View Full Version : volumetric fading per distance to object- How to?

09-24-2018, 08:17 AM
Maybe a stupid question and the solution is just at hand - but I don't see it:
How can I achive the same fading effect with the new (LW 2018) volumetric-system as with the old HyperVoxel-system?
I want to fade the smoke coming out of a volcano by the distance of the particle to the null that is at the hight of the volcano. So the smoke gets thinner the higher it goes till it disappears. This worked fine with the legacy-HyperVoxels by using a gradient applied to the thickness or the dissolve. I tried it with a gradient-node but it doesn't give me the 'distance to object' option.
I would use the legacy HyperVoxels but I want to use some new volumetrics clouds and I can't use the old volumentric and the now one at the same time! (rendering options)

But does anybody know how to apply this fading-effect with the new volumentric-particles? Thank you!

09-24-2018, 11:13 AM
Not sure why you would use distant to null, when a particle emitter ..emitts from the origin of an emitter, particle gradient should be enough, but I think you should use item info and distance nodes.
You may also try to add a color or scalar layer, which allows you to add distance to object gradients,then feed that in to texture density.


09-24-2018, 11:17 AM
Old school scalar gradients, distance to null...


And..beware, use color not alpha output to the input of texture density.

09-25-2018, 08:00 AM
Oh thank you, prometheus!

That did it, now I remember that I used it before!
Haven't worked with LW 2018 for a long time. I only remembered the 'old' way without nodes.
Here's my result - I used the Particle Age and also used it for the radius. But why I must plug in the color is not clear to me, but you are right: it doesn't work with the alpha.


Thank you!