QwtColorMap(3)

💅 QwtColorMap(3) — mapping values into colors, no cap ✨

okay so this page is straight outta the Library Functions Manual, and it’s all about QwtColorMap, bestie. 💖

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🌸 NAME 🌸

QwtColorMap is used to map values into colors. periodt.

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✨ SYNOPSIS ✨

#include <qwt_color_map.h>

Inherited by QwtAlphaColorMap, QwtHueColorMap, QwtLinearColorMap, and QwtSaturationValueColorMap. the family tree ate 💅

🎀 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.
• QColor color (const QwtInterval &, double value) const
• virtual QVector< QRgb > colorTable (int numColors) const
• virtual QVector< QRgb > colorTable256 () const

🌈 Public Attributes

• Format const

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📚 Detailed Description

QwtColorMap is used to map values into colors. literally its whole main character job 💅

For displaying 3D data on a 2D plane the 3rd dimension is often displayed using colors, like f.e in a spectrogram. that’s the vibe 🎨

Each color map is optimized to return colors for only one of the following image formats:

• QImage::Format_Indexed8
• QImage::Format_ARGB32

See also: QwtPlotSpectrogram, QwtScaleWidget.

Definition at line 37 of file qwt_color_map.h.

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🧚 Member Enumeration Documentation

enum QwtColorMap::Format

Format for color mapping. iconic little enum tbh.

See also: rgb(), colorIndex(), colorTable().

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. slay, efficient queen 💖

See also: colorIndex(), colorTable().

Definition at line 45 of file qwt_color_map.h.

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🎀 Constructor & Destructor Documentation

QwtColorMap::QwtColorMap (Format format = QwtColorMap::RGB) [explicit]

Constructor. the birth of a color-mapping icon ✨

Parameters

• format — Format of the color map

Definition at line 249 of file qwt_color_map.cpp.

QwtColorMap::~QwtColorMap () [virtual]

Destructor. bye bestie 🫶

Definition at line 255 of file qwt_color_map.cpp.

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💜 Member Function Documentation

QColor QwtColorMap::color (const QwtInterval & interval, double value) const [inline]

Map a value into a color. cute and direct.

Parameters

• interval — Valid interval for values
• value — Value

Returns

Color corresponding to value.

Definition at line 248 of file qwt_color_map.h.

uint QwtColorMap::colorIndex (int numColors, const QwtInterval & interval, double value) const [virtual]

Map a value of a given interval into a color index. lowkey the index-maker 💅

Parameters

• numColors — Number of colors
• interval — Range for all values
• value — Value to map into a color index

Returns

Index, between 0 and numColors - 1, or -1 for an invalid value.

Reimplemented in QwtLinearColorMap.

Definition at line 278 of file qwt_color_map.cpp.

QVector< QRgb > QwtColorMap::colorTable (int numColors) const [virtual]

Build and return a color map of arbitrary number of colors. custom palette energy ✨

The color table is needed for rendering indexed images in combination with using colorIndex().

Parameters

• numColors — Number of colors

Returns

A color table.

Definition at line 325 of file qwt_color_map.cpp.

QVector< QRgb > QwtColorMap::colorTable256 () const [virtual]

Build and return a color map of 256 colors. 256 is such a moment 🔥

The color table is needed for rendering indexed images in combination with using colorIndex().

Returns

A color table, that can be used for a QImage.

Definition at line 304 of file qwt_color_map.cpp.

virtual QRgb QwtColorMap::rgb (const QwtInterval & interval, double value) const [pure virtual]

Map a value of a given interval into a RGB value. pure virtual, pure vibes 💖

Parameters

• interval — Range for the values
• value — Value

Returns

RGB value, corresponding to value.

Implemented in QwtAlphaColorMap, QwtHueColorMap, QwtLinearColorMap, and QwtSaturationValueColorMap.

void QwtColorMap::setFormat (Format format)

Set the format of the color map. switch it up, bestie 💅

Parameters

• format — Format of the color map

Definition at line 264 of file qwt_color_map.cpp.

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🍓 Member Data Documentation

QwtColorMap::Format QwtColorMap::const [inline]

Initial value:

{
    return m_format

Returns

Intended format of the color map.

See also: Format.

Definition at line 67 of file qwt_color_map.h.

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👑 Author

Generated automatically by Doxygen for Qwt User's Guide from the source code. no cap, the docs wrote themselves 😭

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💖 signed with the cutest footer energy: source/version = Qwt User's Guide, page = QwtColorMap(3) — and the original footer has no date printed on it, so that’s all the date tea we have 🫶