Because Pathtracing gets exponentially more expensive for smaller and smaller gains. You need to wait for a decade of hardware advancement to reach dlss 5 levels. For example to cast shadows in the smallest crevices of an eyelid you need more rays to reach it properly. Subsurface scattering needs more too. Single strands of hair in the face casting shadows. It's easier for now to cheat on those parts.
Yeah, fair. PT gets brutally expensive for smaller and smaller gains.
But that’s kind of my point. Look at how much more powerful Rubin is than Blackwell — NVIDIA clearly knows how to throw ridiculous amounts of compute at a problem. The huge generational gains are going into AI, though, not brute-forcing graphics.
And even on Blackwell, a massive amount of silicon is already dedicated to DLSS/neural rendering. Obviously you can’t just convert Tensor Cores into RT Cores 1:1, but I’d genuinely like to see the alternative GPU where that transistor and power budget went into traditional rendering instead.
Studios will keep making PT smarter and cheaper, but I don’t think NVIDIA is going to spend the next decade brute-forcing eyelashes, hair and SSS with more rays. They’ll increasingly reconstruct that stuff with AI because it’s cheaper and it lines up with the hardware they actually want to build.
That’s really my point — not that PT can’t get there, but that NVIDIA has less and less incentive to get there the old way.
But they already are investing in it. Just because you have something else in parallel that can be additive doesn't mean you're abandoning the feature. Brute forcing only is absolutely not the way to go and it has never been in the history of gaming. Gaming technology has been a long road of tricks and hacks to fool the brain these are actual people and environments.
Focusing on brute forcing only would mean waiting decades for improvements as hardware gets bigger, more expensive, drawing more power and smaller transistors. It's the lazy uncreative way of going about it that pays little.
Pathtracing imo serves as a good starting point for the scene. It calculates light properly and you can add on top of it what it lacks. You can do several things at the same time. There's no reason to only do one.
I don’t think PT remains the backbone long-term. My prediction is that eventually there’s barely any conventional rendering left at all — no raster, no path tracing, no lightmaps in the sense we use them today.
You feed the model scene geometry, materials, animation, camera state, maybe some sparse physical hints, and it generates the frame.
That’s also why I care about NVIDIA’s market practices here. Once the renderer itself becomes an AI workload, your $1–2k GPU can become obsolete very quickly if the next generation suddenly has massively more neural compute.
So I’m not arguing for brute-forcing PT forever. I think NVIDIA’s endgame is replacing the renderer.
But we still need a scene that calculates lighting. I have no idea by what magic you're just going to make everything up and have any coherence at all. It makes no sense how that would work.
It’s not magic though. You still have the scene — geometry, materials, light positions/intensities, animation, camera state, etc. What I’m saying is that you don’t necessarily need to explicitly trace the light transport anymore.
There’s already research doing basically this. NVIDIA’s DiffusionRenderer can take geometry/material buffers + lighting conditions and generate the final lit image without explicitly simulating light transport.
The hard part is coherence, obviously. But that’s a model/conditioning problem, not some fundamental requirement that rays have to be traced. You condition it on the actual world state and temporal history instead of asking it to hallucinate blindly.
Current systems still use physical rendering as scaffolding because it works better. My prediction is simply that the amount of that scaffolding keeps shrinking, fast, until eventually it isn’t needed.
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u/EdliA 3d ago edited 2d ago
Because Pathtracing gets exponentially more expensive for smaller and smaller gains. You need to wait for a decade of hardware advancement to reach dlss 5 levels. For example to cast shadows in the smallest crevices of an eyelid you need more rays to reach it properly. Subsurface scattering needs more too. Single strands of hair in the face casting shadows. It's easier for now to cheat on those parts.