This directory contains the interface to implement platform-dependent
versions of a display, a visual, and a window.  Also available is file
I/O, text console output, time and timers, querying the user name,
environment variables, signal handling, and more.

BzfDisplay -- event handling, screen size, and video format changing
BzfVisual -- wraps pixel format selection
BzfWindow -- window management, gamma control, & mouse stuff
BzfJoystick -- joystick management