[dev_snd]

This is the reason it only works with directx 8 or 9: they have a pretty rigid render path with a clearly separated vertex and pixel shader pipeline.

For directx 8, you would for example specify light sources as part of special draw calls to the directx API, which makes it easier to translate them to a ray traced scene graph.

Shader tools like reshare also use heuristics to detect which of the framebuffers contains a depth map to add effects like SSAO to older games.

I imagine that rtx remix can to similar things to detect where in a shader the light coordinates are stored: after all most shaders look pretty similar when it comes to implementing a Phong shader etc.

[qikInNdOutReply]

For everything over it, nvidia would have to expose the byzantine monstrosity that is the drivers they wrote, that detect games and hotswap the buggy developer shadercode out for working nvidia shader code. And they could do that for older titles. It just wouldnt be neat.

[ls612]

I mean there’s plenty of DX9 games from the 2000s that would look amazing with an RTX touch up so that doesn’t seem like too bad a thing

[c0m]

Hell, even CSGO is running on DX9.

[ls612]

I wanna see Rollercoaster tycoon 3 with an RTX overhaul that game had a lightning and shadow engine ahead of its time.