[Sidefx-houdini-list] uv's along a nurbs spline
dan.seddon at framestore-cfc.com
Mon Jan 30 15:58:33 EST 2006
You can use the Measure Sop to calculate the "Perimeter" then multiply
this against the uv's you've just made and that should give the length
along the spline. You can use Attribute Promote to get the Perimeter
Attribute into the context of a point expression easily.
>So is there no way to get it to calculate the
>actual length? Only the linear values?
>PS I figured the maya comment would get people to respond furiously fast.
>----- Original Message -----
>From: Dan Seddon <dan.seddon at framestore-cfc.com>
>Date: Monday, January 30, 2006 12:48 pm
>Subject: Re: [Sidefx-houdini-list] uv's along a nurbs spline
>>Phillip P Prahl wrote:
>>>I'm trying to map a U value along a NURBS spline.
>>>Imagine a spline that has 4 points:
>>>Now all I need is the uv's to reflect the distance
>>>between these points so that the u value would be:
>>>This could obviously be done by merely mapping $TY to $MAPU.
>>>However, now imagine a nurbs curve that twists and turns -
>>>I need the u value to reflect the length along the curve
>>>to any given point (the arc-length or chord-length).
>>>Hope someone has an answer ...
>>>Thanks for your time,
>>>PS Maya does this automatically :)
>>Yup - but unlike Maya, Houdini gives you a choice ;)
>>Get a UV Texture Sop and set it to Texture Type: Arc Length Spline
>>and Apply To: Point Texture
>>If you want your UVs to be between 0 and 1 then first you'll need
>> Origin = 0
>> Length = 1
>>You'll only get the exact result you ask for above if your nurbs is
>>Sidefx-houdini-list mailing list
>>Sidefx-houdini-list at sidefx.com
>Sidefx-houdini-list mailing list
>Sidefx-houdini-list at sidefx.com
More information about the Sidefx-houdini-list