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Working with Liquids in Glass

Posted: Tue Mar 26, 2013 11:02 pm
by gordonrobb
Been trying to work out how to get liquid inside glass to look good.

First thing I sussed was Direct Light didn't work. So Path or PMC it is then.

I modelled a simple glass with a liquid object inside. I did 3. Left one has the liquid object bigger than the inside (intersecting the bottle), middle one is exactly the same size, right one is slightly smaller.

I have a couple of questions though. Firstly, how they look in Standalone. You can see that they all look different. I have used a clear glass and whisky material from Live DB. Secondly, in Lightwave, trying to emulate the LiveDB surfaces, the left one (intersecting) is darker.

My question is, from the developers, how am I supposed to model this. Which version is the right version?

Re: Working with Liquids in Glass

Posted: Wed Mar 27, 2013 1:36 am
by badmilk69

Re: Working with Liquids in Glass

Posted: Wed Mar 27, 2013 8:09 am
by gordonrobb
Badmilk, any reason you've directed me to a thread that, up until I asked the question hadn't been updated in over a year? That thread discusses the exact question I've just asked, but does not answer it. I just want to know what's the best modelling/texturing solution for getting it to look/behave right - and if standalone is different from LW Plugin.

Re: Working with Liquids in Glass

Posted: Wed Mar 27, 2013 10:38 am
by gordonrobb
Have solved the colour variation. It was modelling error. Would still like to know which modelling method OTOY recommend we use.

Re: Working with Liquids in Glass

Posted: Wed Mar 27, 2013 2:19 pm
by ROUBAL
Good question !

Re: Working with Liquids in Glass

Posted: Wed Mar 27, 2013 8:44 pm
by roeland
Most of the information in the linked thread has gone obsolete, we changed the handling of intersecting volumes in 1.11. You should create a small overlap between the glass and the liquid.

DirectLighting will work, but you probably need to increase the specular depth setting. It is by default too low to render this kind of objects (it needs at least 7).

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Roeland

Re: Working with Liquids in Glass

Posted: Wed Mar 27, 2013 9:24 pm
by bicket
roeland wrote:Most of the information in the linked thread has gone obsolete, we changed the handling of intersecting volumes in 1.11. You should create a small overlap between the glass and the liquid.

DirectLighting will work, but you probably need to increase the specular depth setting. It is by default too low to render this kind of objects (it needs at least 7).

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Roeland
Thanks I try and it work pretty well with PT and PMC (for scattering)

Re: Working with Liquids in Glass

Posted: Wed Mar 27, 2013 10:09 pm
by gordonrobb
roeland wrote:Most of the information in the linked thread has gone obsolete, we changed the handling of intersecting volumes in 1.11. You should create a small overlap between the glass and the liquid.

DirectLighting will work, but you probably need to increase the specular depth setting. It is by default too low to render this kind of objects (it needs at least 7).

--
Roeland
Cool, thanks. DL works in terms of the surfacing, but the absence of Caustics ruins it.

thanks for the info though.

Re: Working with Liquids in Glass

Posted: Thu Mar 28, 2013 8:37 pm
by dwr08
I'm not sure if it will work the same in Octane (haven't had a chance to fully test it), but for Maxwell and other PT engines, the trick was as described here: http://novedge.typepad.com/.a/6a00d8345 ... 970d-800wi.

Re: Working with Liquids in Glass

Posted: Fri Mar 29, 2013 12:17 am
by gordonrobb
dwr08 wrote:I'm not sure if it will work the same in Octane (haven't had a chance to fully test it), but for Maxwell and other PT engines, the trick was as described here: http://novedge.typepad.com/.a/6a00d8345 ... 970d-800wi.
But that's not how Roeland describes to do it, and I'm taking his advice as someone that knows. Should I not be?