| v e1 e2 e ctrlShape ctrls ctrl shape  addBlock |
v := RTView new.

e1 := (RTEllipse new size: 30) elementOn: 'A'.
e2 := (RTEllipse new size: 30) elementOn: 'B'.

ctrlShape := RTEllipse new size: 10; color: (Color purple alpha: 0.3).
"collection holding all control points INCLUDING starting & ending"
ctrls := (ctrlShape elementsOn: (1 to: 2)).

v
    add: e1;
    add: e2;
    addAll: ctrls.
v elements @ RTDraggable.

e := REEdge from: e1 to: e2.

ctrls do: [ :el | el addConnectedEdge: e ].

ctrls
    addFirst: e1;
    addLast: e2.

ctrls @ (RTLabelled new text: [ :el | el ]).

shape := RTMultiLine new color: Color blue.
shape block: [ :fromPoint :toPoint |
    | points |
    points := ctrls collect: [ :el | el position ].
    points asArray.
].

ctrls first translateBy: -50 @ 100.
ctrls second translateBy: -50 @ 0.
ctrls third translateBy: 50 @ 0.
ctrls fourth translateBy: 50 @ 100.

e + shape.

v add: e.
e trachelShape pushBack.

v open.

ctrls inspect.

addBlock := [ :point |
    | index |
    "find between which control points are we adding a new one"
    index := (2 to: ctrls size) detect: [ :i |
        | fromPoint toPoint |
        fromPoint := (ctrls at: (i - 1)) position.
        toPoint := (ctrls at: i) position.
        point onLineFrom: fromPoint to: toPoint.
    ].


    ctrl := ctrlShape elementOn: 'X'.
    v add: ctrl.
    ctrl @ RTDraggable.
    ctrl addConnectedEdge: e.
    ctrl @ (RTLabelled new text: [:el | el ]).
    ctrl translateBy: point.
    ctrls add: ctrl beforeIndex: index.

    shape block: [ :fromPoint :toPoint |
        | points |
        points := ctrls collect: [ :el | el position ].
        points asArray.
    ].

    "reset all the things"
    v removeEdge: e.
    e resetShape.
    v add: e.
    e trachelShape pushBack.
    v signalUpdate.
].

e when: TRMouseRightClick do: [ :event |
    addBlock value: event position.
].