Jump to content
Sign in to follow this  
Lukich

strange texture behavior

Recommended Posts

Hi, there. This must be somrething very basic, but I can't figure it out. Let's say, I have a basic grid, apply a uv project to it and put down a shader sop with some rust shader on it. Works like a charm, maps the image across the whole grid. However, if I go to VOPs, create the shader vop, and plug the Color Map node into the Cf, Houdini renders multiple copies of the image, one per face. Do you know what can it be? Thanks a lot!

Luka

Share this post


Link to post
Share on other sites

Hey Luka

You need to tell the VOPnet to use the uv parameters of your geometry. By default each polygon will map from 0-1 (s,t).

To do this put down a shading layer VOP, append a vector to float VOP and then wire the first output into the 'u' parameter of your colormap VOP and the second into 'v'.

The third one, I'm guessing would be 'w', but even after all this time, I'm still not sure what the w parameter will do :)

Hope this helps

Marc

P.S. If you change your polygon grid to NURBS, then it will assign the texture correctly anyway. This is because the s and t map across the entire NURBS patch by default.

Share this post


Link to post
Share on other sites

Groovy! Thanks a lot, Marc! I have to go with the polygon because my actual geometry (grid's just an example) is very complex and converting it to nurbs would take hours. Thanks again :)

Share this post


Link to post
Share on other sites

One other thing that might be worth noting with regards to NURBS patches and uv coordinates: While it is true that NURBS patches have an inherent set of uv coordinates, it is worth noting that an "explicit" uv attribute is not created, and hence, you will not be able to preview the texture in your viewport.

In order to do that, simply put down a UVTexture SOP, and set the texture type to rows & columns... (note that this actually creates an attribute called uv)

That messed with me for a few hours, so I thought i'd pipe up. :huh:

Cheers,

G

You need to tell the VOPnet to use the uv parameters of your geometry. By default each polygon will map from 0-1 (s,t).

14124[/snapback]

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×