Convolution Bloom (FFT) or Bloom with custom flares textures

[kitaedesigns]

Would it be possible to implement a version of Bloom with either a Convolution Kernel or with an option for custom flare textures? Looking to create an effect similar to the new PostProcessing Anamorphic Demo to simulate Bloom in real-world lenses better. This in combination with the new Lens Distortion, Lens Flare, and Noise would look amazing.

Anamorphic Demo
https://threejs.org/examples/?q=anam#webgpu_postprocessing_anamorphic

Convolution Bloom
https://docs.unrealengine.com/5.0/en-US/bloom-in-unreal-engine/

[vanruesc]

I'm planning on implementing the glare effect described in https://www.froyok.fr/blog/2021-09-ue4-custom-lens-flare. There's a ticket for LensFlareEffect (#581) which could also implement that aspect. I'll add the anamorphic example to the list of references in that ticket.

Convolution Bloom from UE is not really suited for realtime rendering, so I don't see much benefit in adding it at this time. Quoting from the docs:

Bloom Convolution is designed for use with with in-game or offline cinematics or on high-end hardware, while the Standard bloom should be used for most game applications.

In other words: anamorphic bloom/glare is already planned, but the approach will likely be different compared to three/UE.

[kitaedesigns]

Gotcha, that all makes sense. I can probably provide you with some Flare textures for testing as well.

There's also this repo from Anderson Mancini for Lens Flares that doesn't use PostProcessing in case it's of interest.
https://github.com/ektogamat/lensflare-threejs-vanilla

[vanruesc]

Closing in favor of #581.