internal Trace(CursorPoint cursor, Group group, List<IGestureListener> targets, bool guiTargets)
{
m_id = s_idCounter++;
m_group = group;
m_path = new List<CursorPoint>();
m_path.Add(cursor);
m_first = m_last = cursor;
m_state = States.ADDED;
m_isAlive = true;
m_initialTargets = new List<IGestureListener>();
m_finalTargets = new List<IGestureListener>();
m_enteringTargets = new List<IGestureListener>();
m_currentTargets = new List<IGestureListener>();
m_leavingTargets = new List<IGestureListener>();
m_intersectionTargets = new List<IGestureListener>();
m_unionTargets = new List<IGestureListener>();
m_group.StartTrace(this);
UpdateTargets(targets, guiTargets);
}
public float SquareDistance(CursorPoint cursor)
{
float dx = m_x - cursor.X;
float dy = m_y - cursor.Y;
return dx * dx + dy * dy;
}
private bool TryResurrectTrace(CursorPoint cursor, out Trace resurrectingTrace)
{
resurrectingTrace = null;
float minDist = Settings.TRACE_SPACE_GAP * Settings.TRACE_SPACE_GAP;
float dist;
foreach (Trace trace in m_resurrectableTraces)
{
dist = trace.Last.SquareDistance(cursor);
if (dist < minDist)
{
minDist = dist;
resurrectingTrace = trace;
}
}
if (resurrectingTrace != null)
{
m_resurrectableTraces.Remove(resurrectingTrace);
return true;
}
else
return false;
}
/// <summary>
/// Clustering method. Determine the best matching group to add the cursor's trace to.
/// If none existing groups are suitable, a new one is created.
/// </summary>
/// <param name="cursor">The cursor to cluster</param>
/// <param name="targets">The given cursor's targets</param>
/// <param name="guiTargets">Flag indicating whether the given targets are GUI controls</param>
/// <returns>The matching group where to add the given cursor-s trace.</returns>
private Group GetMatchingGroup(CursorPoint cursor, List<IGestureListener> targets, bool isZControl)
{
Group matchingGroup = null;
float minDist = Settings.GROUPING_SPACE * Settings.GROUPING_SPACE;
float tempDist;
foreach (Group group in m_activeGroups)
{
// filter out groups that don't accept the trace
if (!group.AcceptNewCursor(cursor, targets, isZControl))
continue;
// group all traces on the same zControl
if (isZControl && group.OnZControl && targets[0] == group.ClosestCurrentTarget)
{
matchingGroup = group;
break;
}
// find the closest
tempDist = group.SquareDistanceToNearestTrace(cursor, Settings.CLUSTERING_ONLY_WITH_ALIVE_TRACES);
if (tempDist < minDist)
{
minDist = tempDist;
matchingGroup = group;
}
}
// if no group is found, create a new one
if (matchingGroup == null)
matchingGroup = CreateGroup();
return matchingGroup;
}
protected void OnUp(CursorPoint c)
{
AppendEvent(Up, new BasicMultiFingerEventArgs("Up", Group.Id, c.X, c.Y, m_numberOfCurrentFingers, m_validInitialZTarget));
}
private void UpdateCursorValues(CursorPoint cursor)
{
if (m_state != States.REMOVED)
{
double dt = (double)(cursor.TimeStamp - m_last.TimeStamp) / 1000;
double xSpeed = ((double)cursor.X - (double)m_last.X) / dt;
double ySpeed = ((double)cursor.Y - (double)m_last.Y) / dt;
double motionSpeed = Math.Sqrt(xSpeed * xSpeed + ySpeed * ySpeed);
double motionAccel = (motionSpeed - (double)m_last.MotionSpeed) / dt;
cursor.XSpeed = (float)xSpeed;
cursor.YSpeed = (float)ySpeed;
cursor.MotionSpeed = (float)motionSpeed;
cursor.MotionAcceleration = (float)motionAccel;
}
//Console.WriteLine("x_sp={0},\ty_sp={1},\tsp={2},\tac={3}", cursor.XSpeed, cursor.YSpeed, cursor.MotionSpeed, cursor.MotionAcceleration);
}
internal void AppendRemovingCursor(
CursorPoint cursor, List<IGestureListener> targets, bool isZControl)
{
UpdateCursorValues(cursor);
m_path.Add(cursor);
m_last = cursor;
m_isAlive = false;
m_state = States.REMOVED;
m_group.EndTrace(this);
UpdateTargets(targets, isZControl);
}
internal void AppendAddingOrUpdatingCursor(
CursorPoint cursor, List<IGestureListener> targets, bool isZControl)
{
UpdateCursorValues(cursor);
m_path.Add(cursor);
m_last = cursor;
if (m_state == States.REMOVED)
{
m_state = States.RESET;
m_isAlive = true;
}
else
m_state = States.UPDATED;
m_group.UpdateTrace(this);
UpdateTargets(targets, isZControl);
}
