/// <summary>
/// Start user interaction logic, like MouseDown on control
/// If not pan mode draw point
/// </summary>
/// <param name="p">Start point</param>
public void PressDown(Point p)
{
if ((HasNoLayers)||(!SelectedLayer.IsVisible))
return;
_pressed = true;
_lastPoint = p;
if (!PanMode)
{
CheckLayerPostionAndSize(new[] {new Point(p.X, p.Y)});
var normalized = p.Normalize(SelectedLayer.Position);
SelectedLayer.DrawPoint(_brush, Thickness, normalized);
_points = new List<Point>();
_points.Add(p);
}
}