/// <summary>
/// Whether the two line segments inflect each other.
/// </summary>
/// <param name="lineSegment">the target linesegment</param>
/// <returns>true if inflect</returns>
public bool Inflects(LineSegment2D lineSegment)
{
if (this.TrulyContains(lineSegment.FirstPoint) || this.TrulyContains(lineSegment.LastPoint))
{
if (this.ToVector() * lineSegment.ToVector() < ZeroTolerance)
{
return(true);
}
}
if (this.Contains(lineSegment) || lineSegment.Contains(this))
{
return(true);
}
return(false);
}
/// <summary>
/// Whether the two line segments inflect each other.
/// </summary>
/// <param name="lineSegment">the target linesegment</param>
/// <returns>true if inflect</returns>
public bool Inflects(LineSegment2D lineSegment)
{
if (this.TrulyContains(lineSegment.FirstPoint) || this.TrulyContains(lineSegment.LastPoint))
{
if (this.ToVector() * lineSegment.ToVector() < ZeroTolerance)
{
return true;
}
}
if (this.Contains(lineSegment) || lineSegment.Contains(this))
{
return true;
}
return false;
}
/// <summary>
/// Construct a minimum link path of a polygon.
/// </summary>
public void BuildPath()
{
this.LinkDivisers.Clear();
Point2D CurrentPoint = this.LastPoint;
Point2D IntersectPoint = null;
LineSegment2D CurrentLine = null;
LineSegment2D IntersectLine = null;
for (int i = this.Divisers.Count - 1; i >= 0; i--)
{
double position = -1.0;
Polygon2D currentPolygon = this.SubDivision[i + 1];
CurrentLine = this.Divisers[i];
if (CurrentLine.Contains(CurrentPoint))
{
this.LinkDivisers.Add(CurrentPoint);
Vector2D vector = CurrentLine.ToVector().Normal().Normalize();
IntersectPoint = CurrentLine.MidPoint + vector;
if (!this.SubDivision[i].Contains(IntersectPoint))
{
vector = -vector;
}
double length = CurrentLine.Length;
LineSegment2D testLine = null;
do
{
IntersectPoint = CurrentLine.MidPoint + vector * length;
length /= 2;
testLine = new LineSegment2D(CurrentPoint, IntersectPoint);
} while (!this.SubDivision[i].Contains(testLine));
continue;
}
for (int j = 0; j < currentPolygon.VertexCount; j++)
{
Point2D point = currentPolygon.GetPoint(j);
if (CurrentPoint == point)
{
continue;
}
LineSegment2D lineSegment = new LineSegment2D(CurrentPoint, point);
if (currentPolygon.Contains(lineSegment) || currentPolygon.isEdge(lineSegment))
{
if (CurrentLine.LineIntersects(lineSegment))
{
IntersectPoint = CurrentLine.ToLine().Intersects(lineSegment.ToLine());
if (position < 0)
{
position = CurrentLine.GetPosition(IntersectPoint);
}
else
{
position += CurrentLine.GetPosition(IntersectPoint);
position /= 2;
}
}
}
}
if (position < -0.5)
{
CurrentPoint = IntersectPoint + IntersectLine.ToVector().Normalize();
i++;
continue;
}
this.LinkDivisers.Add(CurrentPoint);
IntersectPoint = CurrentLine.GetPoint(position);
IntersectLine = new LineSegment2D(CurrentPoint, IntersectPoint);
double extend = IntersectLine.Length;
do
{
extend /= 2;
CurrentPoint = IntersectLine.Extend(extend);
} while (!this.SubDivision[i].Contains(CurrentPoint));
//CurrentPoint = CurrentLine.GetPoint(position);
}
CurrentLine = new LineSegment2D(CurrentPoint, this.FirstPoint);
if (this.Parent.Contains(CurrentLine))
{
this.LinkDivisers.Add(CurrentPoint);
this.LinkDivisers.Add(this.FirstPoint);
}
else if (IntersectLine != null)
{
CurrentPoint = IntersectPoint + IntersectLine.ToVector().Normalize();
this.LinkDivisers.Add(CurrentPoint);
this.LinkDivisers.Add(this.FirstPoint);
}
else
{
Vector2D vector = CurrentLine.ToVector().Normal().Normalize();
IntersectPoint = CurrentLine.MidPoint + vector;
if (!this.Parent.Contains(IntersectPoint))
{
vector = -vector;
}
IntersectPoint = CurrentLine.MidPoint;
double length = CurrentLine.Length;
do
{
length /= 2;
CurrentPoint = IntersectPoint + vector * length;
}
while (!this.Parent.Contains(CurrentPoint));
this.LinkDivisers.Add(this.LastPoint);
this.LinkDivisers.Add(CurrentPoint);
this.LinkDivisers.Add(this.FirstPoint);
}
}
/// <summary>
/// Construct a minimum link path of a polygon.
/// </summary>
public void BuildPath()
{
this.LinkDivisers.Clear();
Point2D CurrentPoint = this.LastPoint;
Point2D IntersectPoint = null;
LineSegment2D CurrentLine = null;
LineSegment2D IntersectLine = null;
for (int i = this.Divisers.Count - 1; i >= 0; i--)
{
double position = -1.0;
Polygon2D currentPolygon = this.SubDivision[i + 1];
CurrentLine = this.Divisers[i];
if (CurrentLine.Contains(CurrentPoint))
{
this.LinkDivisers.Add(CurrentPoint);
Vector2D vector = CurrentLine.ToVector().Normal().Normalize();
IntersectPoint = CurrentLine.MidPoint + vector;
if (!this.SubDivision[i].Contains(IntersectPoint))
{
vector = -vector;
}
double length = CurrentLine.Length;
LineSegment2D testLine = null;
do
{
IntersectPoint = CurrentLine.MidPoint + vector * length;
length /= 2;
testLine = new LineSegment2D(CurrentPoint, IntersectPoint);
} while (!this.SubDivision[i].Contains(testLine));
continue;
}
for (int j = 0; j < currentPolygon.VertexCount; j++)
{
Point2D point = currentPolygon.GetPoint(j);
if (CurrentPoint == point)
{
continue;
}
LineSegment2D lineSegment = new LineSegment2D(CurrentPoint, point);
if (currentPolygon.Contains(lineSegment) || currentPolygon.isEdge(lineSegment))
{
if (CurrentLine.LineIntersects(lineSegment))
{
IntersectPoint = CurrentLine.ToLine().Intersects(lineSegment.ToLine());
if (position < 0)
{
position = CurrentLine.GetPosition(IntersectPoint);
}
else
{
position += CurrentLine.GetPosition(IntersectPoint);
position /= 2;
}
}
}
}
if (position < -0.5)
{
CurrentPoint = IntersectPoint + IntersectLine.ToVector().Normalize();
i++;
continue;
}
this.LinkDivisers.Add(CurrentPoint);
IntersectPoint = CurrentLine.GetPoint(position);
IntersectLine = new LineSegment2D(CurrentPoint, IntersectPoint);
double extend = IntersectLine.Length;
do
{
extend /= 2;
CurrentPoint = IntersectLine.Extend(extend);
} while (!this.SubDivision[i].Contains(CurrentPoint));
//CurrentPoint = CurrentLine.GetPoint(position);
}
CurrentLine = new LineSegment2D(CurrentPoint, this.FirstPoint);
if (this.Parent.Contains(CurrentLine))
{
this.LinkDivisers.Add(CurrentPoint);
this.LinkDivisers.Add(this.FirstPoint);
}
else if (IntersectLine != null)
{
CurrentPoint = IntersectPoint + IntersectLine.ToVector().Normalize();
this.LinkDivisers.Add(CurrentPoint);
this.LinkDivisers.Add(this.FirstPoint);
}
else
{
Vector2D vector = CurrentLine.ToVector().Normal().Normalize();
IntersectPoint = CurrentLine.MidPoint + vector;
if (!this.Parent.Contains(IntersectPoint))
{
vector = -vector;
}
IntersectPoint = CurrentLine.MidPoint;
double length = CurrentLine.Length;
do
{
length /= 2;
CurrentPoint = IntersectPoint + vector * length;
}while (!this.Parent.Contains(CurrentPoint));
this.LinkDivisers.Add(this.LastPoint);
this.LinkDivisers.Add(CurrentPoint);
this.LinkDivisers.Add(this.FirstPoint);
}
}
private void Divide(Polygon2D poly)
{
for (int i = 0; i < poly.VertexCount; i++) //Find Convex Angle
{
if (poly.isConvexAngle(i))
{
continue;
}
int index = i;
double min_dist = 10000;
for (int j = 0; j < poly.VertexCount; j++) //Divide Polygon
{
if (j == i)
{
continue;
}
LineSegment2D line = new LineSegment2D(poly.GetPoint(i), poly.GetPoint(j));
if (poly.isDiagonal(line))
{
//double dist = line.Length;
Vector2D v1 = line.ToVector();
LineSegment2D line1 = poly.GetEdge(i);
line1.SwapPoints();
LineSegment2D line2 = poly.GetEdge((i + 1) % poly.VertexCount);
Vector2D v2 = line1.ToVector();
Vector2D v3 = line2.ToVector();
double angle1 = Vector2D.Angle(v2, v1);
double angle2 = Vector2D.Angle(v1, v3); //ѡȡ���ֽǶ�����ȵĵ����ָ��
if (angle1 < 0)
{
angle1 += Math.PI * 2;
}
if (angle2 < 0)
{
angle2 += Math.PI * 2;
}
double dist = Math.Max(angle1, angle2);
if (!poly.isConvexAngle(j) && dist < Math.PI)
{
dist -= Math.PI;
}
if(dist < min_dist)
{
index = j;
min_dist = dist;
}
}
}
if (index != i)
{
this.DividedBy(new LineSegment2D(poly.GetPoint(i), poly.GetPoint(index)));
return;
}
}
throw (new ArgumentException());
}