[Sidefx-houdini-list] moire patterns

zhang xiao zhangxiao6776 at gmail.com
Sat Nov 4 05:53:26 EST 2006


Hi, Zoran:
     There is one chapter on the Advanced Renderman book which talking about
LOD and procedural primitives,
it's pretty clear. Geometry based LOD requires different resolution of your
model, and carefully choosen
of the detail range for each model, the render will take care of the
interpolation part for you. In terms of
shader based LOD only, I'm afraid you have to do some trick like simon
mentioned, you can also give a try
to geometry LOD, do some quick test, maybe also works in your case, as a
matter of fact, if you didn't change
the geometry resolution , only change the texture, it's the same as Simon's
trick basicly.
xiao



On 11/4/06, zoran arizanovic <zoran.arizanovic at gmail.com> wrote:
>
> hi zhang
> I am doing this in renderman shader
> do you know more how lod in rm works on shader basis?
> thanks
> Zoran
>
> On 11/4/06, zhang xiao <zhangxiao6776 at gmail.com> wrote:
> >
> > like renderman, mantra is also micropolygon render, and i believe it
> > has silimar
> > LOD functionality as in renderman.
> > xiao
> >
> >
> > On 11/4/06, zoran arizanovic <zoran.arizanovic at gmail.com> wrote:
> > >
> > > thanks for answers
> > > yes this is what I was thinking like some kind of level of detail
> > > approximation for near and far frequency of threads
> > > zoran
> > >
> > > On 11/3/06, Simon Barrick <simon at primalpictures.com> wrote:
> > > >
> > > >
> > > > You can do frequency clamping too, which is easier than analytical
> > > > anti-aliasing. You can use the area function to determine how close
> to
> > > the
> > > > texture you are and then as you approach the aliasing threshold you
> > > blend
> > > > into an "averaged" version of your texture. Works pretty well.
> > > >
> > > >
> > > > -----Original Message-----
> > > > From: sidefx-houdini-list-bounces at sidefx.com on behalf of Andrew D
> > Lyons
> > > > Sent: Fri 03/11/2006 19:14
> > > > To: sidefx-houdini-list at sidefx.com
> > > > Subject: Re: [Sidefx-houdini-list] moire patterns
> > > >
> > > > Procedural patters alias unless you can put some anti-aliasing code
> in
> > > > your shader. The "Advanced Renderman" book has a chapter on that.
> The
> > > > easiest alternative is to use .rat textures instead of procedural
> > > > pattterns.
> > > >
> > > > Cheers
> > > >
> > > >
> > > > On 03/11/06, zoran arizanovic <zoran.arizanovic at gmail.com> wrote:
> > > > > hi
> > > > > I am trying to do procedural cloth shader for huge baloon
> > > > > the problem i have is that close up is ok i see threads but from
> far
> > I
> > > > get
> > > > > moire patern type noise
> > > > > is there any  way to avoid this , or waht would be strategy for
> > doing
> > > > this
> > > > > two different setups for close and far?
> > > > >
> > > > >
> > > > > --
> > > > > Zoran Arizanovic
> > > > > http://arizanovic.blogspot.com/
> > > > > _______________________________________________
> > > > > Sidefx-houdini-list mailing list
> > > > > Sidefx-houdini-list at sidefx.com
> > > > > https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
> > > > >
> > > >
> > > >
> > > > --
> > > >
> > > > =======================================
> > > > Andrew D Lyons | Digital Artist | http://www.tstex.com
> > > > =======================================
> > > > _______________________________________________
> > > > Sidefx-houdini-list mailing list
> > > > Sidefx-houdini-list at sidefx.com
> > > > https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
> > > >
> > > >
> ______________________________________________________________________
> > > > This email has been scanned for Primal Pictures by the MessageLabs
> > Email
> > > > Security System.
> > > >
> ______________________________________________________________________
> > > >
> > > >
> > > >
> ______________________________________________________________________
> > > > This email has been scanned for Primal Pictures by the MessageLabs
> > Email
> > > > Security System.
> > > >
> ______________________________________________________________________
> > > >
> > > > _______________________________________________
> > > > Sidefx-houdini-list mailing list
> > > > Sidefx-houdini-list at sidefx.com
> > > > https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
> > > >
> > > >
> > > >
> > >
> > >
> > > --
> > > Zoran Arizanovic
> > > http://arizanovic.blogspot.com/
> > > _______________________________________________
> > > Sidefx-houdini-list mailing list
> > > Sidefx-houdini-list at sidefx.com
> > > https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
> > >
> >
> >
> >
> > --
> > http://www.youtube.com/watch?v=sLqTRB6erEQ
> > http://youtube.com/watch?v=OCHmFU1aU5E&search=hai%20mera%20dil
> > http://www.youtube.com/watch?v=hY66xoj7Y50
> > http://youtube.com/watch?v=-_2gW3zwMMQ
> > _______________________________________________
> > Sidefx-houdini-list mailing list
> > Sidefx-houdini-list at sidefx.com
> > https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
> >
>
>
>
> --
> Zoran Arizanovic
> http://arizanovic.blogspot.com/
> _______________________________________________
> Sidefx-houdini-list mailing list
> Sidefx-houdini-list at sidefx.com
> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>



-- 
http://www.youtube.com/watch?v=sLqTRB6erEQ
http://youtube.com/watch?v=OCHmFU1aU5E&search=hai%20mera%20dil
http://www.youtube.com/watch?v=hY66xoj7Y50
http://youtube.com/watch?v=-_2gW3zwMMQ



More information about the Sidefx-houdini-list mailing list