DirectFB Overview (v0.1) Andreas Hundt
[email protected] ¡ September 11, 2001 Abstract This document discusses features and concepts of DirectFB. It is work in progress. Contents 1 Introduction 2 1.1 Goals . 2 1.2 Features . 2 1.2.1 Graphic Operations . 2 1.2.2 Windowing System . 3 1.2.3 Resource Management . 3 1.2.4 Graphic Drivers . 3 1.2.5 Input Drivers . 3 1.2.6 Image Loading . 4 1.2.7 Video Playback . 4 1.2.8 Font Rendering . 4 2 DirectFB architecture 5 2.1 Access to the graphics hardware by DirectFB . 5 2.2 Access to input devices by DirectFB . 5 2.3 Important terms used by DirectFB . 5 2.3.1 Blitting . 5 2.3.2 Surface . 6 2.3.3 SubSurface . 6 2.3.4 Layer . 6 2.3.5 Window / Windowstack . 7 2.4 Example of a Layer/Window configuration . 7 3 DirectFB API Concept 8 3.1 The DirectFB Super Interface . 8 3.2 Interface Diagram . 8 3.3 Loadable Modules . 8 3.4 Example code . 9 1 1 Introduction DirectFB is a thin library that provides hardware graphics acceleration, input device handling and abstraction, integrated windowing system with support for translucent windows and multiple display layers on top of the Linux Framebuffer Device. It is a complete hardware abstraction layer with software fallbacks for ev- ery graphics operation that is not supported by the underlying hardware. DirectFB was designed with embedded systems in mind. It offers maximum hardware accel- erated performance at a minimum of resource usage and overhead.