How to set various pressure values in vellum

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Currently I can add the same pressure to multiple spheres, what has been bothering me lately is how to apply different pressure values in the simulation (e.g. 5 for the red sphere, 2 for other colors), or set different stretch values for the cloth, I Thinking they're similar in principle.

I've tried looking up information, but haven't been able to find an introduction to this. Do you have any good solution? Thank you for your help!



Edited by HenDaSheng - Oct. 31, 2022 12:24:11
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You could activate Use VEXpression. Add a custom id to identify each sphere, and supply an alternate value to restscale over time.
if(i@my_id==0){restscale = fit(@Frame,1,48,1,10);}
if(i@my_id==1){restscale = fit(@Frame,1,56,1,4);}
if(i@my_id==2){restscale = fit(@Frame,1,60,1,30);}
if(i@my_id==3){restscale = fit(@Frame,1,24,1,9);}
if(i@my_id==4){restscale = fit(@Frame,1,72,1,17);}
Using Houdini Indie 19.5.
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Enivob
Enivob
Thanks for your help, I'll do some concrete tests next, thanks a lot!
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Enivob
You could activate Use VEXpression. Add a custom id to identify each sphere, and supply an alternate value to restscale over time.
if(i@my_id==0){restscale = fit(@Frame,1,48,1,10);}
if(i@my_id==1){restscale = fit(@Frame,1,56,1,4);}
if(i@my_id==2){restscale = fit(@Frame,1,60,1,30);}
if(i@my_id==3){restscale = fit(@Frame,1,24,1,9);}
if(i@my_id==4){restscale = fit(@Frame,1,72,1,17);}

According to the idea you provided, I first defined the id attribute for each sphere.

And then set different restscales according to the id attribute through VEXpression in slover.

But the result does not seem to identify "i@my_id>4", may I ask why?


Looking forward to your reply
Edited by HenDaSheng - Nov. 1, 2022 03:15:35
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It's probably because the "i@my_id" needs to be a prim attribute not point. (you can promote it after your copy to points)
Vellum constraint properties runs over prims, so it cant find your id attribute
Edited by AslakKS - Nov. 1, 2022 07:37:37
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AslakKS
It's probably because the "i@my_id" needs to be a prim attribute not point. (you can promote it after your copy to points)
Vellum constraint properties runs over prims, so it cant find your id attribute



Thank you for your reply. I tried to add "attribute promote", but it still doesn't work. Is there something wrong with my "attribute promote" setting?
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