Code

private void diagram_DrawNode(object sender, DrawNodeEventArgs e)
{
	// draw anchor point labels
	const double margins = 10.0;
	var node = e.Node;
	var rect = node.GetBounds();
	var pattern = node.AnchorPattern;
	if (pattern != null)
	{
		foreach (var point in pattern.Points)
		{
			if (point.Tag == null)
				continue;
			string label = point.Tag.ToString();
			var x = point.X * rect.Width / 100;
			var y = point.Y * rect.Height / 100;
			var size = diagram.MeasureString(label, node, 1000);
			var labelRect = new Rect(
				x - size.Width / 2,
				y - size.Height / 2,
				size.Width + margins,
				size.Height + margins);
			if (labelRect.X < 0)
				labelRect.X = 0;
			if (labelRect.Y < 0)
				labelRect.Y = 0;
			if (labelRect.Right > rect.Width)
				labelRect.X = rect.Width - labelRect.Width;
			if (labelRect.Bottom > rect.Height)
				labelRect.Y = rect.Height - labelRect.Height;
			diagram.DrawStyledText(e.Graphics, label, node, labelRect);
		}
	}
}