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View class

All graphical objects are created from subclasses of the View class. They include TextItem, Title, TickMark, Legend, LabelBar, XyPlot, ContourPlot, MapPlot, StreamlinePlot, and VectorPlot.

View class objects inherit the viewport resources of the View class. The viewport is a rectangular subspace of NDC space (0. to 1. in both dimensions) that serves as the principal boundary of all View objects. The default viewport is (.2,.8) in X and (.2,.8) in Y. The viewport can be set through resource values in a resource file.

All View objects must have an ancestor in the instance hierarchy that is a Workstation object. A view can be only be drawn on the workstation that is its ancestor.

Some view objects such as XyPlot, ContourPlot, StreamlinePlot, and VectorPlot acquire their data from a DataItem class.

Composite graphical objects are created using the PlotManager class. Any View class name that ends in "Plot" (ContourPlot, XyPlot, StreamlinePlot, VectorPlot, and MapPlot) uses the PlotManager class to manage how multiple graphical objects are overlayed on the plot.

Annotations are placed on a plot under the control of the AnnoManager class. Annotations can be added to any plot that uses a View class object ending in the word "Plot," such as XyPlot, ContourPlot, StreamlinePlot, VectorPlot, or MapPlot.

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