< Once you have disabled it and edited a curve without history updating on, that will then break the history chain and you won't be able to get it back with those particular curves.

< But you could delete one curve and remake the other one by doing a new Mirror operation to get it set back up again if that's what you wanted.

Not exactly this : I had wished recuparated the "symmetry" between A & B but with their new size A big, B small! Because curves were integrated inside the Lofted surface.
A sort of differential move inside the lofted surface A & B moving & growing in the same with the Edit Frame
So Seems impossible

OK It's that i wanted to know! : Thanks !

he he
I must just copy Move the 4 curves A,B,C,D (with the new A big, and B small) and make a new Loft!
That works fine for A & B, and it's not a big deal!
Sure that don't work more (symmetry) for C&D :)

But I can use the edit frame for refound a sort of symmetry :)

Hi Pilou,

> Not exactly this : I had wished recuparated the "symmetry"
> between A & B but with their new size A big, B small!

I see - so in order to make something like that with history you need to build a kind of chain of objects.

If you start with this object:



You can then mirror it:



Then select the mirrored result, and run the Transform > Scale command on it with the "Make copies" option enabled, to make a new curve that is a scaled copy of that mirrored one:



Now select the scaled object (make sure not to do any other edits to it like even move it around) and turn on history updates for it by Edit > History > Enable updates.

Now when you move the original curve, the other 2 curves will update.

But you can't delete the mirrored curve for this to work right now, because the way it works is:


Mirrored version knows it is made from the original curve, and recalculates when the original curve changes.

Scaled version knows it is made from the mirrored curve, and the scaled curve recalculates when the mirrored curve changes.


If you delete the mirrored curve, then the scaled curve won't know how to update becuase it is linked to the mirrored curve, and if the mirrored curve is removed that breaks the history chain.


- Michael

Cool stuff! The more I read here on the forum, and learn the ropes, the less I use Rhino (waiting for the flow command, and I could kick Rhino ... hint, hint ;)

I tried the sequence, and it all worked well for moving the objects, but history breaks when I edit the first curve. The mirrored curve updates, but not the scaled. I guess this is correct behavior, or did I something wrong?

Thanks,
Ditto

hi ditto

what do you mean by "edit"?..editing a child curve will break the history-dependency. so if you haven't touched one of them, the sequence should be intact.

check the example

http://screencast-o-matic.com/watch/cXhUj1FUt

cheers,
marco

Hi Ditto,

> I tried the sequence, and it all worked well for moving
> the objects, but history breaks when I edit the first curve.
> The mirrored curve updates, but not the scaled. I guess
> this is correct behavior, or did I something wrong?

Did you turn on history updates for the scaled curve? By default scaled objects do not have history updates turned on for them, so you have to turn it on by selecting the scaled result and running the Edit > History command and turning on "enable update".

Then with history updating enabled on that object, it should update when you edit the first curve, as long as you didn't do any other operations on it like try to move the scaled curve around.


The kind of tricky part about the history chain is that all the objects involved in the chain need to be currently present in the model for them to be updated. Moving an object is basically like deleting the current version of an object and replacing it with a different transformed version. That will work to edit the objects at the very start of the chain, to trigger an update but it won't work if you move some piece in the middle of the chain.


By the way, Flow is definitely high on the target list for v3...

- Michael

hi michael

is there a way to determine, whether a curve/object has "a history"?..right now, i can't spot any visual feedback or indicator. even if i call the history command, both buttons do look the same..

thank you,
marco

Hi Marco, there isn't anything in the UI to show it right now - in the future I definitely want to have something that would both show it and allow you to edit it like change parameters and stuff like that, but it's a pretty big area of work.

I think it could be possible to make a script that could be assigned to a keyboard shortcut that would pop up a message if the selected object had history data attached to it, would that be of any help right now?

Basically the history data is a chunk of text that stores the name of the command that was used to create the object and also a list of all the parameters that were used.

So that data will usually be present, even for stuff where there is not a way to edit it to update it currently.

- Michael

hi michael

ah, i see..

..an array must be something different than, because i can't get it to work with history. maybe(in future releases) there could be an option (pretty much alike the "make copies" button) to predefine the history-status of the "offsprings".

thanks,
marco

p.s. is it possible to embed iframes into a post?..

Hi Marco,

> ..an array must be something different than, because
> i can't get it to work with history. maybe(in future releases)

Yeah the history data is stripped on the output of Array, because there were some circumstances where having the data attached to each array output was increasing the size of files by quite a bit when arraying a large number of simple objects.

In the future I'd like to make that better - it may be better to store history data in some kind of centralized log of actions, rather than having attached data on every output object.

> there could be an option (pretty much alike the "make copies"
> button) to predefine the history-status of the "offsprings".

Yeah I've been thinking that there could be a setting in moi.ini where you could list commands that you wanted to have history updates turned on by default for.


> p.s. is it possible to embed iframes into a post?..

No, I think that the forum software strips those out since they are a potential security hazard.

- Michael