/// <summary>
/// Returns the collisionvector of a corner collision calculated with a circle in the center of the collision box.
/// </summary>
/// <param name="obj1">The object colliding with the corner.</param>
/// <param name="corner">The circle for this corner.</param>
/// <returns>A Vector2 of the collision.</returns>
public static Vector2 DiagonalCollision(CollisionObject obj1, Circle corner)
{
#region variables from obj1
Vector2 speed = obj1.GetSpeedTotal();
Vector2 startPos = obj1.GetCenter();
#endregion
#region Get line from movement vector and position
Line trajectoryObj = new Line(startPos, startPos + speed);
#endregion
#region Find where line intersects circle
Vector2[] intersects = corner.Intersects(trajectoryObj);
#endregion
#region Find which one of the intersections is closer
int closestIndex = GetClosestVector(intersects, startPos);
if (closestIndex == -1)
{
return(Vector2.Zero);
}
Vector2 closest = intersects[closestIndex];
#endregion
#region Define startpoint of vector
Vector2 startPoint = closest - speed;
#endregion
#region Construct a line through the intersection found earlier and the center of the circle
Line middlePointThroughIntersect = new Line(closest, corner.center);
#endregion
#region Construct a line perpandicular to this line through the startpoint
Line PerpendicularLineThroughStart = new Line(new Vector2(middlePointThroughIntersect.twoPointFormY, -middlePointThroughIntersect.twoPointFormX), startPoint);
#endregion
#region Find the intersection of the perpandicular with the line through the center of the circle
Vector2 intersectPerp = PerpendicularLineThroughStart.Intersects(middlePointThroughIntersect);
#endregion
#region Find vector from startposition to intersect of perpandicular and center line
Vector2 diffStartIntersect = intersectPerp - startPoint;
#endregion
#region Add vector to the intersection to find the reflected point
Vector2 endPoint = intersectPerp + diffStartIntersect;
#endregion
#region Return vector from intersect of incoming vector's intersect with circle to reflected point
return(-(endPoint - closest) - speed);
#endregion
//Illustration in documentation
}
