PORTABLE OPERATING ENVIRONMENT FOR INFORMATION DEVICES

摘要

A client software program for use on an embedded computing device includes an operating system layer including an abstraction layer, a programming environment, and an application framework including a package manager. The client is configured to interface with a client support server including a package repository, for receiving package data for running a software package on the embedded computing device. A graphics driver includes a shape function layer and a framebuffer access macro layer. When the first drawing surface is rendered as partially overlapping the second drawing surface, a visible portion of the second drawing surface is computed as a set of retangular clip segments. User interface component data and data used to factorize the way it is rendered are logically seperated.