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Cornell McRay T'Racing

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Re: Cornell McRay T'Racing

#31

Post by [deleted] »

vinkelhake wrote: post #20
carl_dr wrote: post #18

Earlier quoted context omitted.

> ML trained on video, applied to gamedev, seems like a matter of time. You could do it right now. Indeed! Photorealistic GTA V using ML : https://www.theverge.com/platform/amp/2021/5/12/22432945/int...

The "photorealism" of that ML demo was vastly overstated. A lot of post processing effects in games are there to (somewhat ironically) emulate defects of cameras: vignetting, chromatic aberration, bloom, flares etc. I think this ML demo got there by effectively emulating a low-res, poorly white balanced, low framerate dash cam. I think those "defects" make people see the image looking more like the output of a real (…

[deleted]

Re: Cornell McRay T'Racing

#32

Post by gibbonsrcool »

daenz wrote: post #30

I'm not sure people appreciate how many hours of "hacks" are going to disappear nearly overnight when real time ray tracing becomes common place. Things as conceptually simple as "soft shadows" have multiple manifestations and implementations, and require dozens of hacks to pull off believably.

Does this harm nvidia? I don’t do graphics programming but I would imagine they have a lot of tech to make shadow and many other hacks run fast. Does ray tracing simplify game rendering even though it would require more FLOPS?

Re: Cornell McRay T'Racing

#33

Post by paavohtl »

gibbonsrcool wrote: post #32
daenz wrote: post #30

I'm not sure people appreciate how many hours of "hacks" are going to disappear nearly overnight when real time ray tracing becomes common place. Things as conceptually simple as "soft shadows" have multiple manifestations and implementations, and require dozens of hacks to pull off believably.

Does this harm nvidia? I don’t do graphics programming but I would imagine they have a lot of tech to make shadow and many other hacks run fast. Does ray tracing simplify game rendering even though it would require more FLOPS?

I'm sure NVidia is fine, as they are the market leader in gaming / workstation hardware accelerated RT.

Re: Cornell McRay T'Racing

#34

Post by berkut »

gibbonsrcool wrote: post #32
daenz wrote: post #30

I'm not sure people appreciate how many hours of "hacks" are going to disappear nearly overnight when real time ray tracing becomes common place. Things as conceptually simple as "soft shadows" have multiple manifestations and implementations, and require dozens of hacks to pull off believably.

Does this harm nvidia? I don’t do graphics programming but I would imagine they have a lot of tech to make shadow and many other hacks run fast. Does ray tracing simplify game rendering even though it would require more FLOPS?

> Does ray tracing simplify game rendering even though it would require more FLOPS?

In theory it will, the VFX/CG industry went through the rasterisation -> raytracing change ~10 years ago, as it simplified things (at least in the pipeline, and in the renderers themselves to some degree). It was slower in terms of compute time than rasterisation, but made up for that by not needing things like irradiance/pointcloud caches, shadow map passes, etc (the removal of which made total iteration time faster), and the fidelity it allowed was quite a bit better (global GI, accurate layered materials traced through the surface, volume SSS, etc, etc).

In terms of renderer complexity, it means that while you have to specialise how you use the rays (ray casting/tracing is really just a visibility query), it means you can use them for camera visibility, reflection, refraction, shadows, environment quite easily in a very similar manner (especially with path tracing), whereas with rasterisation, you need rasterisation for the main tri/quad drawing, then (cascading) shadow maps for shadows, then cube mapping for environment lighting/reflection, and these for rasterisation are very different techniques / algorithms.

Re: Cornell McRay T'Racing

#35

Post by alkonaut »

pixelpoet wrote: post #28
alkonaut wrote: post #15

Earlier quoted context omitted.

Indeed and the first part is the first scene done in any ray tracer: https://en.m.wikipedia.org/wiki/Cornell_box

It's by far not the first scene done in any ray tracer, rather an early test scene for radiosity (diffuse-only global illumination, before path tracing was developed).

Oh I meant “when anyone today writes a toy ray tracer, this is usually the first scene you test with it”

Re: Cornell McRay T'Racing

#36

Post by alkonaut »

sillysaurusx wrote: post #17

The astute among you will notice that the outputs look more or less indistinguishable from modern video games -- which is to say, they don't look real. It's not to downplay the achievement. It's to say that I hope one of you takes up the task of making truly real, indistinguishable-from-TV videos generated in real time. It may seem like an impossible dream. But so was realtime raytracing, at the start of my career. A…

Realism is only one of the benefits of global illumination, the other (perhaps more important) is the massive increase in productivity you can get in creating environments. Having dynamically lit environments in engines with pre baked lightning requires carefully placing emitters, triggering them on geometry changes and so on.

See when people argue “I wan’t dynamic and destructible environments” the problem is to a large extent the lighting. If you can blow a hole in the roof but the sun doesn’t shine in - you can tell something is wrong. So you can’t make a hole in the roof.

With GI you can crash a part of the roof and the interior lighting “just works”.

Re: Cornell McRay T'Racing

#37

Post by rzzzt »

pixelpoet wrote: post #28
alkonaut wrote: post #15

Earlier quoted context omitted.

Indeed and the first part is the first scene done in any ray tracer: https://en.m.wikipedia.org/wiki/Cornell_box

It's by far not the first scene done in any ray tracer, rather an early test scene for radiosity (diffuse-only global illumination, before path tracing was developed).

Which one is the oldest, Utah teapot, bunny, dragon, default material cube?

Re: Cornell McRay T'Racing

#38

Post by no_time »

alkonaut wrote: post #13

The real time ray tracing is a massive achievement. Tbf I never thought it would be possible to do in my lifetime (and it really isn’t, it’s a lot of impressive smoke and mirrors like reservoir sampling!) but this is really close to a path traced look considering how few samples it really is per pixel. All that aside, what really stands out with this demo is how nice the dev experience is. Lots of bits and pieces tha…

If you qualify RTX as "realtime raytracing" then it has been possible for a long time now. Of course this uses way more smoke and mirrors :)

https://www.youtube.com/watch?v=-Qw5bavWxBs

https://web.archive.org/web/20110519050817/http://exceed.hu/...

Re: Cornell McRay T'Racing

#39

Post by alkonaut »

no_time wrote: post #38
alkonaut wrote: post #13

The real time ray tracing is a massive achievement. Tbf I never thought it would be possible to do in my lifetime (and it really isn’t, it’s a lot of impressive smoke and mirrors like reservoir sampling!) but this is really close to a path traced look considering how few samples it really is per pixel. All that aside, what really stands out with this demo is how nice the dev experience is. Lots of bits and pieces tha…

If you qualify RTX as "realtime raytracing" then it has been possible for a long time now. Of course this uses way more smoke and mirrors :) https://www.youtube.com/watch?v=-Qw5bavWxBs https://web.archive.org/web/20110519050817/http://exceed.hu/...

No I mean it in the sense of using ray tracing for the full Global Illumination of a full game scene. Obvs there are lots of titles some a few years old where RTX is used for specific effects like specular reflection or ambient occlusion but where the lighting is still traditional.

Ray marching a SDF based scene is also pretty easy but that’s more like a world inside a shader than anything resembling a full game scene.

Re: Cornell McRay T'Racing

#40

Post by pixelpoet »

rzzzt wrote: post #37
pixelpoet wrote: post #28

Earlier quoted context omitted.

It's by far not the first scene done in any ray tracer, rather an early test scene for radiosity (diffuse-only global illumination, before path tracing was developed).

Which one is the oldest, Utah teapot, bunny, dragon, default material cube?

I'd guess the Utah teapot, it's been around since 1975. Cornell box is from 1984, and test scenes for materials are in some way a pretty recent thing, at least how they are used now; to me the modern versions started with Maxwell Render.
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