VolumeGrid and FumeFx 4

[CCX]

Hi
I am using vray 3.40.02 and fume fx 4.
I cached a fume simulation in vdb format and imported the cache into volume grid.
However I am having a tough time to match the look from fume to vray volume grid. especially in
the Fire Curve.
I followed this parameters note from Svetlin.
http://forums.chaosgroup.com/showthr...ght=volumegrid

But when i change the default Fire luminance curve to match fume's fire ramp, it renders completely black.
Could someone help me where I might be going wrong.
Thanks

[georgi.zhekov]

Hello,

Can you post a screenshot of your settings or if you can send a scene with a single cache file that would be great.

Thank you

[CCX]

Hi

Sure,
I have uploaded the scene along with a single cache file and the settings.

https://drive.google.com/folderview?...Gc&usp=sharing

This is the Fume gradient


and render


and the matching VolumeGrid gradients.


Vray rendered black, so I didnt attach any image for that.

[CCX]

Hi
After tweaking a little bit. I seem to have got closer to fume render.
Here is the render from vray volumegrid.


after importing the cache into volumegrid, and accepting the render preset for fume fx.
I matched only the color gradient of vray grid to fume's. but kept the default opacity curve unchanged.
Instead, I reduced the opacity multiplier to 0.01 and increased the luminance scale to 1.
Also I didnt render smoke in fume, i disabled the smoke here too.
The current render is similar to the fume render, bar the intensities.
I will tweak more on it and see where it goes.

[Svetlin.Nikolov]

Sorry for the late reply! Looking good - we will update the Mayan Volume Grid soon with the new Phoenix/VolumeGrid ramps and gradients and will equalize the render options with the 3ds Max volume grid, so I hope it would be easier to use this way. If there's anything we can help with, please do ask.

Cheers!

[CCX]

Thanks for the info Svetlin.
That should work good. Will there be an update on the nightlies sometime ?

[cfuji]

Hi!

We are having the same issue here. We change the Fire luminance curve and it renders complety black. Is there any workaround for it? Or any fix in the nightlies?

We are using vray 3.40.02 and fume fx 4 too.

Thanks!

[Svetlin.Nikolov]

Hey,

Could you share a shot with your render settings? Was it completely black before you edited the curve?

Cheers!

[cfuji]

If we don't add any point the render is not black. Yes, I think we can share the setting when I have them I will post here.

[CCX]

From what i have noticed, It will work only if we leave the opacity curve for fuel at default in Volume grid.
Any minor tweaking on the curve renders black, which makes Fume's opacity curve, void in a way.

[Svetlin.Nikolov]

Wow, do you have a scene with the broken curve? Would it be possible to send the scene over to Support?

Cheers!

[CCX]

Oh Hey Svetlin,
well Pretty much for any fume sim, when I am using volume grid to render, I am not using the Opacity curve, because it ends up rendering black. Sure I can send one, the first thing in the morning tomorrow.

[cfuji]

We can render with the following configuration, but if we add some point in the Fire Luminance, it renders all black.


Because of the limitation of the Fire Luminance curve, we can not get the Fumefx look:

https://drive.google.com/open?id=0B-...HRFbjRZX2RldUk

[Svetlin.Nikolov]

Would it be possible to also share a shot of how the settings look when it renders black?

Thanks very much!

[cfuji]

Just adding a point in the curve (red circle), the render is all black.