Advanced displacement techniques for materials in Houdini

[PatriciaCornet]

Hi everyone!

Following the success of our GridMarkets Featured Houdini Artist profiles, we are excited to introduce our new series of Featured Animation Schools. The focus of our first feature is CG Spectrum Film and Game School, based in Melbourne, Australia.

We'll get the opportunity to learn some advanced displacement techniques for materials from CG Spectrum’s Houdini instructor, Ben Fox, who kindly shares one of his video tutorials with us.

http://www.gridmarkets.com/cgspectrum.html

Let us know what you think,

Patricia and the rest of the GridMarkets team

 

Edited September 23, 2016 by PatriciaCornet

[kev2]

Hi, 

Could you guys can make the example file available? I went through the video and notes a couple times but am missing something as the displacement isn't showing up at render time. Nice technique, I'd like to sort out where I've gone off track. Thanks, Kevin

[Netvudu]

Hi Kev,

where did you go off track...can you get colored areas to show where the displacement will be applied?

 

EDIT: Here you go. This is something I just did in a hurry. The shader ain´t exactly the way they explained, but it´s pretty similar.

I had to invert the SDF values at shading time to get something useable. Also I ended up creating the SDF with VDB as opposed to the Iso Offset the tutorial uses. VDB is way faster for heavy geometry, so it´s better this way.

I locked the geometry and referenced the node from the shader so you don´t need to cache any geometry at all which is another nice bonus.

Something funky happened to my license while I was working, and it seems you need an apprentice to open the scene properly. Sorry for that.

Finally, it´s a bit unorganised, but I quickly put this down for you. Hope it helps.

RBDFractureDisplacement_v001.hiplc

Edited September 25, 2016 by Netvudu

[kev2]

Thanks Netvudu - Haven't gotten back to the desk again but before I left, I had tracked my problems to the SDF. I'll try inverting and see if that gets it going. I'll reply tmr, thanks for the file. 

 

[kev2]

Thanks Netvudu. Your file works fine but I still haven't been able to get the shader to pick up the volume sample. I tried both Isooffset and VDB SDFs but no luck. I thought it might be the SDF file I/O but it didn't work when I tried a file path with op:pathtosdf either. Not sure where to go now. Here's my file if you have a chance to take a look. 

 

   

DisplacementAtRenderFractureObj.hipnc