Rainbow glow effects

Hi guys, how is it possible to achieve a rainbow-like neon effect on a circle mesh?
Screenshot 2022-12-05 at 17.28.46
(like payoneer logo, but with glowing)

I believe it is only possible with shaders, but now really sure how to make it

Something like this?

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Yeap, exactly! How have you achieve it?

With that good old two-composer approach. Modified though.
Here you are: https://codepen.io/prisoner849/pen/jOKXrRz?editors=0010


Paul, you are such a huge lifesaver, thank you a lot!! Going to apply your code to my objects right now :slight_smile:

Paul, I was able to import my model and exclude it from glowing pass applying that shader from cube, but if I change background it is affected by bloom, I am not sure is there a way to apply shader to bg or to exclude it from bloom render pass as well?
Screenshot 2022-12-06 at 23.51.09

Ah, I thought I took background in count. Obviously, I didn’t )
Have a look: Tetrahedra (fat lines, batching, texelFetch)
The first link to codepen.

let bg = {
  on: 0x321632,
  off: 0x000000
let scene = new THREE.Scene();
scene.background = new THREE.Color(bg.off);

. . .
// in the animation loop
  gu.globalBloom.value = 1;
  scene.background.set(bg.off); // make it black
  gu.globalBloom.value = 0;
  scene.background.set(bg.on); // set to the desired value
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