ReSTIR FG integration in RTX Remix

[gilded wagon]

Inspired by this new algorithm to simulate global illumination + light caustics in real time. Pretty cool

https://youtu.be/7esNRZSQxQA

Currently there's no code available so will have to wait for that

[neon merlin]

There is?
https://github.com/TU-Clausthal-Rendering/ReSTIR-FG/tree/aa19da4e51625c25497b1f63ad128cb32d813945/Source/RenderPasses/ReSTIR_FG

[gilded wagon]

Umm aren't those the files required to build the demo?

[neon merlin]

Yea, so it's the code?

[gilded wagon]

idk, will have to figure out how the hell can this be added to remix

[neon merlin]

here is the shaders

[gilded wagon]

Do you know where rtx remix stores it's ReSTIR GI files, was only able to find link to RTXDI remix branch

[neon merlin]

Using, https://www.voidtools.com Everything:

\src\dxvk\rtx_render\rtx_restir_gi_rayquery.h
\src\dxvk\rtx_render\rtx_restir_gi_rayquery.cpp
\src\dxvk\shaders\rtx\pass\rtxdi\restir_gi_reuse_binding_indices.h
\src\dxvk\shaders\rtx\pass\rtxdi\restir_gi_final_shading_binding_indices.h
\src\dxvk\shaders\rtx\pass\rtxdi\restir_gi_final_shading.comp.slang
\src\dxvk\shaders\rtx\pass\rtxdi\restir_gi_spatial_reuse.comp.slang
\src\dxvk\shaders\rtx\pass\rtxdi\restir_gi_temporal_reuse.comp.slang

[gilded wagon]

Interesting

moment

[hushed patio]

So just as a note - AFAICT ReSTIR FG is an algorithm with a sample implementation, not a library intended for distribution. I doubt their shaders are directly portable, someone will basically have to re-implement the algorithm in Remix's shaders. We do at least use the same shading language as Falkor, but last I checked they have a ton of utilities and abstraction layers in Falkor's shaders (as they're intended for quick experiments). Whereas Remix's shaders are more bare metal (focused more on size and speed instead of ease-of-coding)

[charred galleon]

so it's possible to implement restir fg into remix, am i right?

[gilded wagon]

If you're skilled enough it is, although as Mark said you need to implement it as a shader like how ReSTIR GI works

[charred galleon]

@hushed patio will you add this to the remix?

[charred galleon]

or not?

[hushed patio]

I'm unaware of any plans to integrate this right now - we're pretty busy with a bunch of other things at the moment

[charred galleon]

ok, but can i know, will be there updates for restir or caches? or something else?

[hushed patio]

I know there's still research going on for improving restir within Nvidia, and at some point we will probably integrate a newer more advanced version into Remix. No clue exactly which technique that would be, or when it will happen.

[gilded wagon]

From the looks of it, modifying or replacing ReSTIR GI from remix seems like a challenging task for an average person that has laymen knowledge about code implementation and such

[hushed patio]

well, implementing cutting edge algorithms into a cutting edge renderer is kinda a specialist task.

could be a good project for a grad student in a computer graphics program or something - the writer of that paper implemented it into Falkor, which is only a bit easier to work with than Remix when it comes to this sort of thing.

[charred galleon]

Will there be any caustics in the remix at all? well, in the near future

[hushed patio]

#general-remix message

[charred galleon]

oh, sorry 😭

[hushed patio]

that was meant as a link to a specific post in general, not a prompt to repost the question there. sorry for the confusion

[native rune]

@alpine summit

[alpine summit]

Oh wow

God caustics are so cool

[charred galleon]

that would be cool to have these caustics in remix (like chess titans)

[charred galleon]

damn, no news in that thread (

[sleek hornet]

been half a year, anything new?

[charred galleon]

just new nrd and thats all

[sleek hornet]

Can u send a link to the Nrd?

[charred galleon]

https://github.com/NVIDIA-RTX/NRD

[limber veldt]

given that we have NRC now, i don't think we need ReSTIR FG?

[native rune]

caustics

also

i think that they might work together?

[limber veldt]

they seem to, yes. but NRC was designed around using the original ReSTIR as the base, so i don't think FG would even work with it

[charred galleon]

restir and nrc work separately in the remix, right?

[limber veldt]

in the paper, NRC seems to work on top of ReSTIR

i could be misreading it

[charred galleon]

cuz in remix they are separated indirect lighting modes

[limber veldt]

yeah, it's probably just the way it's being selected

definitely take a look at the paper

all of the verbiage seems like it's running on top of ReSTIR to me

[limber veldt]

so #general-remix message