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IrregularPlot class

The IrregularPlot class draws immediate mode lines and may be used to map overlay plots into an irregular rectangular coordinate space.


Header file:		ncarg/hlu/IrregularPlot.h
Class name:		irregularPlotClass
Class pointer:		NhlirregularPlotClass
Fortran class function:	NHLFIRREGULARPLOTCLASS
Superclass:		Transform
Composite classes:	IrregularTransformation,PlotManager


Local resources

The IrregularPlot object has no local resources.

Composite resources

Transformation resources

Transformation class resources specify the extent and direction of the data coordinate system. As the superclass of IrregularTransformation, you can access all Transformation resources.

IrregularTransformation resources

You can access all resources specific to the IrregularTransformation subclass. These resources specify the type of transformation for each axis, the coordinate arrays if required, and other associated parameters.

PlotManager resources

Assuming tfPlotManagerOn is True when an IrregularPlot object is created, you can access all PlotManager resources. You can also access resources for any of the PlotManager's composite class members. However, the PlotManager object modifies the access and behavior of some of the resources belonging to these objects, as follows:

Superclass resources

You can access all resources defined by the superclasses of the IrregularPlot object class, including:


Unlike most Transform subclasses, IrregularPlot has no specialized plot elements and no NhlDraw method of its own. Its primary function is to act as a base plot over which other plot objects may be overlaid in order to transform their data space into an irregular coordinate space. Like other members of the Transform class, IrregularPlot can also function as a "canvas" for drawing graphics primitives, either in data space or in NDC space.

You can transform a plot object into an irregularly gridded coordinate space by overlaying it on an irregularplot. The irregularly gridded space may encompass the data space of any number of plot objects with partially or completely disjoint data coordinate extents. You define the irregular mapping, as well as the coordinate axis extents and directions, using the resources of the IrregularTransformation object belonging to the IrregularPlot. Note that IrregularPlot is the only class that allows unrestricted access to all the resources of its IrregularTransformation object.

Assuming tfPlotManagerOn is True when you create an IrregularPlot object, the IrregularPlot object has the same plot management capabilities as any other plot object. The IrregularPlot object does not intercept any resources belonging to its PlotManager or the PlotManager's composite class members. Therefore, you access these resources just as described for the PlotManager object itself.

Support functions

The IrregularPlot object does not define any support functions, but inherits all the support functions available to its superclasses.


1. The status of the immediate mode drawing functions (DataPolyline) is not yet resolved.

2. The resources of the IrregularTransformation used to set the irregular coordinate transformation need to be updated to use GenArrays.

See also