void Manipulate() { TouchManipulationInfo[] infos = new TouchManipulationInfo[touchDictionary.Count]; touchDictionary.Values.CopyTo(infos, 0); SKMatrix touchMatrix = SKMatrix.MakeIdentity(); if (infos.Length == 1) { 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; SKMatrix.PostConcat(ref matrix, touchMatrix); Matrix = matrix; }
public void ProcessTouchEvent(long id, TouchActionType type, SKPoint location) { switch (type) { case TouchActionType.Pressed: touchDictionary.Add(id, new TouchManipulationInfo { PreviousPoint = location, NewPoint = location }); //var scaleMatrix = SKMatrix.MakeScale(1.5f, 1.5f); //SKMatrix matrix = Matrix; //SKMatrix.PostConcat(ref matrix, scaleMatrix); //Matrix = matrix; 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; } }