[Sidefx-houdini-list] About shaders

Jordi Bares jordibares at the-mill.com
Sun Sep 30 16:28:03 EDT 2007


Thanks, will put my head on that tomorrow.

:)

jb


On 30/9/07 17:33, "guillaume laforge" <guillaume.laforge.3d at gmail.com>
wrote:

>> PS. About the translucency, I imagine I will have to jump to VOPS.
> 
> Yes.
> 
> Create a vop surface shader.
> In this new vop add a Global Variable node. Negate N with a ... negate node.
> Add a lighting model node. Choose Lambertian model. Plug the negate node in
> the "nN" input.
> It gives you a basic translucency shader.
> 
> Cheers
> 
> Guillaume.
> 
> On 9/30/07, Jordi Bares <jordibares at the-mill.com> wrote:
>> 
>> I guess my next step as soon as I finish the project I am in is to go to
>> our
>> code and convert it.
>> 
>> I feel SideFX should address those things that are so important for people
>> moving away from other tools to start running in a production environment
>> as
>> fast as possible.
>> 
>> Thanks,
>> Jb
>> PS. About the translucency, I imagine I will have to jump to VOPS.
>> 
>> 
>> On 30/9/07 14:41, "guillaume laforge" <guillaume.laforge.3d at gmail.com>
>> wrote:
>> 
>>> Hi Jordi,
>>> 
>>> I agree, a monolithic shader a la Mental Ray mia shader could be very
>> handy.
>>> 
>>> 
>>> Translucency effect looks like a good training with vops :-). I think
>> you
>>> need to use a negative normal vector for the dot product with the light
>>> vector.
>>> 
>>> In vop, you can use a Lambertian lighting model and plug a negative
>> normal
>>> vector in the nN input.
>>> If you need some transparency, it can be useful to mix the translucency
>>> factor with the transparency factor
>>> like in the mia shader ( if translucency factor set to 1, transparency
>> is
>>> null ).
>>> 
>>> Since I started to use Houdini, I think about building a monolithic vop
>>> surface shader network too. If there is something like that on the web,
>> I'm
>>> interested too.
>>> 
>>> Cheers
>>> 
>>> Guillaume Laforge | La Maison
>>> 
>>> 
>>> 
>>> On 9/30/07, Jordi Bares <jordibares at the-mill.com> wrote:
>>>> 
>>>> I am using H8.1 for the project I am working, and specially on the
>> shader
>>>> area I feel a bit weird, specially because doesn't seem to have a
>>>> monolithic
>>>> general purpose shader that can cope with everydays' basic stuff.
>>>> 
>>>> I am using VEX Layered surface I was expecting to have other tools also
>>>> like
>>>> simple translucency, incandescence...
>>>> 
>>>> Is there anything I have missed? Would you recommend me to use another
>> vex
>>>> shader for the translucency? If so, which one, doesn't seem to be one.
>>>> 
>>>> On another note, may be a community OTL that has wrapped this?
>>>> 
>>>> Just as suggestion, here at The Mill we use all the time a monolithic
>> and
>>>> very optimized supershader that does all sorts of things, from blurry
>>>> reflections, thin film, incandescence, transparency tricks, multiple
>> mixed
>>>> specular calculations (blinn, phong, etc..) plus we have setup a bunch
>> of
>>>> presets that do the job 95% of the cases with minor tweaks, probably
>> one
>>>> of
>>>> the most productive tools we have.
>>>> 
>>>> Any chance the Houdini community has developed something similar to
>> share?
>>>> 
>>>> 
>>>> In any case, I would like to ask specially about the translucency
>> effect,
>>>> anyone could point me in the right direction?
>>>> 
>>>> 
>>>> Thanks in advance
>>>> jb
>>>> 
>>>> 
>>>> _______________________________________________
>>>> Sidefx-houdini-list mailing list
>>>> Sidefx-houdini-list at sidefx.com
>>>> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>>>> 
>>> 
>>> 
>>> 
>>> --
>>> Guillaume Laforge
>>> _______________________________________________
>>> 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
>> 
> 
> 
> 
> --
> Guillaume Laforge
> _______________________________________________
> 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