Cycle simulation

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How would one approach this problem? The problem I'm talking about is a waving flag, a moving rope or hair, you name it - first frame needs to be the last.
I remember that quite a while ago I did this in Softimage by copying and renaming the first (or few first) cache frame to also be the last and made the sim read the files instead of resim with each play. I'm thinking that there's a more elegant solution than that in Houdini. Is there?
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i haven't got a example file but look at blend shapes sop. with that node you can transform the animation to the beginning.
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Will look into it, thanks. Although, blend shapes… you sure?
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The Blend Shapes SOP simply blends point positions and other attributes. It doesn't care if it's static geometry or a sequence as long as the point count doesn't change or you provide an id attribute.

Say you have a finished sim from 1 to 240 with a waving flag and you want a continuous 100 frame loop after the end. What you would do is offset the sequence with a TimeShift SOP ( $F -100 ) and blend that with the original from 140 to 240. So when you arrive at 240 you have the same frame as 140. Then you cycle ( Motion FX ) from 141 to 240 and have a flag that never stops waving, because it likes to party all night. 8)

Attachments:
party_flag_loop.hip (127.5 KB)

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Thanks blackpixel.
I'm not able to open .hip with my free license though. AFAIK the Apprentice can open only .hipnc, unless I'm mistaken?
Anyway, your explanation is helpful.

edit: nvm, it seems that I am able to open it.
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Didn't want to start a new thread for this, so I'll ask here:
doesn't H have a >>| (jump to last frame) like the |<< one?
Would make my life a lot easier and for that matter for any animator that wants to compare the first/last frame of a cycle.
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if you Ctrl+Alt+Shift click to |<< Hotkey Manager will pop up, where you will see it's hotkey (Ctrl+UpArrow)
just a few lines above it there is Jump To End Of Range (>>|) just click on it and assign hotkey, like Ctrl+DownArrow

not sure if you can enable the button in UI though
Tomas Slancik
FX Supervisor
Method Studios, NY
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Alright, thanks tamte.
This button needs to be put up there though.
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Submitted a RFE for adding the button.
ctrl+UP for end of the timeline and ctrl+DOWN for the start makes more sense to me than ctrl+UP for start
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McNistor
How would one approach this problem? The problem I'm talking about is a waving flag, a moving rope or hair, you name it - first frame needs to be the last.
I remember that quite a while ago I did this in Softimage by copying and renaming the first (or few first) cache frame to also be the last and made the sim read the files instead of resim with each play. I'm thinking that there's a more elegant solution than that in Houdini. Is there?

Hi,
Actually on soft the method is exactly the same, cache the sim then, use two cache on file with a delay on the second, then animate the “blend” on the second one, softimage is elegant too ;-)
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