[Connectors] Cool, and how can I...

danielv at netvision.net.il danielv at netvision.net.il
Fri Apr 5 15:23:58 UTC 2002

Ned Konz <ned at bike-nomad.com> (by way of Ned Konz <ned at bike-nomad.com>)
> On Thursday 04 April 2002 08:23 am, Daniel wrote:
> > A few question/weird things that happen:
> > * When I duplicate an arrow (grab by green handle), the grabbed object
> > appears at a significant offset to the original. This is a bit annoying.
> > Ah, I just understood, it hands me the first connection point, so I can
> > start connecting immediately. This is the idea?
> Yes. You can then drop the first connection point on something.
What bothers me is that AFAICT, the green duplicate handle is pretty
fixed in meaning "you've just picked up a copy by it's green handle". So
I very much expect the green-grab not to immediately move the copy...

> Though
> duplicate on a connected line doesn't let you drag the line (I'm going to fix
> it so it disconnects the line, I think; what are your feelings on this?)
> What would you rather have it do?

How about distinguishing between a green handle grab (carry off a
disconnected clone) and a green handle click (start defining a line,
source first using crosshairs)?

Is this also usefully applicable to other morphs?
[Request for midarrow constraints]

> You can make a constraint object with an attached shape.
> Create a new NCConstraintMorph, attach it to where you want it, and say "add
> arbitrary shape". It will then copy the shape you select and add it to
> itself.
Hah! I tried that, by creating a bend in one of the arrow, doing show
handles, thus getting the constraint. Then I created an ellipse (didn't
know you had those NCEllipses, they're not in any flap - found them
looking for NCConstraint in new morph menu, which it doesn't show up
in), and did add arbitrary shape on it. This got me almost what I want -
the line did connect to the ellipse by the middle.

However, two things -
* The ellipse was connected to the line, not vice versa - I expect the
lines to be moved the ellipse, not the other way around... I don't think
I understand the idea yet.
* Like you said, this copies the ellipse. This means I'll never get what
I really want (and so obviously didn't mention ;-), which is several
lines passing through the same ellipse. Can you explain why the copy?
seems if I wanted a copy, I could do it myself before doing a pure

There are a few concepts that don't quite connect in my head -
* In morphic, morphs move with the parents. Constraints are also part of
the submorph heirarchy.
* but Constraints move with their inputs?
* Constraints affect the morphs in the "constrained" arrays by sending
them messages. right?

Is there a design overview somewhere?

> If you don't mind coding, the NCConstraintMorph (or OffsetConstriantMorph)
> could have a subclass that moves line vectors around. (is that what you
> want?).
didn't understand "move line vectors"..

> Or maybe I could get the LineEndConstraintMorph to work with other line
> vertices. I don't know how much work that is.
> > * A questions that's only somewhat related - I want to store my diagrams
> > outside the image, maybe in a BSS-like DSS (DanielsSuperSwiki), probably
> > to be kept internal.
> Make them separate projects, then just save the projects.
Yup, that's what I've been doing so far...
> > Any better ideas? how do I set up my own SSwiki?
> I don't know. However, I've had some success using a ComSwiki set up with
> project pages that make new drawings. One of the reasons I changed from using
> BlockContexts to MessageSends is so I could get this to work.
> The nice thing about this is that it allows collaborative work (I don't know
> what it does about concurrent edits, though).
Sounds great - since I already keep my hyper text notes in a ComSwiki,
that matches perfectly. So how do you edit a diagram that's in the
> Thanks for the feedback!
> BTW, what do you think about Connectors and:
> * orthogonal lines
So far, I don't need them
> * undo
Surprisingly, so far, I haven't needed that either ;-) but this would
certainly be great as a safety net.

> --
> Ned Konz
> currently: Stanwood, WA
> email:     ned at bike-nomad.com
> homepage:  http://bike-nomad.com

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