The RL algorithm

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The Random Layout (RL) algorithm is not really a layout algorithm. It simply places the nodes at randomly computed positions inside a user-defined region. Nevertheless, the Random Layout algorithm can be useful when a random, initial placement is needed by another layout algorithm or in cases where an aesthetic, readable drawing is not important.

Example of RL

In CSS

The following sample CSS specification uses the Random Layout algorithm. The CSS specification can be loaded as style file into an application that uses the IlvDiagrammer class (see Graph layout in Rogue Wave JViews Diagrammer).

SDM {
    GraphLayout : "true";
    LinkLayout  : "false";
}

GraphLayout {
    linkStyle            : "STRAIGHT_LINE_STYLE";
}

In Java™

The following code sample uses the IlvRandomLayout class. This code sample shows how to perform a Random Layout on a grapher directly without using a diagram component or any style sheet:

 ...
import ilog.views.*;
import ilog.views.graphlayout.*;
import ilog.views.graphlayout.random.*;
 ...
IlvGrapher grapher = new IlvGrapher();
IlvManagerView view = new IlvManagerView(grapher);
 
 ... /*  Fill in here the grapher with nodes and links in */
 
IlvRandomLayout layout = new IlvRandomLayout();
layout.attach(grapher);
try {
        IlvGraphLayoutReport layoutReport = layout.performLayout();

        int code = layoutReport.getCode();

        System.out.println("Layout completed (" +
          layoutReport.codeToString(code) + ")");
}
catch (IlvGraphLayoutException e) {
        System.err.println(e.getMessage());
}

Current section

Random layout (RL)