private void Manipulate()
{
TouchManipulationInfo[] infos = new TouchManipulationInfo[touchDictionary.Count];
touchDictionary.Values.CopyTo(infos, 0);
SKMatrix touchMatrix = SKMatrix.CreateIdentity();
if (infos.Length == 1 && Type != BitmapType.Main)
{
SKPoint prevPoint = infos[0].PreviousPoint;
SKPoint newPoint = infos[0].NewPoint;
SKPoint pivotPoint = Matrix.MapPoint(Bitmap.Width / 2, Bitmap.Height / 2);
touchMatrix = TouchManager.OneFingerManipulate(prevPoint, newPoint, pivotPoint);
}
else if (infos.Length >= 2)
{
int pivotIndex = infos[0].NewPoint == infos[0].PreviousPoint ? 0 : 1;
SKPoint pivotPoint = infos[pivotIndex].NewPoint;
SKPoint newPoint = infos[1 - pivotIndex].NewPoint;
SKPoint prevPoint = infos[1 - pivotIndex].PreviousPoint;
touchMatrix = TouchManager.TwoFingerManipulate(prevPoint, newPoint, pivotPoint);
}
SKMatrix matrix = Matrix;
matrix.PostConcat(touchMatrix);
Matrix = matrix;
}
internal void ProcessTouchEvent(long id, TouchActionType type, SKPoint location)
{
switch (type)
{
case TouchActionType.Pressed:
touchDictionary.Add(id, new TouchManipulationInfo
{
PreviousPoint = location,
NewPoint = location
});
break;
case TouchActionType.Moved:
TouchManipulationInfo info = touchDictionary[id];
info.NewPoint = location;
Manipulate();
info.PreviousPoint = info.NewPoint;
break;
case TouchActionType.Released:
touchDictionary[id].NewPoint = location;
Manipulate();
touchDictionary.Remove(id);
break;
case TouchActionType.Cancelled:
touchDictionary.Remove(id);
break;
}
}