GoGeneralNode position when adding/removing ports

GoDiagram (6 and previous)
1
When adding/removing ports to a GoGeneralNode, the node center stays in the same location, causing the node to grow 'outwards' from (or shrink 'inwards' to) the center.
I my case, I would like the node to grow at the bottom, retaining the top left position when adding/removing ports.
What is the best way to achieve this ?
2

Do you want the icon to scale to fit the ports, or stay fixed size? If you want a fixed icon, do you want it centered or top justified?

3

The icon should scale the way it does now, but the top left of the icon should stay fixed rather than the center.

4

OK, without overriding GoGeneralNode, you could just save the topleft, and then reset it after adding the port.

PointF tl = ng.Icon.GetSpotLocation(GoObject.TopLeft);
GoGeneralNodePort p = new GoGeneralNodePort();
ng.AddLeftPort(p);
ng.Icon.SetSpotLocation(GoObject.TopLeft, tl);
A cleaner solution would be to override LayoutChildren, and essentially do the same thing. (remember the topleft, call the base method, then move the node to location.)
5

This works, except that when undoing/redoing, the toplabel position is messed up.

6

You need to wrap any edits in


doc.StartTransaction();
...
doc.FinishTransaction("add port");