public void Clusters()
{
RootGraph root = RootGraph.CreateNew("Graph with clusters", GraphType.Directed);
Node nodeA = root.GetOrAddNode("A");
Node nodeB = root.GetOrAddNode("B");
Node nodeC = root.GetOrAddNode("C");
Node nodeD = root.GetOrAddNode("D");
// When a subgraph name is prefixed with cluster,
// the dot layout engine will render it as a box around the containing nodes.
SubGraph cluster1 = root.GetOrAddSubgraph("cluster_1");
cluster1.AddExisting(nodeB);
cluster1.AddExisting(nodeC);
SubGraph cluster2 = root.GetOrAddSubgraph("cluster_2");
cluster2.AddExisting(nodeD);
// COMPOUND EDGES
// Graphviz does not really support edges from and to clusters. However, by adding an
// invisible dummynode and setting the ltail or lhead attributes of an edge this
// behavior can be faked. Graphviz will then draw an edge to the dummy node but clip it
// at the border of the cluster. We provide convenience methods for this.
// To enable this feature, Graphviz requires us to set the "compound" attribute to "true".
Graph.IntroduceAttribute(root, "compound", "true"); // Allow lhead/ltail
// The boolean indicates whether the dummy node should take up any space. When you pass
// false and you have a lot of edges, the edges may start to overlap a lot.
_ = root.GetOrAddEdge(nodeA, cluster1, false, "edge to a cluster");
_ = root.GetOrAddEdge(cluster1, nodeD, false, "edge from a cluster");
_ = root.GetOrAddEdge(cluster1, cluster1, false, "edge between clusters");
root.ComputeLayout();
SubGraph cluster = root.GetSubgraph("cluster_1");
RectangleF clusterbox = cluster.BoundingBox();
RectangleF rootgraphbox = root.BoundingBox();
Utils.AssertPattern(@"{X=[\d.]+,Y=[\d.]+,Width=[\d.]+,Height=[\d.]+}", clusterbox.ToString());
Utils.AssertPattern(@"{X=[\d.]+,Y=[\d.]+,Width=[\d.]+,Height=[\d.]+}", rootgraphbox.ToString());
}
public void GraphConstruction()
{
// You can programmatically construct graphs as follows
RootGraph root = RootGraph.CreateNew("Some Unique Identifier", GraphType.Directed);
// The node names are unique identifiers within a graph in Graphviz
Node nodeA = root.GetOrAddNode("A");
Node nodeB = root.GetOrAddNode("B");
Node nodeC = root.GetOrAddNode("C");
Node nodeD = root.GetOrAddNode("D");
// The edge name is only unique between two nodes
Edge edgeAB = root.GetOrAddEdge(nodeA, nodeB, "Some edge name");
Edge edgeBC = root.GetOrAddEdge(nodeB, nodeC, "Some edge name");
Edge anotherEdgeBC = root.GetOrAddEdge(nodeB, nodeC, "Another edge name");
// When a subgraph name is prefixed with cluster,
// the dot layout engine will render it as a box around the containing nodes.
SubGraph cluster = root.GetOrAddSubgraph("cluster_1");
cluster.AddExisting(nodeB);
cluster.AddExisting(nodeC);
// We can attach attributes to nodes, edges and graphs to store information and instruct
// graphviz by specifying layout parameters. At the moment we only support string
// attributes. Cgraph assumes that all objects of a given kind (graphs/subgraphs, nodes,
// or edges) have the same attributes. The attributes first have to be introduced for a
// certain kind, before we can use it.
Node.IntroduceAttribute(root, "my attribute", "defaultvalue");
nodeA.SetAttribute("my attribute", "othervalue");
// To introduce and set an attribute at the same time, there are convenience wrappers
edgeAB.SafeSetAttribute("color", "red", "black");
edgeBC.SafeSetAttribute("arrowsize", "2.0", "1.0");
// We can simply export this graph to a text file in dot format
root.ToDotFile(TestContext.CurrentContext.TestDirectory + "/out.dot");
}