Display objects

Figure 5.2 illustrates the structure and relationship of the many objects which are used by VMD for storing and rendering graphical objects. These objects are described in detail in section 6.3. Images are displayed through the use of four main objects (and subclasses thereof):

1. DisplayDevice objects, which are responsible for rendering a list of drawing commands to a given device or file;
2. DispCmd objects, of which there are several subclasses; each DispCmd subclass represents a single drawing command, such as a command to draw a line or to set the current color.
3. Displayable objects, which each represent a single graphical item with a list of drawing commands that may be rendered to a DisplayDevice;
4. Scene objects, which store lists of Displayable objects. When requested, a Scene takes a given DisplayDevice and requests the device to render each of the Displayable objects it stores.

 

 
• Device-Specific Rendering.
• Drawing Tokens.
• objects.
• The .
• Colors.
• Picking Items.