.bgeo sequences in MOPs

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lg3bass
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Joined: Sat Jan 05, 2019 5:29 pm

.bgeo sequences in MOPs

Post by lg3bass » Sat Jan 05, 2019 5:55 pm

Hi, MOPs is great! thanks for creating this toolset.

Question based on a comment that Toadstorm made in this thread: MOPS with SOPS:
The solution is to probably export a .bgeo sequence of your object bending over time, then load that into the Instancer using the File option. You could then use a template point attribute from the source points (you'd have to instance onto a template mesh for this to work) to control which frame of the sequence to load for each copy. You could start with a Falloff attribute on the template points, then remap it to a range of 1-(sequence length), then use that as your frame attribute on the Instancer.
I'm looking to animate individual instances of bgeo sequences . Is it possible to set the frame of each instance separately? Can you elaborate on the comment above. How would you set this up to drive the frame of each instance with a falloff value? Would love to see an example? Ultimately I would love to control individual instances with CHOPs channels or a midi track:D

I tried myself but I couldn't get it to work. All my instances are locked to the timeline. Maybe I'm getting tripped up on a fundamental as I'm new with Houdini. Here is my file.20190103_bgeo_sequence_forum.zip

thanks,

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toadstorm
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Re: .bgeo sequences in MOPs

Post by toadstorm » Sat Jan 05, 2019 7:35 pm

Yep, we have a dedicated SOP for this: MOPs Set Sequence Time. The only catch is that you need to make sure your Instancer is set to load Files instead of SOPs. There's a dropdown for each instance type in the Instancer multiparm called "Instance Type"... just select File and then point to the sequence on disk. Then set the frame range parameter to match the range of your sequence (1-30).

You had the right idea with creating a "frm" point attribute to define which frame to set each instance to, but you weren't animating the attribute... it was being set to

Code: Select all

(i@id*2)+1
, where you really need

Code: Select all

(i@id*2)+@Frame
to ensure that the index is changing over time. Then drop down a MOPs Set Sequence Time SOP, set the Index Type to "Attribute", then set the Attribute Name to "frm". You may also have to change the attribute type to "float" instead of "integer" for now, though that will be fixed in the next release.

One last thing... when loading sequences from disk, you have to point to files on disk, not SOPs, which means you can't modify the instances using SOPs ahead of time (like the Transform SOP you're trying to use in your original example)... if you want to make transform changes, do so using MOPs Transform after instancing, or alternatively, instance using an existing template object that has the @N / @up / @pscale attributes you want for the initial configuration.

I'm attaching a working version of your file.
Attachments
obj2bgeo_sequence_test_fix_toadstorm.zip
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lg3bass
Posts: 2
Joined: Sat Jan 05, 2019 5:29 pm

Re: .bgeo sequences in MOPs

Post by lg3bass » Sun Jan 06, 2019 4:43 pm

Thank you Toadstorm. Makes total sense. Lot of fun to be had with this method!! :D I foresee lots of animated gifs.

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