(I can’t make any apologies for the crappy Photobucket video hosting, as I have yet to sign up with Vimeo. I feel I have no business doing so until I’m putting out steady work.)
This is just a simple test to see how this effect would look. Actually, I think it looks quite good, and wouldn’t mind using it in any animation calling for such an effect. However, the displacement by nature causes the flash to be far off-center from where it should be. I tried some experiments with Translate nodes, but no luck. I’m not even sure if that can be fixed.
Uses: Billboard particles with Halo blend textures set to UV, plus Noise, both affecting alpha and fading from white to black to imitate fading. Displacement node uses standard Clouds (hard noise) with an X/Y displacement of 60 each. Uses RGB Levels node for color. Finished flash mixed with skydome background using Screen.
And a still of the same effect with some different settings:
Now, I’ve done some tests with this, and I have not yet found any effective way of making the Clouds “swirl” like I want them to (increasing Z values). The only input node that seems to achieve something like this is Time, but when connected to the Texture node’s Offset and Scale, it only affects the X offset and the Y scale, and I don’t know why. If I could sort that out, the effect would become even more flexible.
Well, let’s see. I started out with an object with a single vertex. I gave this a particle system using Billboards. I gave the object a UV map but made no adjustments to it. I gave this object a material with a Blend texture (halo), set the Alpha to 0 and then allowed the texture to affect Alpha. I also enabled Z-Transparency to allow the Billboard-Halos to “glow” over one another. I then set the particle system to spray out about a hundred of these in random directions.
For the main background, I used a skydome made up of a 32x32 UV sphere with a crummy night-sky texture I’d made in GIMP a while back.
For the displacement itself, I place the particles on Layer 2 (where the background is solid black, very important) and the skydome on Layer 1. Then, to put things where they go, I use a Mix node and Add the particles layer over the sky layer. To mix things up, I use another Mix node and a Blur node. I take the particles layer, then Add it to a blurred copy of itself (this is simple to do; you just have one input node connected to more than one modifying node). This gives it a nice glow effect.
Now, I take the blurred/added image and run it into a Displacement node. To the Vector plug I connect a Texture node with a Clouds texture. This produces the actual displacement. I turned up the X/Y values to 60 to make it rather pronounced. I’m using Clouds with Hard Noise as this produces plenty of garbling without being too excessive (using a complex Marble texture can make some weird stuff, too). One could theoretically use Cellnoise to make a kind of digital data-packets effect, or Stucci for some strange oily swirls.
That’s about it. The image linked above of the compositor should explain the rest. The positioning problem can be solved crudely by simply moving the particle object itself further down and left to compensate for how much it gets moved up and right during the displacement step.
