Linux Framebuffer Article Index for
Linux
Website Links For
Linux
 

Information About

Linux Framebuffer




The Linux Framebuffer (fbdev) is a graphic hardware-independent Abstraction Layer to show Graphics on a Console without relying on system-specific libraries such as SVGALib or the heavy Overhead of the X Window System .

It was originally implemented to allow the Linux Kernel to emulate a text console on systems such as the Apple Macintosh that do not have a text-mode display, and was later expanded to Linux's originally-supported IBM PC Compatible platform, where it became popular largely for the ability to show the Tux logo on boot up. More significantly, it serves as a way of displaying Unicode characters on the Linux console. Under the non-framebuffer, VGA display of the PC, comprehensive Unicode support was impossible, for VGA console fonts were limited to 512 characters.

Nowadays several Linux programs such as MPlayer , and libraries such as SDL or GTK+ can use the framebuffer immediately, avoiding the overhead of an X Server . This is particularly popular in Embedded System s.

The Linux framebuffer has long suffered from its poor performance, but there is now a library DirectFB which provides a framework for hardware acceleration.

FBUI (FrameBuffer UI) provides in-kernel windowing system (GUI) for the framebuffer subsystem at very low cost: the entire subsystem is about 50 kilobytes in size. It permits multiple programs to share the framebuffer simultaneously; it permits overlapping moveable windows; each program may have multiple windows; and it allows windows on every virtual console. Included with FBUI is libfbui which provides abstractions for windows, events, etc., as well as quite a few sample programs such as load monitor, clock, calculator, scribble pad, image viewer, window managers, and a simple MPEG2 player. FBUI includes an optimized code for the VESA framebuffer driver.


EXTERNAL LINKS