private void DrawSubdivision(Subdivision division)
{
// generate new random subdivision if desired
if (division == null)
{
PointD offset = new PointD(OutputBox.Width * 0.2, OutputBox.Height * 0.2);
SizeD scale = new SizeD(OutputBox.Width * 0.6, OutputBox.Height * 0.6);
int count = MersenneTwister.Default.Next(4, 12);
PointD[] points = new PointD[count];
for (int i = 0; i < points.Length; i++)
{
points[i] = new PointD(
offset.X + MersenneTwister.Default.NextDouble() * scale.Width,
offset.Y + MersenneTwister.Default.NextDouble() * scale.Height);
}
// outer bounds for Voronoi pseudo-vertices
double margin = 3 * FontSize;
RectD bounds = new RectD(margin, margin,
OutputBox.Width - 2 * margin, OutputBox.Height - 2 * margin);
var result = Voronoi.FindAll(points, bounds);
division = result.ToVoronoiSubdivision().Source;
}
_division = division;
_division.Validate();
_nearestEdge = -1;
_edges = DrawSubdivision(OutputBox, FontSize, division);
OutputBox.Children.Add(VertexCircle);
}
public void VoronoiTest()
{
int count = MersenneTwister.Default.Next(10, 100);
var points = new PointD[count];
for (int i = 0; i < points.Length; i++)
{
points[i] = GeoAlgorithms.RandomPoint(-1000, -1000, 2000, 2000);
}
var results = Voronoi.FindAll(points, new RectD(-1000, -1000, 2000, 2000));
var delaunay = results.ToDelaunySubdivision();
delaunay.Validate();
var voronoi = results.ToVoronoiSubdivision();
voronoi.Source.Validate();
// compare original and subdivision’s Delaunay edges
var delaunayEdges = delaunay.ToLines();
Assert.AreEqual(results.DelaunayEdges.Length, delaunayEdges.Length);
foreach (LineD edge in results.DelaunayEdges)
{
if (PointDComparerY.CompareExact(edge.Start, edge.End) > 0)
{
Assert.Contains(edge.Reverse(), delaunayEdges);
}
else
{
Assert.Contains(edge, delaunayEdges);
}
}
// compare original and subdivision’s Voronoi regions
var voronoiFaces = voronoi.Source.Faces;
Assert.AreEqual(results.VoronoiRegions.Length, voronoiFaces.Count - 1);
foreach (var face in voronoiFaces.Values)
{
if (face.OuterEdge == null)
{
continue;
}
int index = voronoi.FromFace(face);
PointD[] polygon = results.VoronoiRegions[index];
CollectionAssert.AreEquivalent(polygon, face.OuterEdge.CyclePolygon);
PointD site = results.GeneratorSites[index];
Assert.AreNotEqual(PolygonLocation.Outside, face.OuterEdge.Locate(site));
}
}
public static GraphManager <PointD> CreateSubdivisionManager(GraphDialog dialog)
{
RectD output = new RectD(0, 0, dialog.OutputBox.Width, dialog.OutputBox.Height);
RectD bounds = new RectD(8, 8, output.Width - 16, output.Height - 16);
PointD[] points = GeoAlgorithms.RandomPoints(40, bounds, new PointDComparerX(), 20);
VoronoiResults results = Voronoi.FindAll(points, output);
Subdivision division = results.ToDelaunySubdivision(output, true);
var manager = new GraphManager <PointD>(dialog, 8);
manager.Graph = division;
manager.Renderer = new GraphRenderer <PointD>(manager);
// scaling factor to keep step costs above node distance
manager._scaleCost = output.Width + output.Height;
return(manager);
}
private void DrawDiagrams(PointD[] points)
{
RectD bounds = new RectD(0, 0, OutputBox.Width, OutputBox.Height);
// generate new random point set if desired
if (points == null)
{
PointD offset = new PointD(bounds.Width * 0.1, bounds.Height * 0.1);
SizeD scale = new SizeD(bounds.Width * 0.8, bounds.Height * 0.8);
int count = MersenneTwister.Default.Next(4, 20);
points = new PointD[count];
for (int i = 0; i < points.Length; i++)
{
points[i] = new PointD(
offset.X + MersenneTwister.Default.NextDouble() * scale.Width,
offset.Y + MersenneTwister.Default.NextDouble() * scale.Height);
}
}
_points = points;
var result = Voronoi.FindAll(points, bounds);
OutputBox.Children.Clear();
// draw source points
const double radius = 2.0;
for (int i = 0; i < points.Length; i++)
{
Ellipse circle = new Ellipse()
{
Width = 2 * radius, Height = 2 * radius,
Stroke = Brushes.Black,
Fill = Brushes.Black
};
Canvas.SetLeft(circle, points[i].X - radius);
Canvas.SetTop(circle, points[i].Y - radius);
OutputBox.Children.Add(circle);
}
// draw interior of Voronoi regions
foreach (PointD[] region in result.VoronoiRegions)
{
Polygon polygon = new Polygon()
{
Points = region.ToWpfPoints(),
Stroke = Brushes.White,
StrokeThickness = 6.0,
Fill = Brushes.PaleGoldenrod
};
OutputBox.Children.Add(polygon);
}
// draw edges of Voronoi diagram
foreach (VoronoiEdge edge in result.VoronoiEdges)
{
PointD start = result.VoronoiVertices[edge.Vertex1];
PointD end = result.VoronoiVertices[edge.Vertex2];
Line line = new Line()
{
X1 = start.X, Y1 = start.Y,
X2 = end.X, Y2 = end.Y,
Stroke = Brushes.Red
};
OutputBox.Children.Add(line);
}
// draw edges of Delaunay triangulation
foreach (LineD edge in result.DelaunayEdges)
{
Line line = new Line()
{
X1 = edge.Start.X, Y1 = edge.Start.Y,
X2 = edge.End.X, Y2 = edge.End.Y,
Stroke = Brushes.Blue,
StrokeDashArray = { 3.0, 2.0 }
};
OutputBox.Children.Add(line);
}
}
