View Full Version : Volumetric Light as a crackling ball of energy-- how to?

04-16-2016, 06:12 PM
I'm attempting to use a volumetric light as a "crackling ball of energy" that periodically travels between two objects, rather like the energy balls in the game Portal.

Getting the effect to terminate in a rather sharp demarcation is the problem, can't seem to get a semi-hard edge on the light.

Is this the right approach (volumetric light), or am I barking up the wrong tree?

ASIDE: I thought there were more presets for Vol. lites than I see in 2015.3. :(

04-18-2016, 05:11 PM
It may not be what you're after, but I've had a bit of luck using a highly jittered subpatch object with a lot of moving displacement map textures (Turbulence and Ripples2) combined with the Fast Fresnel shader using a high Minimum Glancing Angle so only the edges show up. The Edge Transparency set to Opaque with a small (e.g. .1) value works as well. Attached is a sample scene. The key technique is having the displacement map layers move in Position and Rotation. Speeding up the associated envelopes makes it more frenetic.

As I said, it may not be what you're after, but kind of a cool effect anyway. In this particular scene, I used a tesselated sphere jittered, subdivided, jittered again and subpatched. The Bloom Image Filter adds "glow" at points where the luminosity channel rises above Bloom's threshold. The still doesn't due justice to the motion of the displacement textures making it come "alive".


I've also used the same technique to have "energy flow" along a path using bones and an appropriately shaped jittered, displaced convoluted object. For example, the "electrical impulses" along this simple robotic arm move with the arm, and the displacement maps are adjust to have the energy flow up the arm.



P.S. I noticed after I rendered the sequence that the Bloom image filter "maxed out" along the way. I'd try to adjust the Bloom threshold down to avoid that.

04-18-2016, 06:33 PM
Thanks for the example-- can always use a new technique, that's very interesting.

I managed to get something going that was good enough for a hobby project, ie no art director, by cranking up the Volumetric light's Luminosity and Density to 1000% both. That gave a good edge to the 'ball', less and it was too soft.

One interesting thing: I decided to add another volumetric "inside" the main one, for some texture, and that didn't work at all: I didn't pursue it, but it actually seemed to subtract any luminous volumetric effect away from the first light, against my expectations. Dangit.

Here's the settings I wound up using:
And the [email protected] look itself:

I like your effect better, looks more crackly. :thumbsup: