/// <summary>
/// Ricochet coordinate calculation
/// </summary>
/// <param name="ballCoordinates">Ball Coordinates</param>
/// <returns>Ricochet Ball Coordinates</returns>
public BallCoordinates Ricochet(BallCoordinates ballCoordinates)
{
try
{
Coordinates2D intersectionPoint = FindNearestIntersectionPoint(ballCoordinates);
//Marks.DrawRicochetMark(Convert.ToInt32(intersectionPoint.X), Convert.ToInt32(intersectionPoint.Y), true);
DateTime ricocheTime = FindRicochetTime(ballCoordinates, intersectionPoint);
Vector2D vector = FindIntersectionVector(ballCoordinates.Vector, intersectionPoint);
BallCoordinates coordinates = new BallCoordinates(
Convert.ToInt32(intersectionPoint.X),
Convert.ToInt32(intersectionPoint.Y), ricocheTime);
coordinates.Vector = vector;
return(coordinates);
}
catch (Exception e)
{
throw new NotSupportedException(String.Format(
"[{0}] Failed to find ricochet coordinates. Reason: {1}",
MethodBase.GetCurrentMethod().Name, e.Message));
}
}
/// <summary>
/// Find intersection time based on ball coordinates, timestamp, vector and intersection point.
/// </summary>
/// <param name="ballCoordinates">Ball coordinates before intersection with border</param>
/// <param name="intersection">Intersection with border point</param>
/// <exception cref="ArgumentOutOfRangeException">Thrown in case calculated intersection time is too big</exception>
/// <exception cref="NotSupportedException">Thrown in case intersection coordinates undefined.</exception>
/// <returns>Intersection timestamp</returns>
public DateTime FindRicochetTime(BallCoordinates ballCoordinates, Coordinates2D intersection)
{
VerifyBallCoordinatesAndVectorInput(ballCoordinates);
if (intersection == null || !intersection.IsDefined)
{
throw new NotSupportedException(String.Format("[{0}] Intersection coordinates undefined!", MethodBase.GetCurrentMethod().Name));
}
double distance = ballCoordinates.Distance(intersection);
double velocity = ballCoordinates.Vector.Velocity();
double deltaT = distance / velocity;
return(ballCoordinates.Timestamp + TimeSpan.FromSeconds(deltaT));
}
/// <summary>
/// Calculate intersection vector from intersection point
/// </summary>
/// <param name="vector">Last known vector before intersection</param>
/// <param name="intersection">Intersection point with border</param>
/// <exception cref="NotSupportedException">Thrown in case passed intersection point is not on the border</exception>
/// <returns>Ball Vector after intersection</returns>
public Vector2D FindIntersectionVector(Vector2D vector, Coordinates2D intersection)
{
if (vector == null)
{
throw new NotSupportedException(String.Format(
"[{0}] Vector from Intersection point can not be found because last known vector is NULL",
MethodBase.GetCurrentMethod().Name));
}
if (!vector.IsDefined)
{
throw new NotSupportedException(String.Format(
"[{0}] Vector from Intersection point can not be found because last known vector is undefined",
MethodBase.GetCurrentMethod().Name));
}
if (!intersection.IsDefined)
{
throw new NotSupportedException(String.Format(
"[{0}] Vector from Intersection point can not be found because intersection point is undefined",
MethodBase.GetCurrentMethod().Name));
}
bool isDirectionChanged = false;
double x = vector.X * RicochetFactor;
double y = vector.Y * RicochetFactor;
if (intersection.Y == MinBorderY || intersection.Y == MaxBorderY)
{
y *= (-1);
isDirectionChanged = true;
}
if (intersection.X == MinBorderX || intersection.X == MaxBorderX)
{
x *= (-1);
isDirectionChanged = true;
}
if (!isDirectionChanged)
{
throw new NotSupportedException(
String.Format("[{0}] Intersection point must be on border! Current point is {1}x{2}",
MethodBase.GetCurrentMethod().Name, intersection.X, intersection.Y));
}
return(new Vector2D(x, y));
}
/// <summary>
/// Find nearest intersection point with table borders based on
/// - given ball coordinates and vector
/// </summary>
/// <param name="ballCoordinates">Defined coordinates with defined vector</param>
/// <returns>Coordinates of intersection with border</returns>
public Coordinates2D FindNearestIntersectionPoint(BallCoordinates ballCoordinates)
{
//verify we can proceed to calculate intersection
VerifyBallCoordinatesAndVectorInput(ballCoordinates);
Dictionary <Vector2D, Coordinates2D> borderIntersection = new Dictionary <Vector2D, Coordinates2D>();
List <Vector2D> vectors = new List <Vector2D>();
//get line slope
double m = CalculateLineSlope(ballCoordinates.Vector);
if (ballCoordinates.Vector.X != 0)
{
double yb = CalculateY2OnLine(m, ballCoordinates.X, ballCoordinates.Y, MinBorderX);
double yc = CalculateY2OnLine(m, ballCoordinates.X, ballCoordinates.Y, MaxBorderX);
Coordinates2D B = new Coordinates2D(MinBorderX, yb);
Vector2D vB = new Vector2D(B.X - ballCoordinates.X, B.Y - ballCoordinates.Y);
vectors.Add(vB);
borderIntersection.Add(vB, B); //B
Coordinates2D C = new Coordinates2D(MaxBorderX, yc);
Vector2D vC = new Vector2D(C.X - ballCoordinates.X, C.Y - ballCoordinates.Y);
vectors.Add(vC);
borderIntersection.Add(vC, C); //C
}
if (ballCoordinates.Vector.Y != 0)
{
double xa = CalculateX2OnLine(m, ballCoordinates.X, ballCoordinates.Y, MinBorderY);
double xd = CalculateX2OnLine(m, ballCoordinates.X, ballCoordinates.Y, MaxBorderY);
Coordinates2D A = new Coordinates2D(xa, MinBorderY);
Vector2D vA = new Vector2D(A.X - ballCoordinates.X, A.Y - ballCoordinates.Y);
vectors.Add(vA);
borderIntersection.Add(vA, A); //A
Coordinates2D D = new Coordinates2D(xd, MaxBorderY);
Vector2D vD = new Vector2D(D.X - ballCoordinates.X, D.Y - ballCoordinates.Y);
vectors.Add(vD);
borderIntersection.Add(vD, D); //D
}
//remove points from wrong direction
foreach (Vector2D vector in vectors)
{
double direction = vector.ScalarProduct(ballCoordinates.Vector)
/ (vector.Velocity() * ballCoordinates.Vector.Velocity());
if (Math.Round(direction, 0) != 1)
{
borderIntersection.Remove(vector);
}
}
//if no points found => Error, consider adding error rate threshold
if (borderIntersection.Count < 1)
{
Log.Print("No vectors found!", eCategory.Error, LogTag.VECTOR);
}
//get nearest point
Coordinates2D intersectionPoint = null;
double minDistance = MaxBorderX * MaxBorderY;
foreach (Coordinates2D intersection in borderIntersection.Values)
{
double dist = intersection.Distance(ballCoordinates);
if (dist < minDistance)
{
minDistance = dist;
intersectionPoint = intersection;
}
}
return(intersectionPoint);
}
/// <summary>
/// Coordinates scalar product
/// </summary>
/// <param name="coordA">Coordinate to calculate Scalar Product</param>
/// <param name="coordB">Coordinate to calculate Scalar Product With</param>
/// <returns>Scalar Product</returns>
public static double ScalarProduct(Coordinates2D coordA, Coordinates2D coordB)
{
return(coordA.X * coordB.X + coordA.Y * coordB.Y);
}