public bool Intersects(LineF2D line)
{
PointF2D[] corners = this.Corners;
LinePointPosition linePointPosition = line.PositionOfPoint(corners[0]);
for (int index = 1; index <= corners.Length; ++index)
{
if (line.PositionOfPoint(corners[index]) != linePointPosition)
{
return(true);
}
}
return(false);
}
public bool Intersects(PointF2D point1, PointF2D point2)
{
PointF2D[] corners = this.Corners;
LineF2D lineF2D = new LineF2D(point1, point2, true);
LinePointPosition linePointPosition = lineF2D.PositionOfPoint(corners[0]);
for (int index = 1; index < corners.Length; ++index)
{
if (lineF2D.PositionOfPoint(corners[index]) != linePointPosition)
{
return(true);
}
}
return(false);
}
/// <summary>
/// Returns true if the line intersects with this bounding box.
/// </summary>
/// <param name="line"></param>
/// <returns></returns>
public bool Intersects(LineF2D line)
{
// if all points have the same relative position with respect to the line
// there is no intersection. In the other case there is.
PointF2D[] corners = this.Corners;
LinePointPosition first_position = line.PositionOfPoint(corners[0]);
for (int idx = 1; idx <= corners.Length; idx++)
{
if (line.PositionOfPoint(corners[idx]) != first_position)
{
return(true);
}
}
return(false);
}
/// <summary>
/// Returns true if the given coordinate is contained in this ring.
///
/// See: http://geomalgorithms.com/a03-_inclusion.html
/// </summary>
/// <param name="coordinate"></param>
/// <returns></returns>
public bool Contains(double[] coordinate)
{
int number = 0;
if (this.X[0] == coordinate[0] &&
this.Y[0] == coordinate[1])
{ // the given point is one of the corners.
return true;
}
// loop over all edges and calculate if they possibly intersect.
for (int idx = 0; idx < this.X.Length - 1; idx++)
{
if (this.X[idx + 1] == coordinate[0] &&
this.Y[idx + 1] == coordinate[1])
{ // the given point is one of the corners.
return true;
}
bool idxRight = this.X[idx] > coordinate[0];
bool idx1Right = this.X[idx + 1] > coordinate[0];
if (idxRight || idx1Right)
{ // at least one of the coordinates is to the right of the point to calculate for.
if ((this.Y[idx] <= coordinate[1] &&
this.Y[idx + 1] >= coordinate[1]) &&
!(this.Y[idx] == coordinate[1] &&
this.Y[idx + 1] == coordinate[1]))
{ // idx is lower than idx+1
if (idxRight && idx1Right)
{ // no need for the left/right algorithm the result is already known.
number++;
}
else
{ // one of the coordinates is not to the 'right' now we need the left/right algorithm.
LineF2D localLine = new LineF2D(
new PointF2D(this.X[idx], this.Y[idx]),
new PointF2D(this.X[idx + 1], this.Y[idx + 1]));
if (localLine.PositionOfPoint(new PointF2D(coordinate)) == LinePointPosition.Left)
{
number++;
}
}
}
else if ((this.Y[idx] >= coordinate[1] &&
this.Y[idx + 1] <= coordinate[1]) &&
!(this.Y[idx] == coordinate[1] &&
this.Y[idx + 1] == coordinate[1]))
{ // idx is higher than idx+1
if (idxRight && idx1Right)
{ // no need for the left/right algorithm the result is already known.
number--;
}
else
{ // one of the coordinates is not to the 'right' now we need the left/right algorithm.
LineF2D localLine = new LineF2D(
new PointF2D(this.X[idx], this.Y[idx]),
new PointF2D(this.X[idx + 1], this.Y[idx + 1]));
if (localLine.PositionOfPoint(new PointF2D(coordinate)) == LinePointPosition.Right)
{
number--;
}
}
}
}
}
return number != 0;
}
/// <summary>
/// Returns true if the given coordinate is contained in this ring.
///
/// See: http://geomalgorithms.com/a03-_inclusion.html
/// </summary>
/// <param name="coordinate"></param>
/// <returns></returns>
public bool Contains(GeoCoordinate coordinate)
{
int number = 0;
if (this.Coordinates[0] == coordinate)
{ // the given point is one of the corners.
return true;
}
// loop over all edges and calculate if they possibly intersect.
for (int idx = 0; idx < this.Coordinates.Count - 1; idx++)
{
if (this.Coordinates[idx + 1] == coordinate)
{ // the given point is one of the corners.
return true;
}
bool idxRight = this.Coordinates[idx].Longitude > coordinate.Longitude;
bool idx1Right = this.Coordinates[idx + 1].Longitude > coordinate.Longitude;
if (idxRight || idx1Right)
{ // at least on of the coordinates is to the right of the point to calculate for.
if ((this.Coordinates[idx].Latitude <= coordinate.Latitude &&
this.Coordinates[idx + 1].Latitude >= coordinate.Latitude) &&
!(this.Coordinates[idx].Latitude == coordinate.Latitude &&
this.Coordinates[idx + 1].Latitude == coordinate.Latitude))
{ // idx is lower than idx+1
if (idxRight && idx1Right)
{ // no need for the left/right algorithm the result is already known.
number++;
}
else
{ // one of the coordinates is not to the 'right' now we need the left/right algorithm.
LineF2D localLine = new LineF2D(this.Coordinates[idx], this.Coordinates[idx + 1]);
if (localLine.PositionOfPoint(coordinate) == LinePointPosition.Left)
{
number++;
}
}
}
else if ((this.Coordinates[idx].Latitude >= coordinate.Latitude &&
this.Coordinates[idx + 1].Latitude <= coordinate.Latitude) &&
!(this.Coordinates[idx].Latitude == coordinate.Latitude &&
this.Coordinates[idx + 1].Latitude == coordinate.Latitude))
{ // idx is higher than idx+1
if (idxRight && idx1Right)
{ // no need for the left/right algorithm the result is already known.
number--;
}
else
{ // one of the coordinates is not to the 'right' now we need the left/right algorithm.
LineF2D localLine = new LineF2D(this.Coordinates[idx], this.Coordinates[idx + 1]);
if (localLine.PositionOfPoint(coordinate) == LinePointPosition.Right)
{
number--;
}
}
}
}
}
return number != 0;
}
public void LinePosition2DTest()
{
PointF2D a = new PointF2D(0, 0);
PointF2D b = new PointF2D(1, 1);
LineF2D line = new LineF2D(a, b);
// test where the position lie.
Assert.AreEqual(line.PositionOfPoint(new PointF2D(0, 0.5f)), LinePointPosition.Left, "Point position should be right!");
Assert.AreEqual(line.PositionOfPoint(new PointF2D(0.5f, 0.5f)), LinePointPosition.On, "Point position should be on!");
Assert.AreEqual(line.PositionOfPoint(new PointF2D(0.5f, 0)), LinePointPosition.Right, "Point position should be left!");
}
