public SimpleTreeLayoutAlgorithm(TGraph visitedGraph, IDictionary <TVertex, Point> vertexPositions, IDictionary <TVertex, Size> vertexSizes, SimpleTreeLayoutParameters parameters)
            : base(visitedGraph, vertexPositions, parameters)
        {
            //Contract.Requires( vertexSizes != null );
            //Contract.Requires( visitedGraph.Vertices.All( v => vertexSizes.ContainsKey( v ) ) );

            _sizes = new Dictionary <TVertex, Size>(vertexSizes);
        }
 public SimpleTreeLayoutAlgorithm(TGraph visitedGraph, IDictionary <TVertex, Point> vertexPositions, IDictionary <TVertex, Size> vertexSizes, SimpleTreeLayoutParameters parameters)
     : base(visitedGraph, vertexPositions, parameters)
 {
     VertexSizes = new Dictionary <TVertex, Size>(vertexSizes);
 }