NAME

XBlackPixel, XBlackPixelOfScreen, BlackPixel, BlackPixelOfScreen − get the black pixel value. 

Synopsis

unsigned long XBlackPixelOfScreen(screen)

      Screen *screen;

unsigned long XBlackPixel(display, screen_number)

      Display *display;
      int screen_number;

Arguments

screenSpecifies the appropriate Screen structure. 

displaySpecifies a connection to an X server; returned from XOpenDisplay(). 

screen_number
Specifies the appropriate screen number.

Description

Each screen has a default colormap which has pixel values for black and white already allocated.  These functions return the black pixel value.  Note that this pixel value only represents black in a screen’s default colormap.  XBlackPixel() and XBlackPixelOfScreen() are equivalent except that they require different arguments.  One requires a pointer to a Screen structure, while the other requires a screen number.  Unless you already have the pointer to a Screen structure in a variable, XBlackPixel*() is more convenient.  The C language macros BlackPixel() and BlackPixelOfScreen() are equivalent and slightly more efficient. 

See Also

XWhitePixel*(), XWhitePixelOfScreen(), XDefaultColormap*(). 

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