Cycling 74 » Topic: Understanding how nurbs work http://cycling74.com/forums/topic/understanding-how-nurbs-work/feed Thu, 20 Jun 2013 02:10:19 +0000 http://bbpress.org/?v=2.2.4 http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-51389 <![CDATA[Understanding how nurbs work]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-51389 Fri, 16 Jul 2010 19:24:09 +0000 Garrett Hi

Trying to understand how nurbs work. I’m using Andrew Bensons patchs manipulator and catchnurbs but catchnurbs is getting me closer to what I want. I’ve swapped out the sound for video to control the nurbs but something I can’t figure out is how Andrews original seems to grow from the centre of the jit.window and mine is always right, above and forward of this. Mine is how I would expect it to work but how is Andrews being corrected? How would I offset mine to correct it? Thanks in advance

Garrett

– Pasted Max Patch, click to expand. –
]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184252 <![CDATA[Re: Understanding how nurbs work]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184252 Fri, 16 Jul 2010 20:15:04 +0000 Luke Woodbury Don’t know about Andrew’s but you can use the ‘position’ attribute on nurbs, as well as rotate and scale etc. Its in the nurbs help file.

]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184253 <![CDATA[Re: Understanding how nurbs work]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184253 Fri, 16 Jul 2010 23:50:46 +0000 seejayjames as well as the position/scale/rotation attributes on the entire scene, send them to jit.gl.render. There’s “camera X Y Z” as well, where (I believe) 0. 0. 4. is the default. Sending these commands will keep the whole scene in proportion, helpful when you’ve got multiple nurbs going :)

]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184254 <![CDATA[Re: Understanding how nurbs work]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184254 Sat, 17 Jul 2010 11:01:45 +0000 Garrett hi both

Yes I started playing with position shortly after, I did think of using the equivalent of glortho and remapping the coordinates from 0 to 1 instead of -1 to 1 (if I could find what the equivalent is for jit.gl.render) but I was wondering if there was a way of correcting this within the matrix itself? Is there a way to apply a formula to all the cells matrix? Something like (a x 2) – 1 would correct this but I don’t know how to apply it.

Garrett

]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184255 <![CDATA[Re: Understanding how nurbs work]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184255 Sat, 17 Jul 2010 12:55:50 +0000 seejayjames jit.expr can do pretty much everything you need for matrix math:

jit.expr @op * @val 2.
|
jit.expr @op – @val 1.

etc…

]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184256 <![CDATA[Re: Understanding how nurbs work]]> http://cycling74.com/forums/topic/understanding-how-nurbs-work/#post-184256 Sat, 17 Jul 2010 13:54:48 +0000 Garrett ah good I was starting to look at the right thing but getting bit confused with jit.dimmap. Thanks.

Garrett

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