The QColor class provides colors based on RGB. ... QColor  ( int r, int g, int b )  . ... A color is normally specified in terms of RGB (red,green and blue) components, but it is also possible to specify HSV (hue,saturation and value) or set a color name (the names are copied from from the X11 color database). ... Check an internal hash table to see if we allocated an equal RGB value earlier. ... Allocates the RGB color and returns the pixel value. ... Returns the current color allocation context. ...