Fl_Image
   |
   +----Fl_Bitmap
           |
           +----Fl_XBM_Image
#include <FL/Fl_Bitmap.H>
The Fl_Bitmap class supports caching and drawing of mono-color (bitmap) images. Images are drawn using the current color.
The constructors create a new bitmap from the specified bitmap data.
The destructor free all memory and server resources that are used by the bitmap.