3 HN users recommended this explainer3 months2021–2025score 3
Years with an HN recommendation, 2007–2026
HN recommends it as a good overview of what ray-traced lighting changes for developers and players.
Digital Foundry's Alex Battaglia analyzes Metro Exodus Enhanced Edition, the first AAA game built around ray tracing. It covers the new global illumination, emissive lighting, DLSS and performance on AMD and Nvidia hardware.
“is a good overview of why this is such a huge leap forward for developers and players alike.” (HN, 2021)
Real-time ray traced reflections are an impressive trick, but real-time global illumination is where this tech shines IMO. This Digital Foundry video ( [this video] ) is a good overview of why this is such a huge leap forward for developers and players alike. Metro: Exodus EE (the game discussed in the video) is the only game I've played that really shows what 'RTX' and similar GPU hardware is capable of, IMO. Even CP77, which was supposed to push modern systems to their limit, feels like its ray tracing and GI stuff is janky and tacked-on.
Overview of real-time global illumination benefits in games
Here is a good video by Digital Foundry looking at Metro Exodus Enhanced edition with devtools. Where they show what raytracing is and how it differs from regular lighting. [this video] simplified tldr: with raytracing you build the environment, designate which parts (like sun, lamps) emit light and you are done. With regular an artist has to spend hours to days adding many fake lightsources to get same result.
Metro Exodus Enhanced Edition uses RT for basically all lighting, doesn't it? [this video] Same with Minecraft RTX [link] Though both still calculate the lighting over several frames, so if you want to be pedantic you could argue that it's not strictly real time.
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