Vellum Targetting and targetweight, cant make it wrk. Help Please

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Hello, I am struggling with something.
In FEM, i could have targetP and targetstiffness, to drive sim with animation or not etc, and was very easy to use, so i am trying the same thing in vellum but i couldnt make it work.

In documentation of vellumattributes
https://www.sidefx.com/docs/houdini/dyno/vellumattributes.html [www.sidefx.com]
under targeting it says

(Point) The target path and point number for any pins when the Target parameter is set in Vellum Source. Ifpintoanimation is 1, the pinned points' position will be updated to match the specified target point on the target path geometry. If gluetoanimation is 1, both the position and orientation will be updated.

and a float of targetweight should adjust the strength, but i couldnt make this work its either on or off, anyone has an idea?
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I don't know whether vellum supports f@targetweight, I'd guess not, as Permanent constraints set mass to 0 so particles can't move and Stopped constraints set stopped attrib, so neither of those seem to allow for partial blend unless

every time I needed such effect I create Soft Pin constraint and just drive their stiffness by an attribute, that works pretty nicely
Tomas Slancik
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Method Studios, NY
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targetweight is from the documentation, so i assumed it would have worked, mass 0 does work, but then i need them to update their location based on animation. do you think overriding positions in DOPs may work ?
CG Supervisor / MPC Montreal
*********** https://gumroad.com/timvfx [gumroad.com] *************
Some Coding : https://github.com/tricecold [github.com]
Website : www.timucinozger.com
Reel : www.vimeo.com/user7844693
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tricecold
targetweight is from the documentation, so i assumed it would have worked, mass 0 does work, but then i need them to update their location based on animation. do you think overriding positions in DOPs may work ?

you can use Vellum Constraint SOP to create target constraints (Pin To Target) and if you check Match Animation, it will follow the animation of the target geometry
then depending on the Pin Type it will either be defined as
Permanent - sets mass to 0
Stopped - will keep the mass as it is, just set the stopped to 1, so you can release them later
Soft - creates actual distance constraint towards target positions
but regardless of the type all of them will still respect pintoanimation or gluetoanimation set by Match Animation checkbox and will follow animation of the target geometry

the only way I know how to emulate targetweight is with Soft pin constraint and stiffness from attribute as mentioned before
I'm not sure if vellum would use actual targetweight attribute for anything at the moment even though it is mentioned in the docs, maybe just copy/paste from cloth docs?

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vellum_target_pin_stiffness_by_attrib.hip (402.6 KB)

Tomas Slancik
FX Supervisor
Method Studios, NY
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