Vellum constraint rotation

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HI folks

I'm trying to build a feather (yes I know there are proper node in houdini 20, but can't affort it now)
I have created a line with other perpendicular lines
I put them together using vellum stich point but at the moment the simulation begins the perpendicular lines start rotating (as you can see in the video below)
(I tried with vellum attach to geometry, but the target geometry doesen't update its position, as well I tried simulating the target geometry first in a separate sim an then put together with the others lines but I got the same result. Vellum glue didn't work either)

I would like to know if there is a way to control that rotation
Thanks in advantage
Image Not Found
Edited by paniruro - 2023年12月28日 03:33:37

Attachments:
feather.mp4 (4.4 MB)
feather02.hiplc (517.4 KB)

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Hm...after yours group-pts make ...for each primitive and feed those wrangles ..

if (@ptnum <= chi("pin_group")) i@group_pin = 1;
float locate = float(@ptnum) / float(@numpt);
float ramp = chramp("stiffness_ramp", locate);
float pow = chf("stiffness_power");

f@stiffness = pow(fit01(ramp, 1.0, 2.0), pow);

change first hair constraint to Soft (matchAnim) then change Bend to scale by att (stiffness)
10*10000.
..
wind in force experiment with groups ..
..
Its based on your setup ..But if you make a little bit change with "Kinefx" naming and settings for constraint you can make rig attribute and then Change to
"3@transform = qconvert(p@orient);"
before vellum post proces in Loop..
..I need Time for that..

Attachments:
Hmedzczsdadf.gif (1.3 MB)

Conservation of Momentum
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cncverkstad
Hm...after yours group-pts make ...for each primitive and feed those wrangles ..

if (@ptnum <= chi("pin_group")) i@group_pin = 1;
float locate = float(@ptnum) / float(@numpt);
float ramp = chramp("stiffness_ramp", locate);
float pow = chf("stiffness_power");

f@stiffness = pow(fit01(ramp, 1.0, 2.0), pow);

change first hair constraint to Soft (matchAnim) then change Bend to scale by att (stiffness)
10*10000.
..
wind in force experiment with groups ..
..
Its based on your setup ..But if you make a little bit change with "Kinefx" naming and settings for constraint you can make rig attribute and then Change to
"3@transform = qconvert(p@orient);"
before vellum post proces in Loop..
..I need Time for that..


thank you very much for your help, it works but the feather spine is not moving
from you gif I can't see well if it is moving too
thanks again
Edited by paniruro - 2023年12月28日 06:53:19
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@paniruro What movement you Want exactly?
Could you please share a visual representation or image depicting that particular movement?

Feather it's Funny Geo.
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paniruro
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Hi @cncverkstad
as you can see from the video I attached in the first post ( feather.mp4 )
the vertical line (the spine of the feather) is moving because of the popwind.
that's the movement I need to merge with the solution you gave me.
Thanks again
Edited by paniruro - 2024年1月2日 04:41:18
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