Design And Implementation Of A Three-dimensional Widget Set

With the extensive application of embedded system, needs of GUI are more necessary for embedded products. OpenGL, as representative of three-dimensional graphics system, conveniently and flexibly achieves high-level two-dimensional and three-dimensional graphic technolgy, but its programming is not easy for developers to master. Therefore, it is very important to achieve a three-dimensional graphics system or control set which is of feature-rich, succinct code, the characteristics of highly reliable and efficient.Bsaed on the demands of online interactive high-definition player developed by routon electronic stock limited company, the overall design of three-dimensional widget set is given by analyzing three-dimensional graphics system Clutter. It briefly introduces the composition of widget about embedded three-dimensional widget set, class hierarchy and its event handling mechanism.It describes the general structure of three-dimensional widgets, and it analyzes and explains events of application registered. By the method of focus group and mechanism of event bubbling it solves the problem of switching the focus group. By the method of packaging container it solves the problem of switching focus groups. A three-dimensional widget of the style configuration file format is designed, which realizes to custom style of a widget's appearance.Designing and achieving a number of complex control with animation effects is based on the actual demands of online interactive high-definition player. Taking introdution widget and tile widget for exeample, it detailedly analyzes and introduces the achieving methods and steps of widgets.Introduction widget realizes to display all types of information about current film, and dynamicly increases and removes button according to the user's operation. For more information on type, complex functions and some information displayed with some special effects, the widget is achieved by blocking. By cloning, fliping and redrawing of the original video object it achieves the reflection effects; and by creating, destructing and real-time distributing for button it achieves dynamic adding and deleting of buttons; and by time limits and widget's opacity, it achieves a animation of focus image's breath.Tile widget is used for dynamic browsing of mass video information. The implementation of tile widget adoptes the method of local creating. In other words, it always creates and displays a part of video information, but it needs to records the basic information of other's video not displayed.