needle	(	QPainter *	painter,
		const QPalette &	palette,
		QPalette::ColorGroup	colorGroup,
		const QPoint &	center,
		int	length,
		double	direction
	)		[static]

Draw a compass needle

Parameters:

painter	Painter
palette	Palette
colorGroup	colorGroup
center	Center of the dial, start position for the needle
length	Length of the needle
direction	Direction of the needle, in degrees counter clockwise

Definition at line 582 of file qwt_dial_needle.cpp.

References qwtDegree2Pos().

Referenced by draw().

{
    const QBrush lightBrush = palette.brush(colorGroup, QwtPalette::Light);
    const QBrush darkBrush = palette.brush(colorGroup, QwtPalette::Dark);

    painter->save();
    painter->setPen(Qt::NoPen);

    const double angle = 12.0;
    const double ratio = 0.7;

    const QPoint arrowCenter(center.x() + 1, center.y() + 1);

    QwtPolygon pa(3);

    pa.setPoint(0, center);
    pa.setPoint(2, qwtDegree2Pos(arrowCenter, ratio * length, direction));

    pa.setPoint(1, qwtDegree2Pos(arrowCenter, length, direction + angle));
    painter->setBrush(darkBrush);
    painter->drawPolygon(pa);

    pa.setPoint(1, qwtDegree2Pos(arrowCenter, length, direction - angle));
    painter->setBrush(lightBrush);
    painter->drawPolygon(pa);

    painter->restore();
}

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The documentation for this class was generated from the following files:

• qwt_dial_needle.h
• qwt_dial_needle.cpp