public static SKPoint?FindIntersection(SKLine a, SKPoint c0, SKPoint c1, SKPoint c2, SKPoint c3, bool segment)
{
return(FindIntersection(a, new SKLine(c0, c1), segment) ??
FindIntersection(a, new SKLine(c1, c2), segment) ??
FindIntersection(a, new SKLine(c2, c3), segment) ??
FindIntersection(a, new SKLine(c3, c0), segment));
}
public bool IntersectsWith(Quad value)
{
return(SKLine.FindIntersection(new SKLine(pointTopLeft, pointTopRight), value, true) != null ||
SKLine.FindIntersection(new SKLine(pointTopRight, pointBottomRight), value, true) != null ||
SKLine.FindIntersection(new SKLine(pointBottomRight, pointBottomLeft), value, true) != null ||
SKLine.FindIntersection(new SKLine(pointBottomLeft, pointTopLeft), value, true) != null);
}
public static SKPoint?FindIntersection(SKLine a, SKLine b, bool segment)
{
float x1 = a.a.X;
float y1 = a.a.Y;
float x2 = a.b.X;
float y2 = a.b.Y;
float x3 = b.a.X;
float y3 = b.a.Y;
float x4 = b.b.X;
float y4 = b.b.Y;
float denominator = (x1 - x2) * (y3 - y4) - (y1 - y2) * (x3 - x4);
if (denominator == 0)
{
return(null);
}
if (segment)
{
float t = ((x1 - x3) * (y3 - y4) - (y1 - y3) * (x3 - x4)) / denominator;
if (t < 0 || t > 1)
{
return(null);
}
float u = -((x1 - x2) * (y1 - y3) - (y1 - y2) * (x1 - x3)) / denominator;
if (u < 0 || u > 1)
{
return(null);
}
}
float xNominator = (x1 * y2 - y1 * x2) * (x3 - x4) - (x1 - x2) * (x3 * y4 - y3 * x4);
float yNominator = (x1 * y2 - y1 * x2) * (y3 - y4) - (y1 - y2) * (x3 * y4 - y3 * x4);
float px = xNominator / denominator;
float py = yNominator / denominator;
return(new SKPoint(px, py));
}
public static SKPoint?FindIntersection(SKLine a, Quad q, bool segment)
{
return(FindIntersection(a, q.TopLeft, q.TopRight, q.BottomRight, q.BottomLeft, segment));
}