private static Vector DraggedDelta(InputDevice inputDevice, Window window, UIElement relativeTo)
{
// get the current position
Point currentPosition = inputDevice.GetPosition(window);
// get the down state
if (!deviceStateDictionary.ContainsKey(inputDevice))
{
return ZeroVector;
}
// translate to the relativeTo elementToDrag
Point downPosition = deviceStateDictionary[inputDevice].Position;
if (relativeTo != window)
{
currentPosition = window.TranslatePoint(currentPosition, relativeTo);
downPosition = window.TranslatePoint(downPosition, relativeTo);
}
return (currentPosition - downPosition);
}
private System.Windows.Media.Color GetPixelColor(InputDevice inputDevice)
{
// Translate the input point to bitmap coordinates
double transformFactor = ColorWheel.Source.Width / ColorWheel.ActualWidth;
Point inputPoint = inputDevice.GetPosition(ColorWheel);
Point bitmapPoint = new Point(inputPoint.X * transformFactor, inputPoint.Y * transformFactor);
// The point is outside the color wheel. Return black.
if (bitmapPoint.X < 0 || bitmapPoint.X >= ColorWheel.Source.Width ||
bitmapPoint.Y < 0 || bitmapPoint.Y >= ColorWheel.Source.Height)
{
return Colors.Black;
}
// The point is inside the color wheel. Find the color at the point.
CroppedBitmap cb = new CroppedBitmap(ColorWheel.Source as BitmapSource, new Int32Rect((int)bitmapPoint.X, (int)bitmapPoint.Y, 1, 1));
byte[] pixels = new byte[4];
cb.CopyPixels(pixels, 4, 0);
return Color.FromRgb(pixels[2], pixels[1], pixels[0]);
}
public static void InitializeDeviceState(InputDevice inputDevice)
{
if (inputDevice == null || deviceStateDictionary.ContainsKey(inputDevice))
{
return;
}
Window window = inputDevice.ActiveSource.RootVisual as Window;
if (window == null)
{
return;
}
Point position = inputDevice.GetPosition(window);
DependencyObject directlyOver = inputDevice.GetDirectlyOver() as DependencyObject;
deviceStateDictionary.Add(inputDevice, new DragState(position, directlyOver));
}
