public void Reorder(int width, int height)
{
//Checks if the site is fully included in the frame :
if (Edges.Select(e => e.VVertexA).All(p => IsVectorInRange(p, width, height)) &&
Edges.Select(e => e.VVertexB).All(p => IsVectorInRange(p, width, height)))
{
IsOnBorder = false;
}
else
{
IsOnBorder = true;
Vector previousIntersection = null;
for (int i = Edges.Count - 1; i >= 0; i--)
{
VoronoiEdge edge = Edges[i];
bool isAIn = IsVectorInRange(edge.VVertexA, width, height);
bool isBIn = IsVectorInRange(edge.VVertexB, width, height);
if (isAIn && isBIn) // Edge is fully in, nothing to do
{
continue;
}
if (isAIn || isBIn) // One point in in, needs to be clipped
{
double slope = edge.DirectionVector[1] / edge.DirectionVector[0];
Vector pointIn = isAIn ? new Vector(edge.VVertexA) : new Vector(edge.VVertexB);
List <Vector> intersections = new List <Vector>();
//Test collision with (0,0) => (width,0) edge :
intersections.Add(new Vector(pointIn[0] - pointIn[1] / slope, 0));
//Test collision with (0,height) => (width,height) edge :
intersections.Add(new Vector(pointIn[0] + (height - pointIn[1]) / slope, height));
//Test collision with (0,0) => (0,height) edge :
intersections.Add(new Vector(0, pointIn[1] - pointIn[0] * slope));
//Test collision with (width,0) => (width,height) edge :
intersections.Add(new Vector(width, pointIn[1] + (width - pointIn[0]) * slope));
Vector intersection = intersections.MinBy(p => Vector.Dist(p, pointIn));
Edges.RemoveAt(i);
Edges.Add(new VoronoiEdge {
VVertexA = intersection, VVertexB = pointIn
});
if (previousIntersection == null)
{
previousIntersection = intersection;
}
else
{
if (intersection[0].Equals(previousIntersection[0]) ||
intersection[1].Equals(previousIntersection[1]))
{
Edges.Add(new VoronoiEdge {
VVertexA = intersection, VVertexB = previousIntersection
});
IsOnBorder = true;
previousIntersection = null;
}
else
{
List <Vector> corners = new List <Vector>
{
new Vector(0, 0),
new Vector(width, 0),
new Vector(width, height),
new Vector(0, height)
};
foreach (Vector corner in corners)
{
if ((corner[0].Equals(previousIntersection[0]) ||
corner[0].Equals(intersection[0])) &&
(corner[1].Equals(previousIntersection[1]) ||
corner[1].Equals(intersection[1])))
{
Edges.Add(new VoronoiEdge {
VVertexA = corner, VVertexB = previousIntersection
});
Edges.Add(new VoronoiEdge {
VVertexA = corner, VVertexB = intersection
});
IsOnBorder = true;
break;
}
}
previousIntersection = null;
}
}
}
else // Edge fully out, can be safely removed
{
Edges.RemoveAt(i);
}
}
if (previousIntersection != null)
{
throw new InvalidOperationException("Error");
}
}
if (Edges.Count == 0)
{
throw new InvalidOperationException("No edges");
}
VoronoiEdge first = Edges[Edges.Count - 1];
Edges.RemoveAt(Edges.Count - 1);
Vector point;
VoronoiPoints.Add(point = first.VVertexA);
Edges.RemoveAll((e) => Equals(e.VVertexA, e.VVertexB));
do
{
VoronoiEdge edge = Edges.Single(e => e.VVertexA.Equals(point) || e.VVertexB.Equals(point));
Edges.Remove(edge);
if (Equals(edge.VVertexA, point))
{
VoronoiPoints.Add(point = edge.VVertexB);
}
else
{
VoronoiPoints.Add(point = edge.VVertexA);
}
} while (!Equals(point, first.VVertexB));
Edges.Clear();
//Reverse ordering of the points if needed :
Vector v1 = VoronoiPoints[0] - VoronoiPoints[1];
Vector v2 = VoronoiCenter - VoronoiPoints[0];
if (v1[0] * v2[1] - v1[1] * v2[0] > 0)
{
VoronoiPoints.Reverse();
}
}
