[Sidefx-houdini-list] Create attribute (primuv, primnum) similar to scatter sop does?

Michael Dunkley mdunkley at gmail.com
Wed Feb 12 16:02:23 EST 2014


In my experience, yes - considerably faster and more exact.  Lattices
always involves averaging between multiple points, but barycentric lookups
are just that - lookups - no interpolation beyond the specific polygon the
point is stuck to.  Last I was on a bird feathering project where we
switched the rig from a point lattice to barycentric uv lookups - the
feathers stopped floating off the skin and the whole thing was at least 10
times faster. i pretty much use that type of setup wherever i can.

m


On Wed, Feb 12, 2014 at 3:54 PM, Dominik Kirouac <dk at shedmtl.com> wrote:

> Thanks Mike,
>
> xyzdist is exactly what I was searching, it should be more precise than a
> lattice using point method?
>
>
>
>
> *Dominik Kirouac // SHED **
> *FX Artist
> 1410, RUE STANLEY, 11E Étage MONTRÉAL (QUÉBEC) H3A 1P8
> T 514 849-1555 F 514 849-5025 WWW.SHEDMTL.COM <http://www.shedmtl.com/>
>
>
> Le 12/02/2014 3:15 PM, Michael Dunkley a écrit :
>
>  Hey Dominik, the easiest way I know of is the "xyzdist" VOP / Vex
>> function.
>>   It'll find the closest position on a geometry to your point and give
>> back
>> the barycentric coordinates.  "intersect", the VOPS version of ray, should
>> also work, so long as you know the vector you're projecting along.
>>
>> Best,
>> Mike
>>
>>
>> On Wed, Feb 12, 2014 at 3:03 PM, Dominik Kirouac <dk at shedmtl.com> wrote:
>>
>>  Hey all,
>>>
>>> Here is the problem, we have curves (hairguides) import from another
>>> software(xsi) with alembic. We create a group of points with the root of
>>> each hair and we are trying to make this group stick to the deforming
>>> geometry.
>>>
>>> I want to replicated one of the behavior of the scatter sop(create primuv
>>> attribute on points and primnum).
>>>
>>> Is there a way we can get these informations from the closest geometry
>>> using a ray sop or expressions ?
>>>
>>> Thanks
>>>
>>>
>>> *Dominik Kirouac // SHED **
>>> *FX Artist
>>> 1410, RUE STANLEY, 11E Étage MONTRÉAL (QUÉBEC) H3A 1P8
>>> T 514 849-1555 F 514 849-5025 WWW.SHEDMTL.COM <http://www.shedmtl.com/>
>>>
>>> _______________________________________________
>>> Sidefx-houdini-list mailing list
>>> Sidefx-houdini-list at sidefx.com
>>> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>>>
>>>  _______________________________________________
>> Sidefx-houdini-list mailing list
>> Sidefx-houdini-list at sidefx.com
>> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>>
>
> _______________________________________________
> Sidefx-houdini-list mailing list
> Sidefx-houdini-list at sidefx.com
> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>



More information about the Sidefx-houdini-list mailing list