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/showthread.php?82484-VRayVolumeGrid-fumeFX&highlight=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
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.
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.
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?
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.
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.
Alright, caught it - thanks very much! The fix will be in the next nightlies and for the next V-Ray patch/service pack as well.
Until then, the only workaround I could find is to make sure the points on the curves and on the color gradients are created sequentially from left to right and are not rearranged later - you can move the points around, but they should not swap places and a new point should not be created between two other points - only to the right side of them. Basically, the curves and gradients will not work if the points are not sorted by their X coordinates in increasing order. I guess a mel or python script could be created that would sort the attributes after a change is made. Please let me know if you need help with it.
Thanks Svetlin,
I will give a try on that and see how it goes.
I have a doubt though, i used the existing curve on volume grid and keep adding the points or remove the points all together and start fresh.
But i still get a black render
