private void Window_Activated_1(object sender, EventArgs e)
{
var pol1 = new MyPolygon(new List<Vector>() {
new Vector(0,3),
new Vector(3,6),
new Vector(6,3),
new Vector(3,0)});
var pol2 = new MyPolygon(new List<Vector>() {
new Vector(4,0),
new Vector(15, 5),
new Vector(15,1)});
DrawPolygon(pol1, Colors.LightSalmon);
DrawPolygon(pol2, Colors.HotPink);
MyPolygon pol3;
try
{
pol3 = MyPolygon.Intersection(pol1, pol2);
}
catch (DisjointPolygons)
{
return;
}
DrawPolygon(pol3, Colors.DarkBlue);
}
public void DrawPolygon(MyPolygon poly, Color fill)
{
var polygon = new Polygon();
polygon.Points = new PointCollection(poly.Points.Select(a => new Point(Math.Round(a.X * step + canvasSize / 2),
Math.Round(-a.Y * step + canvasSize / 2))));
polygon.Stroke = Brushes.Black;
polygon.Fill = new SolidColorBrush(fill);
polygon.StrokeThickness = 1;
canvas.Children.Add(polygon);
}
public static MyPolygon Intersection(MyPolygon a, MyPolygon b)
{
b.points.Add(b.points.First());
for (int i = 0; i < b.points.Count - 1; i++)
{
a = Intersection(a, new Segment(b.points[i], b.points[i + 1]));
if (a.Points.Count == 0)
throw new DisjointPolygons();
}
return a;
}
public static MyPolygon Intersection(MyPolygon a, Segment b)
{
List<Vector> result = new List<Vector>();
a.points.Add(a.points.First());
for (int i = 0; i < a.points.Count - 1; i++)
{
Vector start = a.points[i];
Vector end = a.points[i + 1];
bool s = b.PlaceOfPoint(start) <= 0; //справа
bool e = b.PlaceOfPoint(end) <= 0;
if (s)
result.Add(start);
if (s ^ e)
result.Add(b.CrossingPoint(new Segment(start, end)));
}
return new MyPolygon(result);
}
