internal void AssignLevelsToVertices()
{
foreach (Vertex v in vertices.Values)
{
v.level = Int32.MaxValue;
if (v != topVertex &&
v != bottomVertex &&
v.incomingEdges.Count == 0 &&
v.outgoingEdges.Count != 0)
{
topVertex.FindOrCreateOutgoingEdge(v);
}
}
topVertex.AssignLevel(0);
int maxLevel = 0;
foreach (Vertex v in vertices.Values)
{
if (v.level != Int32.MaxValue && maxLevel < v.level)
{
maxLevel = v.level;
}
}
bottomVertex.level = maxLevel + 1;
if (!this.isCallGraph)
{
// line up all the class names in one level
foreach (Edge e in bottomVertex.incomingEdges.Values)
{
e.FromVertex.level = maxLevel;
}
// this pass optimizes the layout somewhat
// so we have fewer back edges
// the idea is to move vertices to the left, if doing so creates no
// new back edges, but possibly removes some
bool change;
do
{
change = false;
foreach (Vertex v in vertices.Values)
{
int minOutgoingLevel = Int32.MaxValue;
foreach (Edge e in v.outgoingEdges.Values)
{
if (minOutgoingLevel > e.ToVertex.level)
{
minOutgoingLevel = e.ToVertex.level;
}
}
if (minOutgoingLevel < Int32.MaxValue && minOutgoingLevel - 1 > v.level)
{
v.level = minOutgoingLevel - 1;
change = true;
}
}
}while (change);
}
}
internal Edge FindOrCreateEdge(Vertex fromVertex, Vertex toVertex)
{
Debug.Assert(fromVertex != TopVertex || toVertex != BottomVertex);
return(fromVertex.FindOrCreateOutgoingEdge(toVertex));
}
internal Edge FindOrCreateEdge(Vertex fromVertex, Vertex toVertex)
{
Debug.Assert(fromVertex != topVertex || toVertex != bottomVertex);
return fromVertex.FindOrCreateOutgoingEdge(toVertex);
}
