Bone channel offset

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Quick question about CHOPS.

I created a bone chain with a wave running trough the ry channel. How do I offset the channels for each of the bones in CHOPS?
Edited by Werner Ziemerink - April 6, 2017 06:17:13

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Bone_Ch_offset.hip (224.6 KB)

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Hi Werner,

Is this the kind of thing you're going for?

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Bone_Ch_offset_possible.hip (231.7 KB)

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That is perfect. Thanks!


I got it to kind of work by doing something else, but was not sure if it was the correct way.
Edited by Werner Ziemerink - April 6, 2017 06:27:39

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Bone_Ch_offset_fixed.hip (226.4 KB)

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Cool! Wasn't sure if that was the desired effect. There are (of course ) loads of ways to get it sorted, but that's a fairly pure CHOPpy way of doing it. That fan CHOP mystified me for ages, but when you actually find a use for it, that's when it went ‘click’. Can be really handy in combination with doing any kind of integration on a channel (area CHOP) if you want to emulate a simple state machine.
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Oh yes, yours is much cleaner! Nice

Although, I'm amazed your network isn't erroring. I've experienced really unpredictable behaviour using a fetch on the same channels that I later export to…
Edited by friedasparagus - April 6, 2017 06:39:06
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Oh yes, yours is much cleaner! Nice

Although, I'm amazed your network isn't erroring. I've experienced really unpredictable behaviour using a fetch on the same channels that I later export to…


Hmmm, that makes sense. I can see why you generated a sine wave and just exported to the ry channels without using the fetch chop.

Now I need to go read up on the fan chop.
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Yeah, the reason I often WANT to use a fetch in this instance is just for naming reference, but like I said, has given me issues before…

Couldn't help trying another technique. This time using the shuffle to get all the output channels from a single wave channel.

EDIT: big bonus with this one is that you get a nice starting frame, rather than having to wait for a first cycle to complete
Edited by friedasparagus - April 6, 2017 07:07:05

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Bone_Ch_offset_possible2.hip (231.9 KB)

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Wow, thanks a lot. I'm sure this post will help other people as well.
Edited by Werner Ziemerink - April 6, 2017 07:24:24
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It was this vimeo video that sparked my interest. Hopefully we will see more on Chops in the new rigging masterclasses.

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Ha, great! My own little video was far more humble (and more dry-techie ), but was aimed more as a way to get people started in using CHOPs for this kind of thing. People seemed to like it though, so I must try and get round to doing the next one.

I'd love to know if there was anything in particular you think would be useful to cover.

I was also trying not just to aim it at ‘procedural’ animation workflows, as this a) isn't completely my bag and b) I wanted to make sure that people began to think of these tools in the context of more ‘traditional’ keyframe animation. Think that it puts a lot of animators off houdini if they think that ‘if it ain’t procedural, it can't live here'
Edited by friedasparagus - April 6, 2017 07:42:26
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The rigging with CHOPS video you did was awesome. We were watching that before playing with channel offsets.

That and the link I posted in my previous post fueled allot of ideas among our team. Coming from Softimage this was really helpful, and anything CHOPs you post, we will follow.
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Best news ever! Really happy it was helpful in some way. CHOPs is definitely an exciting area, and in need of a profile boost I feel! And the associated tlc that comes with it
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stop distracting me from my work!
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That was the Master(Class) plan!
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OUCH!
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I have never looked into CHOPS but after reading (seeing) what was here I applied the .hip to a whale model I had. Looks awesome but I have some questions if thats ok.

When I apply CHOPS to the bones I select all of them and right click> Motion FX> Wave.

It creates a setup a little different to the hip that was on the thread.
Is the set up correct in the picture?

Also animation curves usually have some delay, ramping in and out. Can this be applied to add more sense of weight to the movement?

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whale.jpg (209.5 KB)

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Nice thread!

After Henry showed me some chop wrangle tricks, that's been my favourite goto for this kind of thing. Plus nothing makes you feel so smug as a good one liner wrangle with a slider.

chinput() Lets you look up a sample from a channel. To set the Value based on the current Channel and the current sample Index (ie, leave the data as-is), is

V = chinput(0,C,I);

To offset the sample index per channel, add the channel to the index:

V = chinput(0,C,I+C);

Now you can multiply C by a slider to dial in the amount of lag, 0 is no lag, 1 is a standard amount, you can go above one to get more snake-like motion.

V = chinput(0,C,I+C*ch('offset'));

Click the little ‘make sliders’ button, done.
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Awesome love the sliders!

I set it up but not sure if its correct, any reason why the animation tries to return to the first keyframe at the end? Attached Hip file.

QUESTION. The math node looks like its used to add, blend information fed into it. Is it possible to have a bone chain moving say on the Y axis via a wave node and then add a subtle x axis movement to this again using a wave? Or even add jiggle to bones?

CHOPS has so much potential and I didnt even know about it for ages hahaha so much to learn.

Cheers,

Duncan

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boneChops.hipnc (121.5 KB)

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Hmm, not sure whats going on with yours, works for me (see attached).

Re rotate x, I did a very hacky method in that same file. What I find annoying is that chops gets confused easily, I have to frequently bypass/enable the wrangle to make it work. Hmm.

Attachments:
chops_bone_wave.hip (115.1 KB)

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Hi guys!

Just playing catch up on the files There's a bit of a gotcha on using the fetch CHOP for grabbing channel names - it generates a weird ‘silent’ dependency loop (that'll be why you keep having to bypass things to get it to update). I normally get around this with a constant CHOP, connect the fetch to the first input and hit the ‘Snapshot Input’ button on the constant CHOP, this'll give you a set of correctly named channels without any dependencies. The pain is that you then have to disconnect the fetch CHOP in order to clear any errors, would be great if the Constant CHOP snapshot worked just like the Stash SOP (I have submitted a bug/RFE about it).

Loving that last wrangle though Matt
Edited by friedasparagus - July 25, 2017 04:22:34

Attachments:
chops_bone_wave_constCHOP.hip (144.4 KB)

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