| Qwt User's Guide
    6.2.0
    | 
QwtColorMap is used to map values into colors. More...
#include <qwt_color_map.h>
| Public Types | |
| enum | Format { RGB , Indexed } | 
| Public Member Functions | |
| QwtColorMap (Format=QwtColorMap::RGB) | |
| virtual | ~QwtColorMap () | 
| Destructor. | |
| void | setFormat (Format) | 
| virtual QRgb | rgb (const QwtInterval &interval, double value) const =0 | 
| 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 | 
| Public Attributes | |
| Format | const | 
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:
Definition at line 37 of file qwt_color_map.h.
| enum QwtColorMap::Format | 
Format for color mapping
| Enumerator | |
|---|---|
| RGB | The map is intended to map into RGB values. | 
| Indexed | Map values into 8 bit values, that are used as indexes into the color table. Indexed color maps are used to generate QImage::Format_Indexed8 images. The calculation of the color index is usually faster and the resulting image has a lower memory footprint. 
 | 
Definition at line 45 of file qwt_color_map.h.
| 
 | explicit | 
Constructor
| format | Format of the color map | 
Definition at line 249 of file qwt_color_map.cpp.
| 
 | inline | 
Map a value into a color
| interval | Valid interval for values | 
| value | Value | 
Definition at line 248 of file qwt_color_map.h.
| 
 | virtual | 
Map a value of a given interval into a color index.
| numColors | Number of colors | 
| interval | Range for all values | 
| value | Value to map into a color index | 
Reimplemented in QwtLinearColorMap.
Definition at line 278 of file qwt_color_map.cpp.
| 
 | virtual | 
Build and return a color map of arbitrary number of colors
The color table is needed for rendering indexed images in combination with using colorIndex().
| numColors | Number of colors | 
Definition at line 325 of file qwt_color_map.cpp.
| 
 | virtual | 
Build and return a color map of 256 colors
The color table is needed for rendering indexed images in combination with using colorIndex().
Definition at line 304 of file qwt_color_map.cpp.
| 
 | pure virtual | 
Map a value of a given interval into a RGB value.
| interval | Range for the values | 
| value | Value | 
Implemented in QwtSaturationValueColorMap, QwtHueColorMap, QwtAlphaColorMap, and QwtLinearColorMap.
| void QwtColorMap::setFormat | ( | Format | format | ) | 
Set the format of the color map
| format | Format of the color map | 
Definition at line 264 of file qwt_color_map.cpp.
| 
 | inline | 
Definition at line 67 of file qwt_color_map.h.