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Inflating lightweight fabric - how to approach this..?


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I'd like to make something like this video between approx 1:25 - 1:55 and I'm not sure how best to approach it.




I don't have much cloth experience and I've read various people saying that Maya nCloth is better, faster etc than Houdini cloth. But I wondered might this be something that wire could do?


Does anyone have any pointers as to where I should start investigating?


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just force attribute (or fexternal in H12.5) attribute applied in normal direction within SOP Solver should take you most of the way

just make sure you update normals (Facet SOP) prior to computing force if you are using CVEX based VOPs/wrangle nodes

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Thanks for the reply Tomas, I still don't really know where to start though.


The balloon at the beginning is very tightly scrunched up then expands first linearly, and then gains volume. So I wonder do I need to first make a 'final state' geometry for the fully inflated end point, then somehow collapse that to the inbetween states, essentially do the animation in reverse and then use them as goal objects in a sim?


Would you recommend cloth or wire for this? Or nCloth? Or am I totally missing something? It just seems to me like screwing it up into a tiny space will give me all sorts of collision problems. Or do I get around that with a SOP solver setting noCollide attribute in a wire sim for example?


Thanks - any clues greatly appreciated..

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I've spent a couple of days experimenting with different methods for this shot. I found an old thread regarding inflating an airbag - http://forums.odforce.net/topic/11497-simulating-an-airbag/?hl=airbag - which gave me a pointer about rest position but I don't think it's a suitable method to inflate something in different stages like this.


[here by the way is the footage I'm trying to recreate - http://youtu.be/wqaGOyh0B3E?t=1m22s]


My method so far is to do an initial wire sim going from very small, compressed then opening up to a long line with some noise deformation.  Maybe there's no need for this stage to be in DOPs.


Then I'm copying metaballs to the wire in SOPs to generate some thickness to the geo, then I start to inflate it using deformed rest positions.


It's just very basic sketches so far but It sort of looks like it might be a viable method with a LOT of tweaking - but I don't really know where to go from here. And I suspect that there's probably a much better way to approach it.


If anyone has any input I'd really appreciate it.

Thanks very much


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