//this method when we touch or drag the finger on the screen while scratching..
private void TouchEffect_TouchAction(object sender, TouchTracking.TouchActionEventArgs args)
{
switch (args.Type)
{
case TouchActionType.Pressed:
if (!inProgressPaths.ContainsKey(args.Id))
{
SKPath path = new SKPath();
path.MoveTo(ConvertToPixel(args.Location));
inProgressPaths.Add(args.Id, path);
canvasView.InvalidateSurface();
}
break;
case TouchActionType.Moved:
if (inProgressPaths.ContainsKey(args.Id))
{
SKPath path = inProgressPaths[args.Id];
path.LineTo(ConvertToPixel(args.Location));
canvasView.InvalidateSurface();
}
break;
case TouchActionType.Released:
if (inProgressPaths.ContainsKey(args.Id))
{
completedPaths.Add(inProgressPaths[args.Id]);
inProgressPaths.Remove(args.Id);
canvasView.InvalidateSurface();
}
break;
case TouchActionType.Cancelled:
if (inProgressPaths.ContainsKey(args.Id))
{
inProgressPaths.Remove(args.Id);
canvasView.InvalidateSurface();
}
break;
}
}
public void OnTouchAction(Element element, TouchActionEventArgs args)
{
TouchAction?.Invoke(element, args);
}
private void OnTouchEffectAction(object sender, TouchTracking.TouchActionEventArgs args)
{
Point pt = args.Location;
SKPoint point =
new SKPoint((float)(canvasView.CanvasSize.Width * pt.X / canvasView.Width),
(float)(canvasView.CanvasSize.Height * pt.Y / canvasView.Height));
switch (args.Type)
{
case TouchActionType.Pressed:
if (!touchDictionary.ContainsKey(args.Id))
{
touchDictionary.Add(args.Id, point);
}
//SetPixelsValue(args, view);
break;
case TouchActionType.Moved:
if (touchDictionary.ContainsKey(args.Id))
{
this.quickViewUpdateMode = true;
if (renderingMode == RenderingMode.DoubleBuffering)
{
Device.StartTimer(TimeSpan.FromMilliseconds(300), () => {
// MainThread.BeginInvokeOnMainThread(() =>
// {
Draw();
// });
return(this.quickViewUpdateMode);
});
}
if (touchDictionary.Count == 1)
{
long[] keys = new long[touchDictionary.Count];
touchDictionary.Keys.CopyTo(keys, 0);
// Find index of non-moving (pivot) finger
int pivotIndex = (keys[0] == args.Id) ? 1 : 0;
// Get the three points involved in the transform
// SKPoint pivotPoint = touchDictionary[keys[pivotIndex]];
SKPoint prevPoint = touchDictionary[args.Id];
SKPoint newPoint = point;
SKPoint delta = newPoint - prevPoint; // new_p = newPoint; old_p = prevPoint;
SKMatrix.PostConcat(ref matrix, SKMatrix.MakeTranslation(delta.X, delta.Y));
SKMatrix.PostConcat(ref bitmapMatrix, SKMatrix.MakeTranslation(delta.X, delta.Y));
touchDictionary[args.Id] = point;
}
else if (touchDictionary.Count >= 2)
{
// Copy two dictionary keys into array
long[] keys = new long[touchDictionary.Count];
touchDictionary.Keys.CopyTo(keys, 0);
int pivotIndex = (keys[0] == args.Id) ? 1 : 0;
SKPoint pivotPoint = touchDictionary[keys[pivotIndex]];
SKPoint prevPoint = touchDictionary[args.Id];
SKPoint newPoint = point;
double distance = Math.Sqrt(Math.Pow(Math.Abs(pivotPoint.X - newPoint.X), 2) + Math.Pow(Math.Abs(pivotPoint.Y - newPoint.Y), 2));
double oldDistance = Math.Sqrt(Math.Pow(Math.Abs(pivotPoint.X - prevPoint.X), 2) + Math.Pow(Math.Abs(pivotPoint.Y - prevPoint.Y), 2));
double differentDistance = distance / oldDistance;
SKPoint centerPoint = new SKPoint()
{
X = (newPoint.X + pivotPoint.X) / 2,
Y = (newPoint.Y + pivotPoint.Y) / 2
};
SKPoint oldCenterPoint = new SKPoint()
{
X = (prevPoint.X + pivotPoint.X) / 2,
Y = (prevPoint.Y + pivotPoint.Y) / 2
};
SKMatrix translationMatrix = SKMatrix.CreateTranslation((centerPoint.X - oldCenterPoint.X) /*/matrix.ScaleX*/, (centerPoint.Y - oldCenterPoint.Y) /*/ matrix.ScaleX*/);
SKMatrix scaleMatrix = SKMatrix.Identity;
if (!(matrix.ScaleX > 8 && differentDistance > 1))
{
scaleMatrix = SKMatrix.CreateScale((float)differentDistance, (float)differentDistance, centerPoint.X, centerPoint.Y /* pivotPoint.X, pivotPoint.Y*/);
}
SKMatrix.PostConcat(ref matrix, scaleMatrix); // NEW "PostContact() DOES NOT WORKING CORRECTLY!!!"
SKMatrix.PostConcat(ref matrix, translationMatrix);
SKMatrix.PostConcat(ref bitmapMatrix, scaleMatrix); // NEW "PostContact() DOES NOT WORKING CORRECTLY!!!"
SKMatrix.PostConcat(ref bitmapMatrix, translationMatrix);
touchDictionary[args.Id] = point;
}
}
break;
case TouchActionType.Released:
case TouchActionType.Cancelled:
if (touchDictionary.ContainsKey(args.Id))
{
touchDictionary.Remove(args.Id);
}
if (matrix.ScaleX < 0.2)
{
matrix = SKMatrix.MakeIdentity();
}
//resetScale();
this.quickViewUpdateMode = false;
updateBitmap();
break;
}
this.canvasView.InvalidateSurface();
}
private void OnTouch
(object sender, TouchTracking.TouchActionEventArgs args)
{
// Convert touch point to pixel point
_touch.Current = SkiaSharpHelper.ToPixel(args.Location.X, args.Location.Y, ref thumbsCanvas);
// Check bounds
if (_touch.Current.X < _thumbsCanvasInfo.ImageInfo.Rect.Left ||
_touch.Current.X > _thumbsCanvasInfo.ImageInfo.Rect.Right)
{
return;
}
// Check touch type
switch (args.Type)
{
case TouchActionType.Pressed:
_touch.Matrix = SKMatrix.MakeIdentity();
// Adjust thumbs bounds
_leftThumbDraw.Bounds = new SKRect
(_leftThumbDraw.Point.X - _leftThumbDraw.Radius, _leftThumbDraw.Point.Y - _leftThumbDraw.Radius
, _leftThumbDraw.Point.X + _leftThumbDraw.Radius, _leftThumbDraw.Point.Y + _leftThumbDraw.Radius);
_rightThumbDraw.Bounds = new SKRect
(_rightThumbDraw.Point.X - _rightThumbDraw.Radius, _rightThumbDraw.Point.Y - _rightThumbDraw.Radius
, _rightThumbDraw.Point.X + _rightThumbDraw.Radius, _rightThumbDraw.Point.Y + _rightThumbDraw.Radius);
// Check if the inner circle was touched
if (_leftThumbDraw.Bounds.Contains(_touch.Current) &&
_rightThumbDraw.Bounds.Contains(_touch.Current))
{
_touch.Id = args.Id;
_touch.Previous = _touch.Current;
_activeThumb = _lastActiveThumb;
}
else if (_leftThumbDraw.Bounds.Contains(_touch.Current))
{
_touch.Id = args.Id;
_touch.Previous = _touch.Current;
_activeThumb = ActiveThumb.Left;
}
else if (_rightThumbDraw.Bounds.Contains(_touch.Current))
{
_touch.Id = args.Id;
_touch.Previous = _touch.Current;
_activeThumb = ActiveThumb.Right;
}
break;
case TouchActionType.Moved:
if (_touch.Id == args.Id)
{
// Adjust the matrix for the new position
_touch.Matrix.TransX += _touch.Current.X - _touch.Previous.X;
_touch.Matrix.TransY += _touch.Current.Y - _touch.Previous.Y;
_touch.Previous = _touch.Current;
var value = GetThumbValue(_touch.Current);
// Check active thumb
if (_activeThumb == ActiveThumb.Left)
{
Thumbs.Left.Value = value;
Start = value;
}
else if (_activeThumb == ActiveThumb.Right)
{
Thumbs.Right.Value = value;
End = value;
}
// Update value
thumbsCanvas.InvalidateSurface();
}
break;
case TouchActionType.Released:
case TouchActionType.Cancelled:
{
_touch.Id = -1;
_lastActiveThumb = _activeThumb;
}
break;
}
}
