Vellum tetrahedral + weld points - welds dont want to break

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Hi

I am trying to create a vellum softbody object that falls apart on impact.

I have my pieces with tetconform and tetrahedral constraints. Then add a weld on the edges of the outer shell.
For some reason the combination of tetrahedral and weld points makes the welds unbreakable.

It's important I use tetrahedral for this project.
Any ideas why this might be happening?

Attachments:
houdni_head_stripped.hiplc (889.7 KB)

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Hi,
to break weld constraint 'weld' point attribute on a geometry (not constraint) has to have value -1.
I.e. vex code:
if(@Frame>9) i@weld = -1;
in a popwrangle dop should work in your example.
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vicvvsh
Hi,
to break weld constraint 'weld' point attribute on a geometry (not constraint) has to have value -1.
I.e. vex code:
if(@Frame>9) i@weld = -1;
in a popwrangle dop should work in your example.
Thank you for the input, your solution is equicalent to just turning the welds off so not really what I am looking for.
I want to break the welds based on the stretch stress etc. It works really well with struts but somehow in tetrahedral it doesn't I am not really sure why.
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pitapan
vicvvsh
Hi,
to break weld constraint 'weld' point attribute on a geometry (not constraint) has to have value -1.
I.e. vex code:
if(@Frame>9) i@weld = -1;
in a popwrangle dop should work in your example.
Thank you for the input, your solution is equicalent to just turning the welds off so not really what I am looking for.
I want to break the welds based on the stretch stress etc. It works really well with struts but somehow in tetrahedral it doesn't I am not really sure why.
There is no stretch stress generated from tetrahedral constraints, as a workaround you can add Distance Constraints at least to the outside polygons which are welded and set it's Stiffness to 0

That way it should not affect your sim but you should be able to use Stretch Ratio it Stretch Distance breaking type on welds
Tomas Slancik
FX Supervisor
Method Studios, NY
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