public static GraphicsPath GetRoundPath(Rectangle r, int depth)
{
GraphicsPath graphPath = new GraphicsPath();
graphPath.AddArc(r.X, r.Y, depth, depth, 180, 90);
graphPath.AddArc(r.X + r.Width - depth, r.Y, depth, depth, 270, 90);
graphPath.AddArc(r.X + r.Width - depth, r.Y + r.Height - depth, depth, depth, 0, 90);
graphPath.AddArc(r.X, r.Y + r.Height - depth, depth, depth, 90, 90);
graphPath.AddLine(r.X, r.Y + r.Height - depth, r.X, r.Y + depth / 2);
return graphPath;
}