Distance between AvoidNodes link and node

I found Orthogonal AvoidNodes links overlap top boundary of nodes, but keep a certain distance from bottom boundary of nodes.
All the nodes are rectangular.
How can I set the these distances? I would like to make these links always keep a specified distance from node boundaries.

Thanks, walter. You are always very helpfule to me.

You can override GoDocument.GetAvoidableRectangle to return a slightly different RectangleF for your nodes.
Here’s what it does by default:
public virtual RectangleF GetAvoidableRectangle(GoObject obj) {
RectangleF rect = obj.Bounds;
obj.ExpandPaintBounds(rect, null);
return rect;

Thanks. It works for me.