public static float MinimumDistance(Segment2D segment, Vector2f point)
{
Vector2f minimumDistancePoint;
return(Segment2D.MinimumDistance(segment, point, out minimumDistancePoint));
}
public static bool Intersects(Segment2D segment1, Segment2D segment2, out Vector2f intersectionPoint)
{
/* const float Epsilon = 0.00001f;
*
* Vector2 cmp = new Vector2(segment2.Start.X - segment1.Start.X, segment2.Start.Y - segment1.Start.Y);
* Vector2 rectangle = new Vector2(segment1.End.X - segment1.Start.X, segment1.End.Y - segment1.Start.Y);
* Vector2 s = new Vector2(segment2.End.X - segment2.Start.X, segment2.End.Y - segment2.Start.Y);
*
* float cmPxR = cmp.X * rectangle.Y - cmp.Y * rectangle.X;
* float cmPxS = cmp.X * s.Y - cmp.Y * s.X;
* float RxS = rectangle.X * s.Y - rectangle.Y * s.X;
*
* if (Math.Abs(cmPxR) < Epsilon)
* {
* intersectionPoint = Vector2.Zero;
* return true;
* }
*
* if (Math.Abs(RxS) < Epsilon)
* {
* intersectionPoint = default(Vector2);
* return false;
* }
*
* float rXsR = 1f / RxS;
* float t = cmPxS * rXsR;
* float u = cmPxR * rXsR;
*
* if (t >= 0f && t <= 1f && u >= 0f && u <= 1f)
* {
* intersectionPoint = segment1.Start + rectangle * t;
* return true;
* }
*
* intersectionPoint = default(Vector2);
* return false; */
const float Epsilon = 0.00001f;
float ua = (segment2.End.X - segment2.Start.X) * (segment1.Start.Y - segment2.Start.Y) - (segment2.End.Y - segment2.Start.Y) * (segment1.Start.X - segment2.Start.X);
float ub = (segment1.End.X - segment1.Start.X) * (segment1.Start.Y - segment2.Start.Y) - (segment1.End.Y - segment1.Start.Y) * (segment1.Start.X - segment2.Start.X);
float denominator = (segment2.End.Y - segment2.Start.Y) * (segment1.End.X - segment1.Start.X) - (segment2.End.X - segment2.Start.X) * (segment1.End.Y - segment1.Start.Y);
if (Math.Abs(denominator) <= Epsilon)
{
if (Math.Abs(ua) <= Epsilon && Math.Abs(ub) <= Epsilon)
{
intersectionPoint = (segment1.Start + segment1.End + segment2.Start + segment2.End) / 4f;
return(true);
}
}
else
{
ua /= denominator;
ub /= denominator;
if (ua >= 0 && ua <= 1 && ub >= 0 && ub <= 1)
{
intersectionPoint = new Vector2f
{
X = segment1.Start.X + ua * (segment1.End.X - segment1.Start.X),
Y = segment1.Start.Y + ua * (segment1.End.Y - segment1.Start.Y)
};
return(true);
}
}
intersectionPoint = default(Vector2);
return(false);
}
public Segment2D(Vector2f start, Vector2f end)
{
this.Start = start;
this.End = end;
}
public static bool Intersects(Vector2f p1, Vector2f p2, Vector2f p3, Vector2f p4, out Vector2f intersectionPoint)
{
return(Segment2D.Intersects(new Segment2D(p1, p2), new Segment2D(p3, p4), out intersectionPoint));
}
public Segment2D(float startX, float startY, float endX, float endY)
{
this.Start = new Vector2(startX, startY);
this.End = new Vector2(endX, endY);
}
