The following section describes how to define a Bob (blitter object). Like
VSprites, a Bob is a software construct designed to make animation easier.
The main advantage of a Bob over a VSprite is that it allows more colors
and a width greater than 16 pixels to be defined.

To create a Bob, you need both a Bob structure and a VSprite structure.
The components common to all GELs -- height, collision-handling
information, position in the drawing area and pointers to the image
definition -- are part of the VSprite structure.  The added features --
such as drawing sequence, data about saving and restoring the background,
and other features not applicable to VSprites -- are further specified in
the Bob structure.

 The VSprite Structure and Bobs        Bob Priorities 
 VSprite Flags and Bobs                Adding a Bob 
 The Bob Structure                     Removing a Bob 
 Using Bob Flags                       Sorting and Displaying Bobs 
 Specifying the Size of a Bob          Changing Bobs 
 Specifying the Shape of a Bob         Complete Bob Example 
 Specifying the Colors of a Bob        Double-Buffering 
 Other Items Influencing Bob Colors