public void Layouting()
{
// If we have a given dot file, we can also simply read it back in
RootGraph root = RootGraph.FromDotFile(TestContext.CurrentContext.TestDirectory + "/out.dot");
// Let's have graphviz compute a dot layout for us
root.ComputeLayout();
// We can export this to svg
root.ToSvgFile(TestContext.CurrentContext.TestDirectory + "/dot_out.svg");
// Or programatically read out the layout attributes
Node nodeA = root.GetNode("A");
PointF position = nodeA.Position();
Assert.AreEqual("{X=43, Y=192.1739}", position.ToString());
// Like a bounding box of an object
RectangleF nodeboundingbox = nodeA.BoundingBox();
Assert.AreEqual("{X=16,Y=171.3391,Width=54,Height=41.66957}", nodeboundingbox.ToString());
// Or splines between nodes
Node nodeB = root.GetNode("B");
Edge edge = root.GetEdge(nodeA, nodeB, "Some edge name");
PointF[] spline = edge.FirstSpline();
string splineString = string.Join(", ", spline.Select(p => p.ToString()));
string expectedSplineString = "{X=0, Y=0}, {X=43, Y=171.29}, {X=43, Y=163.45},"
+ " {X=43, Y=154.26}, {X=43, Y=145.63}";
Assert.AreEqual(expectedSplineString, splineString);
GraphvizLabel nodeLabel = nodeA.GetLabel();
Assert.AreEqual("{X=36.25977,Y=181.4415,Width=13.48047,Height=21.46484}",
nodeLabel.BoundingBox().ToString());
Assert.AreEqual("Times-Roman", nodeLabel.FontName().ToString());
SubGraph cluster = root.GetSubgraph("cluster_1");
RectangleF clusterbox = cluster.BoundingBox();
RectangleF rootgraphbox = root.BoundingBox();
Assert.AreEqual("{X=8,Y=8,Width=70,Height=135.34}", clusterbox.ToString());
Assert.AreEqual("{X=0,Y=0,Width=142,Height=213.01}", rootgraphbox.ToString());
// Once all layout information is obtained from the graph, the resources should be
// reclaimed. To do this, the application should call the cleanup routine associated
// with the layout algorithm used to draw the graph. This is done by a call to
// FreeLayout(). A given graph can be laid out multiple times. The application, however,
// must clean up the earlier layout's information with a call to FreeLayout before
// invoking a new layout function.
root.FreeLayout();
// We can use layout engines other than dot by explicitly passing the engine we want
root.ComputeLayout(LayoutEngines.Neato);
root.ToSvgFile(TestContext.CurrentContext.TestDirectory + "/neato_out.svg");
}
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());
}
