Post Processing: Use the pmdrs postprocessing library in examples

[AxiomeCG]

Description

I'm answering the call of @mrdoob on Twitter !

We'd like to update the old examples on postprocessing using the library https://github.com/pmndrs/postprocessing

Solution

I began to work on the first example I've seen:

It is using the postprocessing library from pmdrs.

Alternatives

I'm not sure alternatives apply here.

Additional context

No response

[mrdoob]

Thanks for working on this! 🙏

Hmm... If we look at #26160 we can see that there are cases when having a composer code in this repo is handy. That PR would have been harder to do if it required modifying an external library.

Your progress in #26247 is very useful to see how we could align both composers more as well as the issues people struggle with. However, I wouldn't worry about trying to replace all the examples as there's still value to have both.

Maybe eventually we could end up in a more unified API and make https://github.com/pmndrs/postprocessing the repo for passes/effects?

[CodyJasonBennett]

#26160 notably contains fixes for three.js core, but with them you can do the same in user-land like I do in https://codesandbox.io/s/kgjxfb. The fix is the same, but I'm not going to PR it anywhere without movement there.

I'm not sure about aligning the APIs with pmndrs/postprocessing#419 ahead for its next milestone. It's quite transformative, but maybe that's opportune for optimizing these effects and their resource dependencies. It moves to a pipeline-based rendering approach, although I don't believe it's informed about the existence of node materials. I believe this was briefly mentioned in #26071 which made HalfFloatType the default FBO precision and discussed SRGB8/FP16 presets.