Marked Polyline Displayer

A marked polyline displayer has the following basic characteristics:

Class

IlvMarkedPolylineChartDisplayer

Category

Composite

Number of real data sets displayed

1

Can be used with all types of projections

Yes

Number of child displayers

2 (1 scatter displayer + 1 polyline displayer)

Items drawn

Markers and/or Polyline

The marked polyline displayer is composed of a scatter displayer (an instance of the IlvScatterChartDisplayer class) and a polyline displayer (an instance of the IlvPolylineChartDisplayer class). Each child displayer can be customized individually. You can specify the palette, the marker type, and the marker size directly for the scatter displayer. You can specify the palette directly for the polyline displayer. Use the following methods to access the child displayers:

The Charts Library also provides some methods at the level of the IlvMarkedPolylineChartDisplayer class that allow you to set properties defined for child displayers more quickly. The following table lists all the properties that can be set at the level of the IlvMarkedPolylineChartDisplayer class. (For details on all the properties that can be set on a scatter displayer, see Scatter Displayer. For details on all the properties that can be set on a polyline displayer, see Polyline Displayer.)

Property

Methods

Default Value

General Properties

Markers Displayed

isMarkerVisible

setMarkerVisible

IlvTrue

Polyline Displayed

isLineVisible

setLineVisible

IlvTrue

Scatter Displayer Properties

Palette

getMarkerPalette

setMarkerPalette

0

Palette Foreground

getMarkerForeground

setMarkerForeground

0

Palette Background

getMarkerBackground

setMarkerBackground

0

Polyline Displayer Properties

Palette

getLinePalette

setLinePalette

0

Palette Foreground

getLineForeground

setLineForeground

0

Palette Background

getLineBackground

setLineBackground

0

By default, a marked polyline displayer displays a data set with both markers and a polyline. However, you can specify that only markers are to be displayed by setting the property Polyline Displayed to IlvFalse. You can specify that only a polyline is to be displayed by setting the property Markers Displayed to IlvFalse.

Marked Polyline Displayers in a Cartesian Chart and in a Polar Chart illustrates the fact that a marked polyline displayer can be used with all types of projections. Data sets are represented by marked polyline displayers in a Cartesian chart (using a Cartesian projection) and in a polar chart (using a polar projection).

Marked Polyline Displayers in a Cartesian Chart and in a Polar Chart

We can use the marked polyline displayer displaying the red lines and gold markers as an example. To create this displayer, we can use the following code:

IlvMarkedPolylineChartDisplayer* displayer =

new IlvMarkedPolylineChartDisplayer();

displayer->setMarkerForeground(dpy->getColor("gold"));

displayer->setLineForeground(dpy->getColor("red"));