public void Equals()
{
var c1 = new Coordinate<int>(13, 14);
var c2 = new Coordinate<int>(c1);
var c3 = new Coordinate<int>(23, 24);
Assert.IsTrue(c1.Equals(c2));
Assert.IsFalse(c1.Equals(c3));
}
/// <summary>
///
/// </summary>
/// <param name="p"></param>
/// <param name="p1"></param>
/// <param name="p2"></param>
public override void ComputeIntersection(Coordinate p, Coordinate p1, Coordinate p2)
{
double a1;
double b1;
double c1;
/*
* Coefficients of line eqns.
*/
double r;
/*
* 'Sign' values
*/
IsProper = false;
/*
* Compute a1, b1, c1, where line joining points 1 and 2
* is "a1 x + b1 y + c1 = 0".
*/
a1 = p2.Y - p1.Y;
b1 = p1.X - p2.X;
c1 = p2.X * p1.Y - p1.X * p2.Y;
/*
* Compute r3 and r4.
*/
r = a1 * p.X + b1 * p.Y + c1;
// if r != 0 the point does not lie on the line
if (r != 0)
{
Result = NoIntersection;
return;
}
// Point lies on line - check to see whether it lies in line segment.
double dist = RParameter(p1, p2, p);
if (dist < 0.0 || dist > 1.0)
{
Result = NoIntersection;
return;
}
IsProper = true;
if (p.Equals(p1) || p.Equals(p2))
IsProper = false;
Result = PointIntersection;
}
public void DifferentTypes()
{
var c1 = new Coordinate<int>(13, 14);
var c2 = new Coordinate<double>(13, 14);
Assert.IsFalse(c1.Equals(c2));
}
/// <summary>
/// Computes the "edge distance" of an intersection point p along a segment.
/// The edge distance is a metric of the point along the edge.
/// The metric used is a robust and easy to compute metric function.
/// It is not equivalent to the usual Euclidean metric.
/// It relies on the fact that either the x or the y ordinates of the
/// points in the edge are unique, depending on whether the edge is longer in
/// the horizontal or vertical direction.
/// NOTE: This function may produce incorrect distances
/// for inputs where p is not precisely on p1-p2
/// (E.g. p = (139,9) p1 = (139,10), p2 = (280,1) produces distanct 0.0, which is incorrect.
/// My hypothesis is that the function is safe to use for points which are the
/// result of rounding points which lie on the line, but not safe to use for truncated points.
/// </summary>
public static double ComputeEdgeDistance(Coordinate p, Coordinate p0, Coordinate p1)
{
var dx = Math.Abs(p1.X - p0.X);
var dy = Math.Abs(p1.Y - p0.Y);
var dist = -1.0; // sentinel value
if (p.Equals(p0))
dist = 0.0;
else if (p.Equals(p1))
{
dist = dx > dy ? dx : dy;
}
else
{
double pdx = Math.Abs(p.X - p0.X);
double pdy = Math.Abs(p.Y - p0.Y);
dist = dx > dy ? pdx : pdy;
// <FIX>: hack to ensure that non-endpoints always have a non-zero distance
if (dist == 0.0 && ! p.Equals2D(p0))
dist = Math.Max(pdx, pdy);
}
Assert.IsTrue(!(dist == 0.0 && ! p.Equals(p0)), "Bad distance calculation");
return dist;
}
/// <summary>
///
/// </summary>
/// <param name="p"></param>
/// <param name="p1"></param>
/// <param name="p2"></param>
public override void ComputeIntersection(Coordinate p, Coordinate p1, Coordinate p2)
{
IsProper = false;
// do between check first, since it is faster than the orientation test
if(Envelope.Intersects(p1, p2, p))
{
if((CGAlgorithms.OrientationIndex(p1, p2, p) == 0) && (CGAlgorithms.OrientationIndex(p2, p1, p) == 0))
{
IsProper = true;
if (p.Equals(p1) || p.Equals(p2))
IsProper = false;
Result = IntersectionTypes.PointIntersection;
return;
}
}
Result = IntersectionTypes.NoIntersection;
}
/// <summary>
/// Automatically closes the ring (if it not alread is).
/// </summary>
public void CloseRing()
{
if (_ptList.Count < 1) return;
var startPt = new Coordinate(_ptList[0]);
var lastPt = _ptList[_ptList.Count - 1];
/*Coordinate last2Pt = null;
if (ptList.Count >= 2)
last2Pt = (Coordinate)ptList[ptList.Count - 2];*/
if (startPt.Equals(lastPt)) return;
_ptList.Add(startPt);
}
public void TestEquals()
{
Coordinate c1 = new Coordinate(1, 2, 3);
const string s = "Not a coordinate";
Assert.IsFalse(c1.Equals(s));
Coordinate c2 = new Coordinate(1, 2, 3);
Assert.IsTrue(c1.Equals2D(c2));
Coordinate c3 = new Coordinate(1, 22, 3);
Assert.IsFalse(c1.Equals2D(c3));
}
public void DiffCoordinateNotEquals()
{
//arrange
Coordinate first = new Coordinate(1, 1);
Coordinate second = new Coordinate(2, 2);
bool expected = false;
//act
bool actual = first.Equals(second);
//assert
Assert.AreEqual(expected, actual);
}
/// <summary>
/// This function is non-robust, since it may compute the square of large numbers.
/// Currently not sure how to improve this.
/// </summary>
public static double NonRobustComputeEdgeDistance(Coordinate p, Coordinate p1, Coordinate p2)
{
double dx = p.X - p1.X;
double dy = p.Y - p1.Y;
double dist = Math.Sqrt(dx * dx + dy * dy); // dummy value
Assert.IsTrue(! (dist == 0.0 && ! p.Equals(p1)), "Invalid distance calculation");
return dist;
}
/// <summary>
/// Tests whether the segment p0-p1 intersects the hot pixel tolerance square.
/// Because the tolerance square point set is partially open (along the
/// top and right) the test needs to be more sophisticated than
/// simply checking for any intersection. However, it
/// can take advantage of the fact that because the hot pixel edges
/// do not lie on the coordinate grid. It is sufficient to check
/// if there is at least one of:
/// - a proper intersection with the segment and any hot pixel edge.
/// - an intersection between the segment and both the left and bottom edges.
/// - an intersection between a segment endpoint and the hot pixel coordinate.
/// </summary>
/// <param name="p0"></param>
/// <param name="p1"></param>
/// <returns></returns>
private bool IntersectsToleranceSquare(Coordinate p0, Coordinate p1)
{
bool intersectsLeft = false;
bool intersectsBottom = false;
_li.ComputeIntersection(p0, p1, _corner[0], _corner[1]);
if (_li.IsProper) return true;
_li.ComputeIntersection(p0, p1, _corner[1], _corner[2]);
if (_li.IsProper) return true;
if (_li.HasIntersection) intersectsLeft = true;
_li.ComputeIntersection(p0, p1, _corner[2], _corner[3]);
if (_li.IsProper) return true;
if (_li.HasIntersection) intersectsBottom = true;
_li.ComputeIntersection(p0, p1, _corner[3], _corner[0]);
if (_li.IsProper) return true;
if (intersectsLeft && intersectsBottom) return true;
if (p0.Equals(_pt)) return true;
if (p1.Equals(_pt)) return true;
return false;
}
private void doTestCoordinateHash(bool equal, Coordinate a, Coordinate b) {
Assert.AreEqual(equal, a.Equals(b));
Assert.AreEqual(equal, a.GetHashCode() == b.GetHashCode());
}
/// <summary>
///
/// </summary>
/// <param name="p1"></param>
/// <param name="p2"></param>
/// <param name="p3"></param>
/// <param name="p4"></param>
/// <returns></returns>
public override IntersectionTypes ComputeIntersect(Coordinate p1, Coordinate p2, Coordinate p3, Coordinate p4)
{
/*
* Coefficients of line eqns.
*/
/*
* 'Sign' values
*/
IsProper = false;
/*
* Compute a1, b1, c1, where line joining points 1 and 2
* is "a1 x + b1 y + c1 = 0".
*/
double a1 = p2.Y - p1.Y;
double b1 = p1.X - p2.X;
double c1 = p2.X * p1.Y - p1.X * p2.Y;
/*
* Compute r3 and r4.
*/
double r3 = a1 * p3.X + b1 * p3.Y + c1;
double r4 = a1 * p4.X + b1 * p4.Y + c1;
/*
* Check signs of r3 and r4. If both point 3 and point 4 lie on
* same side of line 1, the line segments do not intersect.
*/
if (r3 != 0 && r4 != 0 && IsSameSignAndNonZero(r3, r4))
{
return IntersectionTypes.NoIntersection;
}
/*
* Compute a2, b2, c2
*/
double a2 = p4.Y - p3.Y;
double b2 = p3.X - p4.X;
double c2 = p4.X * p3.Y - p3.X * p4.Y;
/*
* Compute r1 and r2
*/
double r1 = a2 * p1.X + b2 * p1.Y + c2;
double r2 = a2 * p2.X + b2 * p2.Y + c2;
/*
* Check signs of r1 and r2. If both point 1 and point 2 lie
* on same side of second line segment, the line segments do
* not intersect.
*/
if (r1 != 0 && r2 != 0 && IsSameSignAndNonZero(r1, r2))
{
return IntersectionTypes.NoIntersection;
}
/*
* Line segments intersect: compute intersection point.
*/
double denom = a1 * b2 - a2 * b1;
if (denom == 0)
return ComputeCollinearIntersection(p1, p2, p3, p4);
double numX = b1 * c2 - b2 * c1;
double x = numX / denom;
double numY = a2 * c1 - a1 * c2;
double y = numY / denom;
PointA = new Coordinate(x, y);
// check if this is a proper intersection BEFORE truncating values,
// to avoid spurious equality comparisons with endpoints
IsProper = true;
if (PointA.Equals(p1) || PointA.Equals(p2) || PointA.Equals(p3) || PointA.Equals(p4))
IsProper = false;
// truncate computed point to precision grid
if (PrecisionModel != null)
PrecisionModel.MakePrecise(PointA);
return IntersectionTypes.PointIntersection;
}
/// <summary>Computes the Projection Factor for the projection of the point p
/// onto this LineSegment. The Projection Factor is the constant r
/// by which the vector for this segment must be multiplied to
/// equal the vector for the projection of <tt>p</tt> on the line
/// defined by this segment.
/// <para/>
/// The projection factor will lie in the range <tt>(-inf, +inf)</tt>,
/// or be <c>NaN</c> if the line segment has zero length.
/// </summary>
/// <param name="p">The point to compute the factor for</param>
/// <returns>The projection factor for the point</returns>
public double ProjectionFactor(Coordinate p)
{
if (p.Equals(_p0)) return 0.0;
if (p.Equals(_p1)) return 1.0;
// Otherwise, use comp.graphics.algorithms Frequently Asked Questions method
/* AC dot AB
r = ------------
||AB||^2
r has the following meaning:
r=0 Point = A
r=1 Point = B
r<0 Point is on the backward extension of AB
r>1 Point is on the forward extension of AB
0<r<1 Point is interior to AB
*/
var dx = _p1.X - _p0.X;
var dy = _p1.Y - _p0.Y;
var len = dx * dx + dy * dy;
// handle zero-length segments
if (len <= 0.0) return Double.NaN;
double r = ((p.X - _p0.X) * dx + (p.Y - _p0.Y) * dy)
/ len;
return r;
}
/// <summary>
/// Compute the projection factor for the projection of the point p
/// onto this <c>LineSegment</c>. The projection factor is the constant k
/// by which the vector for this segment must be multiplied to
/// equal the vector for the projection of p.
/// </summary>
/// <param name="p"></param>
/// <returns></returns>
public virtual double ProjectionFactor(Coordinate p)
{
if (p.Equals(P0)) return 0.0;
if (p.Equals(P1)) return 1.0;
// Otherwise, use comp.graphics.algorithms Frequently Asked Questions method
/* AC dot AB
r = ------------
||AB||^2
r has the following meaning:
r=0 Point = A
r=1 Point = B
r<0 Point is on the backward extension of AB
r>1 Point is on the forward extension of AB
0<r<1 Point is interior to AB
*/
double dx = P1.X - P0.X;
double dy = P1.Y - P0.Y;
double len2 = dx * dx + dy * dy;
double r = ((p.X - P0.X) * dx + (p.Y - P0.Y) * dy) / len2;
return r;
}
public static bool IsInList(Coordinate pt, Coordinate[] pts)
{
foreach (Coordinate p in pts)
if (pt.Equals(p))
return true;
return true;
}
private static void CheckCollapse(Coordinate p0, Coordinate p1, Coordinate p2)
{
if (p0.Equals(p2))
throw new ApplicationException(String.Format(
"found non-noded collapse at: {0}, {1} {2}", p0, p1, p2));
}
/// <summary>
///
/// </summary>
/// <param name="p0"></param>
/// <param name="p1"></param>
/// <param name="p2"></param>
private static void CheckCollapse(Coordinate p0, Coordinate p1, Coordinate p2)
{
if (p0.Equals(p2))
throw new Exception("found non-noded collapse at: " + p0 + ", " + p1 + " " + p2);
}
/// <summary>
/// Computes the distance from a line segment AB to a line segment CD.
/// Note: NON-ROBUST!
/// </summary>
/// <param name="A">A point of one line.</param>
/// <param name="B">The second point of the line (must be different to A).</param>
/// <param name="C">One point of the line.</param>
/// <param name="D">Another point of the line (must be different to A).</param>
/// <returns>The distance from line segment AB to line segment CD.</returns>
public static double DistanceLineLine(Coordinate A, Coordinate B, Coordinate C, Coordinate D)
{
// check for zero-length segments
if (A.Equals(B))
return DistancePointLine(A,C,D);
if (C.Equals(D))
return DistancePointLine(D,A,B);
// AB and CD are line segments
/* from comp.graphics.algo
Solving the above for r and s yields
(Ay-Cy)(Dx-Cx)-(Ax-Cx)(Dy-Cy)
r = ----------------------------- (eqn 1)
(Bx-Ax)(Dy-Cy)-(By-Ay)(Dx-Cx)
(Ay-Cy)(Bx-Ax)-(Ax-Cx)(By-Ay)
s = ----------------------------- (eqn 2)
(Bx-Ax)(Dy-Cy)-(By-Ay)(Dx-Cx)
Let Point be the position vector of the intersection point, then
Point=A+r(B-A) or
Px=Ax+r(Bx-Ax)
Py=Ay+r(By-Ay)
By examining the values of r & s, you can also determine some other
limiting conditions:
If 0<=r<=1 & 0<=s<=1, intersection exists
r<0 or r>1 or s<0 or s>1 line segments do not intersect
If the denominator in eqn 1 is zero, AB & CD are parallel
If the numerator in eqn 1 is also zero, AB & CD are collinear.
*/
double r_top = (A.Y - C.Y) * (D.X - C.X) - (A.X - C.X) * (D.Y - C.Y);
double r_bot = (B.X - A.X) * (D.Y - C.Y) - (B.Y - A.Y) * (D.X - C.X);
double s_top = (A.Y - C.Y) * (B.X - A.X) - (A.X - C.X) * (B.Y - A.Y);
double s_bot = (B.X - A.X) * (D.Y - C.Y) - (B.Y - A.Y) * (D.X - C.X);
if ((r_bot==0) || (s_bot == 0))
return Math.Min(DistancePointLine(A,C,D),
Math.Min(DistancePointLine(B,C,D),
Math.Min(DistancePointLine(C,A,B),
DistancePointLine(D,A,B) ) ) );
double s = s_top/s_bot;
double r = r_top/r_bot;
if ((r < 0) || ( r > 1) || (s < 0) || (s > 1))
//no intersection
return Math.Min(DistancePointLine(A,C,D),
Math.Min(DistancePointLine(B,C,D),
Math.Min(DistancePointLine(C,A,B),
DistancePointLine(D,A,B) ) ) );
return 0.0; //intersection exists
}
/// <summary>
/// Computes the distance from a point p to a line segment AB.
/// Note: NON-ROBUST!
/// </summary>
/// <param name="p">The point to compute the distance for.</param>
/// <param name="A">One point of the line.</param>
/// <param name="B">Another point of the line (must be different to A).</param>
/// <returns> The distance from p to line segment AB.</returns>
public static double DistancePointLine(Coordinate p, Coordinate A, Coordinate B)
{
// if start == end, then use pt distance
if (A.Equals(B))
return p.Distance(A);
// otherwise use comp.graphics.algorithms Frequently Asked Questions method
/*(1) AC dot AB
r = ---------
||AB||^2
r has the following meaning:
r=0 Point = A
r=1 Point = B
r<0 Point is on the backward extension of AB
r>1 Point is on the forward extension of AB
0<r<1 Point is interior to AB
*/
double r = ( (p.X - A.X) * (B.X - A.X) + (p.Y - A.Y) * (B.Y - A.Y) )
/
( (B.X - A.X) * (B.X - A.X) + (B.Y - A.Y) * (B.Y - A.Y) );
if (r <= 0.0) return p.Distance(A);
if (r >= 1.0) return p.Distance(B);
/*(2)
(Ay-Cy)(Bx-Ax)-(Ax-Cx)(By-Ay)
s = -----------------------------
Curve^2
Then the distance from C to Point = |s|*Curve.
*/
double s = ( (A.Y - p.Y) * (B.X - A.X) - (A.X - p.X) * (B.Y - A.Y) )
/
( (B.X - A.X) * (B.X - A.X) + (B.Y - A.Y) * (B.Y - A.Y) );
return Math.Abs(s) * Math.Sqrt(((B.X - A.X) * (B.X - A.X) + (B.Y - A.Y) * (B.Y - A.Y)));
}
/// <summary>
///
/// </summary>
/// <param name="p1"></param>
/// <param name="p2"></param>
/// <param name="q1"></param>
/// <param name="q2"></param>
/// <returns></returns>
private IntersectionTypes ComputeCollinearIntersection(Coordinate p1, Coordinate p2, Coordinate q1, Coordinate q2)
{
bool p1q1p2 = Envelope.Intersects(p1, p2, q1);
bool p1q2p2 = Envelope.Intersects(p1, p2, q2);
bool q1p1q2 = Envelope.Intersects(q1, q2, p1);
bool q1p2q2 = Envelope.Intersects(q1, q2, p2);
if(p1q1p2 && p1q2p2)
{
IntersectionPoints[0] = q1;
IntersectionPoints[1] = q2;
return IntersectionTypes.Collinear;
}
if(q1p1q2 && q1p2q2)
{
IntersectionPoints[0] = p1;
IntersectionPoints[1] = p2;
return IntersectionTypes.Collinear;
}
if(p1q1p2 && q1p1q2)
{
IntersectionPoints[0] = q1;
IntersectionPoints[1] = p1;
return q1.Equals(p1) && !p1q2p2 && !q1p2q2 ? IntersectionTypes.PointIntersection : IntersectionTypes.Collinear;
}
if(p1q1p2 && q1p2q2)
{
IntersectionPoints[0] = q1;
IntersectionPoints[1] = p2;
return q1.Equals(p2) && !p1q2p2 && !q1p1q2 ? IntersectionTypes.PointIntersection : IntersectionTypes.Collinear;
}
if(p1q2p2 && q1p1q2)
{
IntersectionPoints[0] = q2;
IntersectionPoints[1] = p1;
return q2.Equals(p1) && !p1q1p2 && !q1p2q2 ? IntersectionTypes.PointIntersection : IntersectionTypes.Collinear;
}
if(p1q2p2 && q1p2q2)
{
IntersectionPoints[0] = q2;
IntersectionPoints[1] = p2;
return q2.Equals(p2) && !p1q1p2 && !q1p1q2 ? IntersectionTypes.PointIntersection : IntersectionTypes.Collinear;
}
return IntersectionTypes.NoIntersection;
}
/// <summary>
///
/// </summary>
/// <param name="pt"></param>
private void AddPt(Coordinate pt)
{
Coordinate bufPt = new Coordinate(pt);
_precisionModel.MakePrecise(bufPt);
// don't add duplicate points
Coordinate lastPt = null;
if (_ptList.Count >= 1)
lastPt = _ptList.Last();
if (lastPt != null && bufPt.Equals(lastPt)) return;
_ptList.Add(bufPt);
}
/// <summary>
///
/// </summary>
private void ClosePts()
{
if (_ptList.Count < 1) return;
Coordinate startPt = new Coordinate(_ptList[0]);
Coordinate lastPt = _ptList[_ptList.Count - 1];
if (startPt.Equals(lastPt)) return;
_ptList.Add(startPt);
}
/// <summary>
///
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <param name="tolerance"></param>
/// <returns></returns>
protected virtual bool Equal(Coordinate a, Coordinate b, double tolerance)
{
if (tolerance == 0)
return a.Equals(b);
return a.Distance(b) <= tolerance;
}
/// <summary>
///
/// </summary>
/// <param name="p"></param>
/// <param name="l"></param>
/// <returns></returns>
private static Location Locate(Coordinate p, ILineString l)
{
// bounding-box check
if (!l.EnvelopeInternal.Intersects(p))
return Location.Exterior;
Coordinate[] pt = l.Coordinates;
if(!l.IsClosed)
if(p.Equals(pt[0]) || p.Equals(pt[pt.Length - 1]))
return Location.Boundary;
if (CGAlgorithms.IsOnLine(p, pt))
return Location.Interior;
return Location.Exterior;
}
/// <summary>
/// Computes the distance from a line segment AB to a line segment CD.
/// Note: NON-ROBUST!
/// </summary>
/// <param name="A">A point of one line.</param>
/// <param name="B">The second point of the line (must be different to A).</param>
/// <param name="C">One point of the line.</param>
/// <param name="D">Another point of the line (must be different to A).</param>
/// <returns>The distance from line segment AB to line segment CD.</returns>
public static double DistanceLineLine(Coordinate A, Coordinate B, Coordinate C, Coordinate D)
{
// check for zero-length segments
if (A.Equals(B))
return DistancePointLine(A,C,D);
if (C.Equals(D))
return DistancePointLine(D,A,B);
// AB and CD are line segments
/* from comp.graphics.algo
*
* Solving the above for r and s yields
*
* (Ay-Cy)(Dx-Cx)-(Ax-Cx)(Dy-Cy)
* r = ----------------------------- (eqn 1)
* (Bx-Ax)(Dy-Cy)-(By-Ay)(Dx-Cx)
*
* (Ay-Cy)(Bx-Ax)-(Ax-Cx)(By-Ay)
* s = ----------------------------- (eqn 2)
* (Bx-Ax)(Dy-Cy)-(By-Ay)(Dx-Cx)
*
* Let P be the position vector of the
* intersection point, then
* P=A+r(B-A) or
* Px=Ax+r(Bx-Ax)
* Py=Ay+r(By-Ay)
* By examining the values of r & s, you can also determine some other limiting
* conditions:
* If 0<=r<=1 & 0<=s<=1, intersection exists
* r<0 or r>1 or s<0 or s>1 line segments do not intersect
* If the denominator in eqn 1 is zero, AB & CD are parallel
* If the numerator in eqn 1 is also zero, AB & CD are collinear.
*/
var noIntersection = false;
if (!Envelope.Intersects(A, B, C, D))
{
noIntersection = true;
}
else
{
var denom = (B.X - A.X) * (D.Y - C.Y) - (B.Y - A.Y) * (D.X - C.X);
if (denom == 0)
{
noIntersection = true;
}
else
{
var r_num = (A.Y - C.Y) * (D.X - C.X) - (A.X - C.X) * (D.Y - C.Y);
var s_num = (A.Y - C.Y) * (B.X - A.X) - (A.X - C.X) * (B.Y - A.Y);
var s = s_num / denom;
var r = r_num / denom;
if ((r < 0) || (r > 1) || (s < 0) || (s > 1))
{
noIntersection = true;
}
}
}
if (noIntersection)
{
return MathUtil.Min(
DistancePointLine(A, C, D),
DistancePointLine(B, C, D),
DistancePointLine(C, A, B),
DistancePointLine(D, A, B));
}
// segments intersect
return 0.0;
}
/// <summary>
/// Tests whether the segment p0-p1 intersects the hot pixel tolerance square.
/// Because the tolerance square point set is partially open (along the
/// top and right) the test needs to be more sophisticated than
/// simply checking for any intersection.
/// However, it can take advantage of the fact that the hot pixel edges
/// do not lie on the coordinate grid.
/// It is sufficient to check if any of the following occur:
/// - a proper intersection between the segment and any hot pixel edge.
/// - an intersection between the segment and BOTH the left and bottom hot pixel edges
/// (which detects the case where the segment intersects the bottom left hot pixel corner).
/// - an intersection between a segment endpoint and the hot pixel coordinate.
/// </summary>
/// <param name="p0"></param>
/// <param name="p1"></param>
/// <returns></returns>
private bool IntersectsToleranceSquare(Coordinate p0, Coordinate p1)
{
var intersectsLeft = false;
var intersectsBottom = false;
//Console.WriteLine("Hot Pixel: " + WKTWriter.ToLineString(corner));
//Console.WriteLine("Line: " + WKTWriter.ToLineString(p0, p1));
_li.ComputeIntersection(p0, p1, _corner[0], _corner[1]);
if (_li.IsProper) return true;
_li.ComputeIntersection(p0, p1, _corner[1], _corner[2]);
if (_li.IsProper) return true;
if (_li.HasIntersection) intersectsLeft = true;
_li.ComputeIntersection(p0, p1, _corner[2], _corner[3]);
if (_li.IsProper) return true;
if (_li.HasIntersection) intersectsBottom = true;
_li.ComputeIntersection(p0, p1, _corner[3], _corner[0]);
if (_li.IsProper) return true;
if (intersectsLeft && intersectsBottom) return true;
if (p0.Equals(_pt)) return true;
if (p1.Equals(_pt)) return true;
return false;
}
/// <summary>
/// Compute the projection of a point onto the line determined
/// by this line segment.
/// Notice that the projected point
/// may lie outside the line segment. If this is the case,
/// the projection factor will lie outside the range [0.0, 1.0].
/// </summary>
/// <param name="p"></param>
/// <returns></returns>
public virtual Coordinate Project(Coordinate p)
{
if (p.Equals(P0) || p.Equals(P1))
return new Coordinate(p);
double r = ProjectionFactor(p);
Coordinate coord = new Coordinate();
coord.X = P0.X + r * (P1.X - P0.X);
coord.Y = P0.Y + r * (P1.Y - P0.Y);
return coord;
}
private void Move(Coordinate currentCoordinate, Coordinate target, int step)
{
//reached target
if (currentCoordinate.Equals(target))
{
//_pathFound = true;
return;
}
//try up
if(IsCellInsideLabyrinth(currentCoordinate.X, currentCoordinate.Y - 1) && CanMoveTo(currentCoordinate, MoveDirection.Up) && !HasBeenThere(new Coordinate(currentCoordinate.X, currentCoordinate.Y - 1)))
{
_tempLabirynth[currentCoordinate.X, currentCoordinate.Y - 1] = step;
//Move(new Coordinate(currentCoordinate.X, currentCoordinate.Y - 1), target, step + 1);
}
//try down
if (IsCellInsideLabyrinth(currentCoordinate.X, currentCoordinate.Y + 1) && CanMoveTo(currentCoordinate, MoveDirection.Down) && !HasBeenThere(new Coordinate(currentCoordinate.X, currentCoordinate.Y + 1)))
{
_tempLabirynth[currentCoordinate.X, currentCoordinate.Y + 1] = step;
//Move(new Coordinate(currentCoordinate.X, currentCoordinate.Y + 1), target, step + 1);
}
//try left
if(IsCellInsideLabyrinth(currentCoordinate.X - 1, currentCoordinate.Y) && CanMoveTo(currentCoordinate, MoveDirection.Left) && !HasBeenThere(new Coordinate(currentCoordinate.X - 1, currentCoordinate.Y)))
{
_tempLabirynth[currentCoordinate.X - 1, currentCoordinate.Y] = step;
//Move(new Coordinate(currentCoordinate.X - 1, currentCoordinate.Y), target, step + 1);
}
//try right
if (IsCellInsideLabyrinth(currentCoordinate.X + 1, currentCoordinate.Y) && CanMoveTo(currentCoordinate, MoveDirection.Right) && !HasBeenThere(new Coordinate(currentCoordinate.X + 1, currentCoordinate.Y)))
{
_tempLabirynth[currentCoordinate.X + 1, currentCoordinate.Y] = step;
//Move(new Coordinate(currentCoordinate.X + 1, currentCoordinate.Y), target, step + 1);
}
}
/// <summary>
/// Compute the projection of a point onto the line determined
/// by this line segment.
/// Note that the projected point may lie outside the line segment.
/// If this is the case, the projection factor will lie outside the range [0.0, 1.0].
/// </summary>
/// <param name="p"></param>
/// <returns></returns>
public Coordinate Project(Coordinate p)
{
if (p.Equals(_p0) || p.Equals(_p1))
return new Coordinate(p);
var r = ProjectionFactor(p);
var coord = new Coordinate { X = _p0.X + r * (_p1.X - _p0.X), Y = _p0.Y + r * (_p1.Y - _p0.Y) };
return coord;
}
public void SameCoordinateEquals()
{
//arrange
Coordinate first = new Coordinate(1, 1);
Coordinate second = new Coordinate(1, 1);
bool expected = true;
//act
bool actual = first.Equals(second);
//assert
Assert.AreEqual(expected, actual);
}
