/// <summary>
/// Computes whether the given coordinate is on the boundary of the polygon.
/// </summary>
/// <param name="shell">The polygon shell.</param>
/// <param name="coordinate">The coordinate to check.</param>
/// <param name="precisionModel">The precision model.</param>
/// <returns><c>true</c> if the coordinate is on the boundary of the polygon; otherwise, <c>false</c>.</returns>
/// <exception cref="System.ArgumentNullException">The shell is null.</exception>
private static Boolean ComputeOnBoundary(IEnumerable <Coordinate> shell, Coordinate coordinate, PrecisionModel precisionModel)
{
IEnumerator <Coordinate> enumerator = shell.GetEnumerator();
if (!enumerator.MoveNext())
{
return(false);
}
Coordinate current = enumerator.Current, next;
while (enumerator.MoveNext())
{
next = enumerator.Current;
if (LineAlgorithms.Contains(current, next, coordinate, precisionModel))
{
return(true);
}
current = next;
}
return(false);
}
/// <summary>
/// Checks whether the given coordinate is on the shell.
/// </summary>
private void CheckBoundary()
{
IsOnBoundary = false;
for (Int32 coordIndex = 0; coordIndex < _shell.Count - 1 || (coordIndex < _shell.Count && _shell[0] != _shell[_shell.Count - 1]); coordIndex++)
{
if (LineAlgorithms.Contains(_shell[coordIndex], _shell[(coordIndex + 1) % _shell.Count], _coordinate, PrecisionModel))
{
IsOnBoundary = true;
break;
}
}
}
public void LineAlgorithmsContainsTest()
{
// line contains point
Coordinate lineStart = new Coordinate(0, 1);
Coordinate lineEnd = new Coordinate(100, 1);
Coordinate coordinate = new Coordinate(1, 1);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate));
lineStart = new Coordinate(0, 0);
lineEnd = new Coordinate(2, 2);
coordinate = new Coordinate(1, 1);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate));
lineStart = new Coordinate(0, 0);
lineEnd = new Coordinate(-4, 2);
coordinate = new Coordinate(-2, 1);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate));
coordinate = new Coordinate(-1, 0.5);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate));
// line does not contain point
lineStart = new Coordinate(0, 0);
lineEnd = new Coordinate(2, 2);
coordinate = new Coordinate(1, 1.2);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineEnd, coordinate));
lineStart = new Coordinate(0, 0);
lineEnd = new Coordinate(0, 200);
coordinate = new Coordinate(0, 201);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineEnd, coordinate));
lineStart = new Coordinate(0, 0);
lineEnd = new Coordinate(0, 200);
coordinate = new Coordinate(0, 201);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineEnd, coordinate));
// infinite line contains point
lineStart = new Coordinate(2, 5);
CoordinateVector lineVector = new CoordinateVector(0, 1);
coordinate = new Coordinate(2, 4);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineVector, coordinate));
coordinate = new Coordinate(2, 400);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineVector, coordinate));
lineStart = new Coordinate(2, 4);
lineVector = new CoordinateVector(-3, 1);
coordinate = new Coordinate(14, 0);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineVector, coordinate));
// infinite line does not contain point
coordinate = new Coordinate(2.001, 400);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineVector, coordinate));
lineStart = new Coordinate(1, 1);
lineVector = new CoordinateVector(0, 2);
coordinate = new Coordinate(0, 101);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineVector, coordinate));
// finite line with fixed precision
PrecisionModel precision = new PrecisionModel(0.001);
lineStart = new Coordinate(0, 0);
lineEnd = new Coordinate(2000, 2000);
coordinate = new Coordinate(1000, 1000);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate, precision));
lineStart = new Coordinate(0, 0);
lineEnd = new Coordinate(-4000, 2000);
coordinate = new Coordinate(-3000, 2000);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate, precision));
coordinate = new Coordinate(-3000, 1000);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate, precision));
// finite line at given fixed precision
lineStart = new Coordinate(12, 201);
lineEnd = new Coordinate(1870, 2390);
coordinate = new Coordinate(980, 1110);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate, precision));
lineStart = new Coordinate(-20, 50);
lineEnd = new Coordinate(-4102, 1960);
coordinate = new Coordinate(-2111, 983);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate, precision));
lineStart = new Coordinate(-20, 50);
lineEnd = new Coordinate(-4102, 1960);
coordinate = new Coordinate(-2111, 983);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineEnd, coordinate, precision));
// infinite line with fixed precision
lineStart = new Coordinate(1000, 1000);
lineVector = new CoordinateVector(0, 2000);
coordinate = new Coordinate(1000, 0);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineVector, coordinate, precision));
coordinate = new Coordinate(0, 0);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineVector, coordinate, precision));
coordinate = new Coordinate(2000, 0);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineVector, coordinate, precision));
// infinite at given fixed precision
lineStart = new Coordinate(1260, 1440);
lineVector = new CoordinateVector(0, 2035);
coordinate = new Coordinate(1230, 0);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineVector, coordinate, precision));
coordinate = new Coordinate(1759, 0);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineVector, coordinate, precision));
coordinate = new Coordinate(761, 0);
Assert.IsTrue(LineAlgorithms.Contains(lineStart, lineVector, coordinate, precision));
coordinate = new Coordinate(759, 0);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineVector, coordinate, precision));
coordinate = new Coordinate(1761, 0);
Assert.IsFalse(LineAlgorithms.Contains(lineStart, lineVector, coordinate, precision));
}