private void FinishStroke(Stroke stroke)
{
//Seal stroke for better performance
stroke.Seal();
// Add finished stroke to the collection of finished strokes.
_finishedStrokes.Add(stroke);
// Remove finished stroke from the collection of strokes in drawing.
_activeStrokes.Remove(stroke.Id);
}
// Touch down event handler.
private void OnTouchDownHandler(object sender, Windows7.Multitouch.TouchEventArgs e)
{
// If there exist stroke with this ID, finish it.
Stroke stroke;
if(_activeStrokes.TryGetValue(e.Id, out stroke))
{
FinishStroke(stroke);
// Request redraw of the window.
Invalidate();
return;
}
// Create new stroke, add point and assign a color to it.
Stroke newStroke = new Stroke ();
newStroke.Color = _touchColor.GetColor(e.IsPrimaryContact);
newStroke.Id = e.Id;
// Add new stroke to the collection of strokes in drawing.
_activeStrokes[newStroke.Id] = newStroke;
}