QNX Screen Composited Windowing API
The principal components of the Windowing API are closely associated with each other. The following subsections describe briefly these components, or objects, and their associated relationships.
QNX Screen Composited Windowing API major API component associations
- A context provides the setting for graphics operations within a windowing environment. Using context-specific API components, you can identify and gain access to the objects on which you want to draw — windows, groups, displays, pixmaps, to set or change their properties and attributes.
- Events include window creation, setting properties, keyboard events, touch events, and so on.
- In a windowing environment, a window represents the fundamental drawing surface. Windows can display different kinds of content for different purposes, and in multiple types: application windows, child windows, embedded windows, and so on.
- Groups let you apply sets of properties to all windows in the group. Organize and manage windows as groups in your applications.
- Displays are physical devices that present images to their viewers — monitors, touch-screen displays, and so on. Using the display-specific API components, you can gain access to display properties, modes, and vsynch operations.
- Pixmaps are similar to bitmaps except that they can have multiple bits per pixel (a measurement of the depth of the pixmap) that store intensity or colour component values. Bitmaps, by contrast, have a depth of one bit per pixel.
- Buffers, important objects in computer graphics environments, are areas of memory not yet displayed that let you move data around quickly without taking up CPU cycles.