/// <summary>
/// Calculate the intersection point between the segment and line.
/// </summary>
/// <param name="sEq">The segment equation.</param>
/// <param name="lEq">The line equation.</param>
/// <returns>Returns the intersection point.</returns>
public static Point GetIntersection(SegmentEquation sEq, LinearEquation lEq)
{
var pt = LinearEquation.GetIntersection(sEq, lEq);
if (sEq.IsPointInRange(pt))
{
return(pt);
}
return(null);
}
/// <summary>
/// Calculate the intersection point between the 2 segments.
/// </summary>
/// <param name="eq1">The first segment equation.</param>
/// <param name="eq2">The second segment equation.</param>
/// <returns>Returns the intersection point.</returns>
public static Point GetIntersection(SegmentEquation eq1, SegmentEquation eq2)
{
var pt = LinearEquation.GetIntersection(eq1, eq2);
if (eq1.IsPointInRange(pt) && eq2.IsPointInRange(pt))
{
return(pt);
}
return(null);
}
/// <summary>
/// Calculate the intersection points when a line across many segments (Special).
/// </summary>
/// <param name="sEqs">The segment equations.</param>
/// <param name="lEq">The line equation.</param>
/// <returns>Returns the intersection points.</returns>
public static List <Point> GetIntersectionSp(IEnumerable <SegmentEquation> sEqs, LinearEquation lEq)
{
var pts = new List <Point>();
foreach (var sEq in sEqs)
{
var pt = SegmentEquation.GetIntersectionSp(sEq, lEq);
if (null != pt && sEq.IsPointInRange(pt))
{
pts.Add(pt);
}
}
return(pts);
}
/// <summary>
/// Calculate the intersection point between the segment and line (Special).
/// </summary>
/// <param name="sEq">The segment equation.</param>
/// <param name="lEq">The line equation.</param>
/// <returns>Returns the intersection points.</returns>
public static Point GetIntersectionSp(SegmentEquation sEq, LinearEquation lEq)
{
var pt = SegmentEquation.GetIntersection(sEq, lEq);
if (pt == sEq.endpoint1)
{
if (pt.Y <= sEq.endpoint2.Y)
{
pt = null;
}
}
else if (pt == sEq.endpoint2)
{
if (pt.Y <= sEq.endpoint1.Y)
{
pt = null;
}
}
return(pt);
}
/// <summary>
/// Judge wether the specified point lies within the interior or on the boundary of the specified polygon.
/// </summary>
/// <param name="pt">The specified point.</param>
/// <returns>Return true if the specified point intersects the polygon, otherwise false.</returns>
public bool IsIntersects(Point pt)
{
var line = new LinearEquation(pt, LinearType.ParallelXAxis);
var pts = SegmentEquation.GetIntersectionSp(this.sides, line);
int counter = 0;
foreach (var point in pts)
{
if (point == pt)
{
return(true);
}
else
{
if (point.X < pt.X)
{
counter++;
}
}
}
return(counter % 2 == 1);
}
/// <summary>
/// Calculate the intersection point between the segment and line (Special).
/// </summary>
/// <param name="sEq">The segment equation.</param>
/// <param name="lEq">The line equation.</param>
/// <returns>Returns the intersection points.</returns>
public static Point GetIntersectionSp(SegmentEquation sEq, LinearEquation lEq)
{
var pt = SegmentEquation.GetIntersection(sEq, lEq);
if (pt == sEq.endpoint1)
{
if (pt.Y <= sEq.endpoint2.Y)
{
pt = null;
}
}
else if (pt == sEq.endpoint2)
{
if (pt.Y <= sEq.endpoint1.Y)
{
pt = null;
}
}
return pt;
}
/// <summary>
/// Calculate the intersection point between the segment and line.
/// </summary>
/// <param name="sEq">The segment equation.</param>
/// <param name="lEq">The line equation.</param>
/// <returns>Returns the intersection point.</returns>
public static Point GetIntersection(SegmentEquation sEq, LinearEquation lEq)
{
var pt = LinearEquation.GetIntersection(sEq, lEq);
if (sEq.IsPointInRange(pt))
{
return pt;
}
return null;
}
/// <summary>
/// Calculate the intersection point between the 2 segments.
/// </summary>
/// <param name="eq1">The first segment equation.</param>
/// <param name="eq2">The second segment equation.</param>
/// <returns>Returns the intersection point.</returns>
public static Point GetIntersection(SegmentEquation eq1, SegmentEquation eq2)
{
var pt = LinearEquation.GetIntersection(eq1, eq2);
if (eq1.IsPointInRange(pt) && eq2.IsPointInRange(pt))
{
return pt;
}
return null;
}
/// <summary>
/// Get the length of the line.
/// </summary>
/// <param name="propName">The property name indicates the line.</param>
/// <param name="entity">An entity in the service.</param>
/// <returns>Return the length of the line.</returns>
private double GetLength(string propName, JObject entity)
{
var propVal = entity[propName]["coordinates"] as JArray;
var pts = new List<Point>();
for (int i = 0; i < propVal.Count - 1; i += 2)
{
var pt = new Point(Convert.ToDouble(propVal[i]), Convert.ToDouble(propVal[i + 1]));
pts.Add(pt);
}
var segs = new List<SegmentEquation>();
for (int i = 0; i < pts.Count - 1; i++)
{
var seg = new SegmentEquation(pts[i], pts[i + 1]);
segs.Add(seg);
}
double len = 0.0;
foreach (var seg in segs)
{
len += seg.Length;
}
return len;
}
