| Qwt User's Guide
    5.2.3
    | 
#include <qwt_color_map.h>

| Public Types | |
| enum | Format { RGB, Indexed } | 
| Public Member Functions | |
| QwtColorMap (Format=QwtColorMap::RGB) | |
| virtual | ~QwtColorMap () | 
| QColor | color (const QwtDoubleInterval &, double value) const | 
| virtual unsigned char | colorIndex (const QwtDoubleInterval &interval, double value) const =0 | 
| virtual QVector< QRgb > | colorTable (const QwtDoubleInterval &) const | 
| virtual QwtColorMap * | copy () const =0 | 
| Format | format () const | 
| virtual QRgb | rgb (const QwtDoubleInterval &interval, double value) const =0 | 
QwtColorMap is used to map values into colors.
For displaying 3D data on a 2D plane the 3rd dimension is often displayed using colors, like f.e in a spectrogram.
Each color map is optimized to return colors for only one of the following image formats:
| enum QwtColorMap::Format | 
| 
 | inline | 
Map a value into a color
| interval | Valid interval for values | 
| value | Value | 
| 
 | pure virtual | 
Map a value of a given interval into a color index
| interval | Range for the values | 
| value | Value | 
Implemented in QwtLinearColorMap.
| 
 | virtual | 
Build and return a color map of 256 colors
The color table is needed for rendering indexed images in combination with using colorIndex().
| interval | Range for the values | 
| 
 | inline | 
| 
 | pure virtual | 
Map a value of a given interval into a rgb value.
| interval | Range for the values | 
| value | Value | 
Implemented in QwtAlphaColorMap, and QwtLinearColorMap.
 1.8.1
 1.8.1