View Full Version : Colouring a wall with Houdini

02 February 2005, 11:22 AM
Hi everyone,

I am trying to create an old kitchen using houdini, and am having difficulty creating the dirty/burnt effect on the wall above and behind the grill/cooker. The grill is basically like a BBQ, and so would through up loads of smoke and soot onto the wall directly behind it, and on the ceiling above it, how do i go about creating this colouring so that it looks realistic? I would really appreciate any help with this, as i am still quite new to houdini...



02 February 2005, 07:10 AM
I'm no shader writer so I can't really say. But this isn't really a Houdini-specific question per se. It's more about how does one write a shader (a prman one would be comparable). Try the shading writing forums? cgtalk even has one for it (Texturing and Surfacing). Unless all you're asking is how to put up a texture map. :)

02 February 2005, 08:22 AM
Hi there,

For the quickest way in terms of VOPs, you could I'd try the following..

*/ Create a VEX Suface Shader VOPnet.
*/ Wire a Shiny Metal VOP into the Cf channel of a Mold VOP. The resultant "color" of the Mold VOP goes into the Output Cf. There will be some noise frequency tweaking to get the mold noise into the appropriate scale for your scene.
*/ Apply this shader to your geometry.

For my quick little test, I used one of the HDR maps from Debevec's HDR collection - in particular, the kitchen scene.

Check the screen grab for some hints...

Good luck,

PS. Don't use the Rust VOP - it's a little broken. Its meant to automatically layer on top of your material like the Mold VOP but it doesn't.

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