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• Detailed Description

Detailed Description

QGLColormap provides a platform independent way of specifying and installing indexed colormaps for aQGLWidget. QGLColormap is especially useful when using theOpenGL color-index mode.

Under X11 you must use an X server that supports either aPseudoColor orDirectColor visual class. If your X server currently only provides aGrayScale,TrueColor,StaticColor orStaticGray visual, you will not be able to allocate colorcells for writing. If this is the case, try setting your X server to 8 bit mode. It should then provide you with at least aPseudoColor visual. Note that you may experience colormap flashing if your X server is running in 8 bit mode.

The size() of the colormap is always set to 256 colors. Note that under Windows you can also install colormaps in child widgets.

This class usesimplicit sharing as a memory and speed optimization.

Example of use:

#include <QApplication>#include <QGLColormap>int main(int argc,char*argv[]){QApplication app(argc, argv);    MySuperGLWidget widget;// a QGLWidget in color-index modeQGLColormap colormap;// This will fill the colormap with colors ranging from// black to white.constint size=256;for (int i=0; i< size;++i)        colormap.setEntry(i,qRgb(i, i, i));    widget.setColormap(colormap);    widget.show();return app.exec();}