View Full Version : Question for Srek (or Xpresso people)

09 September 2006, 10:03 PM
I'm using the range mapper to drive a child in my hierarchy.
But would like to restrict it's movement on the Y Rotation axis (P) from -60 to 100
Is this possible?


Rantin Al
09 September 2006, 11:12 PM
Here's one solution, there are more depending on your control parameter.

I've used a data slider for the rotation of the null : 0>360.
Radian to Degree node > RangeMapper.
RangeMapper changes value to: -180 > +180.
Clamp Node set to -60 >100.
Degree > Radian Node > P Rotation.

It can be changed to scale the rotation proportionately with different settings.
HTH and gets you started anyway.
Cheers, Alan.

09 September 2006, 11:54 PM
Thanks man.

I'm going for the basics of this principal first, then will attempt something more complex. I will have a folding leg with 3 joints, but once the second joint reaches a certain rotation, the third joint will be in position and no longer needs to rotate.

I work a lot with TP, but the Xpresso side of things can be a little daunting.

09 September 2006, 12:23 AM
I do get some control with range mapper alone, but certainly not as much as I would like.


Sorry I always forget there's actually an xpresso side forum, my bahd.

Rantin Al
09 September 2006, 12:35 AM
You're welcome.

Best thing to do is dive into some simple stuff to begin with and pull apart every sample you can find.

Your three jointed experiment shouldn't be too difficult. Just work on it section by section and build it up. If you need any help with it just fire a flare :) and I'll help where I can.
(I'm no Srek but I can figure out some basics.)

Cheers, Alan.

Rantin Al
09 September 2006, 03:28 AM
OK, here is a little bit of what OD'ing on Xpresso does for you.

First a couple of tips:

* Put your Xpresso tag on a top level null and build your hierarchy under it. Easier access.
* Start your basic components zeroed out along one axis at 0,0,0. You can shift everthing into position via the Null once everything is grooving.
* Name your parts logically. Some of your spheres were under the wrong cylinder.
* I re-organized the whole set-up with the spheres as parents and cylinders as children.
* Re-centre the cylinder axis to the centres of the spheres and Expressofize the spheres.
* Don't keyframe anything until it is working staticly. Use a User Data Slider initially for the input. You can keyframe the slider as I have done in the sample.

Just press Play and enjoy.

Disable the Array once your eyes settle down.:argh::eek:
Then pull the Expresso apart. You can disconnect the primary link into each level and see how each set up controls the individual legs.

That should keep you out of mischief for a day or two.
Have fun, Alan.

09 September 2006, 04:54 AM
Thanks Alan,

real nice setup that will be usefull someday......
With this kind of examples Xpresso becomes more and more clear to me

Rich-Art. :thumbsup:

Rantin Al
09 September 2006, 12:23 PM
Hi Rich.

In itself, it is kind of general to the partial rotation of one object to another.
There are other nodes such as Event Trigger/ Timers which might be more elegant, but the sample shows some basics to play with.

Putting Result nodes into a simple set-up lets you see how things are being affected.

Cheers, Alan.

09 September 2006, 12:58 PM
Hi Alan,

Yes you're right about the result node, they are my friends at the moment. LoL
And playing with Xpresso is the best way to learn it...

Rich-Art. :thumbsup:

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