GoLayoutLayeredDigraph Class

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GoLayoutLayeredDigraph provides an auto-layout for layered drawings of directed graphs.

Syntax

[DesignerCategory("Component")]
[Serializable()]
public class GoLayoutLayeredDigraph : GoLayout

Remarks

The method uses a hierarchical approach for creating drawings of digraphs with nodes arranged in layers. The layout algorithm consists of four-major steps: Cycle Removal, Layer Assignment, Crossing Reduction, and Straightening and Packing.

Example

Typical usage: To lay out only a portion of a document, you will need to construct a GoLayoutLayeredDigraphNetwork, initialize it with just the nodes and links that you want to use, and set the Network property. Read the GoLayout User Guide for more details.

GoDocument doc = goView1.Document;
doc.StartTransaction();
GoLayoutLayeredDigraph layout = new GoLayoutLayeredDigraph();
layout.Document = doc;
layout.DirectionOption = GoLayoutDirection.Down;
layout.ColumnSpacing = 15;
layout.LayerSpacing = 10;
// ...maybe set other properties...
layout.PerformLayout();
doc.FinishTransaction("layout");

GoDocument doc = goView1.Document;
doc.StartTransaction();
GoLayoutLayeredDigraph layout = new GoLayoutLayeredDigraph();
layout.Document = doc;
layout.Network = layout.CreateNetwork();
// if you want to start off with the network representing the complete document,
// and then remove the nodes (or links) that you don't want:
layout.Network.AddNodesAndLinksFromCollection(doc, true);
foreach (GoObject obj in doc) {
  if (...obj is a node that you want to exclude from the layout...) {
    layout.Network.DeleteNode(obj);  // there is also a DeleteLink method
  }
}
layout.DirectionOption = GoLayoutDirection.Down;
layout.ColumnSpacing = 15;
layout.LayerSpacing = 10;
// ...maybe set other properties...
layout.PerformLayout();
doc.FinishTransaction("layout");

Reference

GoLayoutLayeredDigraph Members
Northwoods.Go.Layout Namespace

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