Qwt User's Guide: QwtAlphaColorMap Class Reference

Qwt User's Guide 6.2.0

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:

## Public Member Functions
| QwtAlphaColorMap (const QColor &=QColor(Qt::gray))
| Constructor. More...
virtual | ~QwtAlphaColorMap ()
| Destructor.
void | setAlphaInterval (int alpha1, int alpha2)
int | alpha1 () const
int | alpha2 () const
void | setColor (const QColor &)
QColor | color () const
virtual QRgb | rgb (const QwtInterval &, double value) const override
| Map a value of a given interval into a alpha value. More...
Public Member Functions inherited from QwtColorMap
| QwtColorMap (Format=QwtColorMap::RGB)
virtual | ~QwtColorMap ()
| Destructor.
void | setFormat (Format)
virtual uint | colorIndex (int numColors, const QwtInterval &interval, double value) const
| Map a value of a given interval into a color index. More...
QColor | color (const QwtInterval &, double value) const
virtual QVector< QRgb > | colorTable (int numColors) const
virtual QVector< QRgb > | colorTable256 () const

## Additional Inherited Members
Public Types inherited from QwtColorMap
enum | Format { RGB , Indexed }
Public Attributes inherited from QwtColorMap
Format | const

## Detailed Description

QwtAlphaColorMap varies the alpha value of a color.

Definition at line 147 of file qwt_color_map.h.

## Constructor & Destructor Documentation

## ◆ QwtAlphaColorMap()

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

Constructor.

The alpha interval is initialized by 0 to 255.

Parameters

  color | Color of the map

See also
  setColor(), setAlphaInterval()

Definition at line 539 of file qwt_color_map.cpp.

## Member Function Documentation

## ◆ alpha1()

int QwtAlphaColorMap::alpha1 | ( |  | ) | const

Returns
  First alpha coordinate

See also
  setAlphaInterval()

Definition at line 600 of file qwt_color_map.cpp.

## ◆ alpha2()

int QwtAlphaColorMap::alpha2 | ( |  | ) | const

Returns
  Second alpha coordinate

See also
  setAlphaInterval()

Definition at line 609 of file qwt_color_map.cpp.

## ◆ color()

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

Returns
  the color

See also
  setColor()

Definition at line 571 of file qwt_color_map.cpp.

## ◆ rgb()

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

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

Parameters

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

Returns
  RGB value, with an alpha value

Implements QwtColorMap.

Definition at line 622 of file qwt_color_map.cpp.

## ◆ setAlphaInterval()

void QwtAlphaColorMap::setAlphaInterval | ( | int | alpha1,
|  | int | alpha2
| ) |  |

Set the interval for the alpha coordinate

alpha1/alpha2 need to be in the range 0 to 255, where 255 means opaque and 0 means transparent.

Parameters

  alpha1 | First alpha coordinate
  alpha2 | Second alpha coordinate

See also
  alpha1(), alpha2()

Definition at line 587 of file qwt_color_map.cpp.

## ◆ setColor()

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

Set the color

Parameters

  color | Color

See also
  color()

Definition at line 558 of file qwt_color_map.cpp.