Cineversity

I hope the title is kind of explanatory…

I am re-rigging a cartoony water drop I started on a while ago and I realised my previous rig was way to limiting.
What I am trying to achieve this time is a rig where an animator would have enough control to make the drop feel super fluid!

For the body I would like to try to have these levels of control:

1 - Spline Wrap control for deformation of ALL the body (Spline has 3 nulls Ctrls)
2 - Spline Wrap control for extra level of deformation if needed (Spline has 5 nulls Ctrls)
3 - Body shape is created by a spline inside a Lathe Nurd object (Spline with 7 nulls Ctrls)

So basically I want a rig that starts with the deformation of the Body Shape spline, that is then deformed by the extra spline deformation. Then all of this is again deformed by a main spline.

I’ve rigged it up a with a simple Spline, Spline Wrap and Null hierarchy + xpresso (to attach nulls to spline points)
It kind of works BUT I have two problems:
- my main problem is getting the Null Ctrls that I have attached to level 2 and 3 to “move” into Spline Wrap deformed space.
- my other problem is that the Nulls from level two doesn’t seem to be completely attached to the spline

Any ideas?

I have attached a simplified version of the rig if someone has time to look at it.

I have named each level according to my explanation here (1, 2, 3) so make it simpler to follow.
The 3. level I have ignored for this example. I am guessing that if I get Level 2 to work, this should be easy to implement later on.
(I have also an extra level of Nulls to add Spring to Level 1 deformation)

Franck

Hi Franck,

Let me try to get this defined in a Nut-Shell: The three main Nulls are supposed to establish the main constellation/animation, and the five detail Nulls are supposed to work as minor adjustments.

This would result, if understood correctly from my side, in a hierarchy, parent = main and child = detail. Well that is not a given in your set up and hence the detail Nulls take over and leave the Main Nulls outside of the game.

The key here would be to understand the needs completely. There is always something that needs to be adjusted later on and not following a hierarchy. In other words, as long as the “detail” Nulls have so much power, they will tear apart your rig.

One of the key questions is here, how to connect the detail Nulls with main Nulls. As they can’t just be set up like a tree, with twigs, as the end of the twigs have to follow the next branch as well, if I apply a tree to your drop set up. (I hope that analogy makes sense)

I assume here it is a flow, so the main Null that is on position one has more power than the one on position two. Then the simple branch/twig idea would work. If not you need to use, for example, a Constrain set up. The detail Nulls follow so the position of the main (neighbor) Nulls. The problem here will be that the detail follow the Constrain and not a manual user idea. To overcome this, the Null that is between two main Nulls will be based on the Constrain and the two resulting parameters to find the position between those. The two sliders of that Constrain Tag allows to move the detail Nulls to a certain position. This Null is then a parent to the detail Null, which can be moved freely, but follows its two “parents” based on the constrain.

BTW, Instead of setting up the Spline/Null combinations with XPresso, throw all Nulls into a MoGraph Tracer and use Connect Objects.

IF you like to have a rail for the work, use child Nulls on the main (perhaps detail as well) with a distance to them each time. So the rail is created and via R.H the rail can be adjusted.

I hope that makes sense. The main Nulls keep the main control, but there is enough for the detail Nulls to work as well on a secondary level.

The ideal scenario would be that the detail Null find a position among the main (neighbors each time) and have a vector-user data GUI 2D for the movement perpendicular to the vector the two main Null create. The Rail might be useful then for the “Up Vector/Aim orientation.

As a side note, a Spline IK - joint set up might work as well.

All the best

Sassi

P.S.: ...just a thought, a very simplified way to do it—based on your scene file. The Main (top, middle, low) create a Tracer spline, which is the “back-bone” for the details (via Align to Spline). These have child objects (the detail CTRL Nulls) which can be moved freely, but follow the Main Null Results as far as possible, to allow for the detail-freedom.

These Detail/CTRL Nulls go then again into a Tracer (check the hierarchy in the Object Manager!) to create a new Spline—which is then fed directly into the Spline Wrap to deform the Object. Less steps between, more control.

I have set the Layer Browser in a way that only the controls are visible in the OM.

I hope that helps.

Hi! Thanks for your quick answer

And thanks for your tip about using Nulls and the Tracer. It is actually a much simpler setup

To see if I understand exactly what you are justing, I have created a new scene.
This is just a v1 without all the extra stuff for now.

I have used your constrain suggestion (did you mean with Parent Constrain?) and I think it might work ok.
I am seeing two problems right away though:
1 - As Detail Null 2 & 4 (Level 2) are middle constrained between Main Null 1&2 and Main Null 2&3, They will always have a direct/straight position between them. If they where linked to a spline f.ex. they have more of a position in the shape of a curve. How can one add this functionality?

2 - Creating a reset button for the Detail Nulls (Level 2) might be a bit difficult… But I might link that up to an xpresso setup where it looks for the current position of the Main Nulls (Level 1) and feed that to them. Nulls 2 & 4 would be setup like the constrain tag with a middle position of Main Null 1 & 2 and Main Null 2 & 3. Would that be the best?

PS: I know I could have done this with Spline IK but if I tried something similar at first and it was a bit limiting in terms of having to have a polygon object to deform. I setup loads of morphs and everything but in the end the rig became to rigid. Unless you mean rigging this another way?

I didn’t see your latest post before I posted this example but this seems to be simplest and maybe even cleanest way to set this up.
It definitely solve both of the problems I was mentioning above…
It’s easy to implement a reset button and then Detail Nulls follow the curved deformation.
This should be easy enough to implement on the third level of details as well I think…

Hmmm… The one thing I didn’t understand completely is your explanation of the rail setup.
In my mind I would create some new Main Rail Nulls with the offset you mention and then maybe setup them up with an User Data (+Xpresso) so that the user can make them rotate relative to the Main Nulls and choose a direction. Does that sound like a good setup?

Franck, here is a simple scene with the Rail-“idea” that I have had mentioned.

As the Null objects (main) need only a position to get the Tracer Spline going, the rotation of the Null can be used to manage the Rail components of it. The rail Nulls are each time a child to the main. In that way you handle all (per Null pair: main and rail) with one active object: no selecting another object to get it done, just using the keys E and R to switch the mode ;o)

I guess the example file is better suited to explain it.

Have a great weekend

Sassi

Seems like a good setup!

Thank you so much for your help! It’s really good to have a second head with these kind of things. Sometimes one thinks a little to complicated

Have a great weekend as well!

As for me… Back to rigging!
(I have quite a lot more to explore here;)

You’re welcome, Franck! :o)

Complicated—it is mostly based on thinking in steps and build up a solution, start to end. Each previous step might support or slow down the solution-finding. To come later in, and see one set up, as well as explore it from the end—backwards is sometimes simpler (which was my part here ;o)

Have a good one

Sassi