public void GridLineIntersects()
{
//
// TODO: Add test logic here
//
GridLine lineA = new GridLine(new GridVector2(-5, 0),
new GridVector2(-10, 0));
GridLine lineB = new GridLine(new GridVector2(0, 5),
new GridVector2(0, -5));
GridVector2 intersect = new GridVector2();
bool result = lineA.Intersects(lineB, out intersect);
Debug.Assert(result == true);
Debug.Assert(intersect.X == 0 && intersect.Y == 0);
}
public bool Intersects(GridLine seg, out GridVector2 Intersection)
{
//Function for each line
//Ax + By = C
Intersection = new GridVector2();
if (seg == null)
throw new ArgumentNullException("seg");
if (this.Direction == seg.Direction)
return false;
GridVector2 A = Origin;
GridVector2 B = Origin + Direction;
GridVector2 segA = seg.Origin;
GridVector2 segB = seg.Origin + seg.Direction;
double A1 = B.Y - A.Y;
double A2 = segB.Y - segA.Y;
double B1 = A.X - B.X;
double B2 = segA.X - segB.X;
double C1 = A1 * A.X + B1 * A.Y;
double C2 = A2 * segA.X + B2 * segA.Y;
double det = A1 * B2 - A2 * B1;
//Check if lines are parallel
if (det == 0)
{
return false;
}
else
{
double x = (B2 * C1 - B1 * C2) / det;
double y = (A1 * C2 - A2 * C1) / det;
Intersection = new GridVector2(x, y);
return true;
}
}
