Qwt User's Guide 6.1.5

Public Member Functions | List of all members
QwtAlphaColorMap Class Reference

QwtAlphaColorMap varies the alpha value of a color. More...

`#include <qwt_color_map.h>`

Inheritance diagram for QwtAlphaColorMap:
[legend]

## Public Member Functions

| QwtAlphaColorMap (const QColor &=QColor(Qt::gray))
virtual | ~QwtAlphaColorMap ()
| Destructor.
void | setColor (const QColor &)
QColor | color () const
virtual QRgb | rgb (const QwtInterval &, double value) const
| Map a value of a given interval into a alpha value. More...
Public Member Functions inherited from QwtColorMap
| QwtColorMap (Format=QwtColorMap::RGB)
| Constructor.
virtual | ~QwtColorMap ()
| Destructor.
Format | format () const
QColor | color (const QwtInterval &, double value) const
virtual QVector< QRgb > | colorTable (const QwtInterval &) const

## Additional Inherited Members

Public Types inherited from QwtColorMap
enum | Format { RGB, Indexed }

## Detailed Description

QwtAlphaColorMap varies the alpha value of a color.

## Constructor & Destructor Documentation

## ◆ QwtAlphaColorMap()

QwtAlphaColorMap::QwtAlphaColorMap | ( | const QColor & | color = `QColor( Qt::gray )` | ) |

Constructor

Parameters

  color | Color of the map

## Member Function Documentation

## ◆ color()

QColor QwtAlphaColorMap::color | ( |  | ) | const

Returns
  the color

See also
  setColor()

## ◆ rgb()

QRgb QwtAlphaColorMap::rgb | ( | const QwtInterval & | interval,
|  | double | value
| ) |  | const

virtual

Map a value of a given interval into a alpha value.

alpha := (value - interval.minValue()) / interval.width();

Parameters

  interval | Range for all values
  value | Value to map into a RGB value

Returns
  RGB value, with an alpha value

Implements QwtColorMap.

## ◆ setColor()

void QwtAlphaColorMap::setColor | ( | const QColor & | color | ) |

Set the color

Parameters

  color | Color

See also
  color()