protected virtual void OnTransformDetected(SKTransformDetectedEventArgs e) => TransformDetected?.Invoke(this, e);
private bool OnTouchMoved(SKTouchEventArgs e)
{
var ticks = DateTime.Now.Ticks;
var location = e.Location;
touches[e.Id] = new TouchEvent(e.Id, location, ticks, e.InContact);
// update the fling tracker
if (e.InContact)
{
flingTracker.AddEvent(e.Id, location, ticks);
}
// if this is a mouse or pen hover, then raise an event
if (!e.InContact)
{
var args = new SKHoverDetectedEventArgs(e.Location);
OnHoverDetected(args);
return(args.Handled);
}
var touchPoints = GetInContactTouchPoints();
// TODO: potentially handle move events before gestures
switch (touchMode)
{
case TouchMode.Single:
{
if (touchPoints.Length != 1)
{
return(false);
}
var touchPosition = touchPoints.First();
if (!previousValues.Center.IsEmpty)
{
var args = new SKTransformDetectedEventArgs(touchPosition, previousValues.Center);
OnTransformDetected(args);
}
previousValues.Center = touchPosition;
}
break;
case TouchMode.Multiple:
{
if (touchPoints.Length != 2)
{
return(false);
}
var prevVals = previousValues;
var pinchValue = PinchValue.FromLocations(touchPoints);
var rotationDelta = pinchValue.Angle - prevVals.Angle;
rotationDelta %= 360;
if (rotationDelta > 180)
{
rotationDelta -= 360;
}
else if (rotationDelta < -180)
{
rotationDelta += 360;
}
var args = new SKTransformDetectedEventArgs(pinchValue.Center, prevVals.Center, pinchValue.Radius / prevVals.Radius, rotationDelta);
OnTransformDetected(args);
previousValues = pinchValue;
}
break;
}
return(true);
}
