If you decide to add a graphical user interface (GUI) to your appliance, you will be faced with the following challenge. On one hand, your appliance's graphics hardware is controlled by low-level commands that manipulate video memory. On the other hand, your users don't want to manipulate video memory; they want to manipulate high-level objects like menus and buttons. In order to build the kind of interface your users want, you will use a set of software layers known collectively as the graphics stack.

The graphics stack, as used for the Laddie appliance, is illustrated in Figure 11-1. The Linux framebuffer device driver provides a low-level but uniform interface to the graphics hardware's video memory. ...

Get Linux Appliance Design now with the O’Reilly learning platform.

O’Reilly members experience live online training, plus books, videos, and digital content from nearly 200 publishers.