The root lays the foundation for the contents by providing various graphical layers , such as connection layers , handle layers , etc . , and possibly zoom or other functionality at the viewer level 根通过提供各种图形层(例如连接层和句柄层等)以及可能会在查看器级别提供的视图缩放或其它功能,为内容打下基础。
Firstly , we analysed the osd graphics device driver , puting forward the design of graphical display memory and memory buffer . this is the foundation for the development of the graphics engine 首先从分析osd图形层的设备驱动入手,提出了图形显示内存和图形内存缓冲区的设计方案,为图形引擎的实现奠定了基础。