This is a great video essay! It baffles me that it only has < 100 views.

The Witcher 3 as shown here and most games with fully dynamic time of day and weather have no precomputed lighting, since there's no good way to store it. Baked lighting has been gradually dying. Instead there's a bunch of tricks and techniques that replicate the look of it. One thing you can do is precomputed ambient occlusion, that is, imagine the light comes from all sides, from the whole sky hemisphere, and then you store how much light reaches where, and you have essentially a map of places that the light can and cannot reach, you CAN store that, and then you just multiply your dynamic lighting by that, it makes things a little better, it's not perfect; but it's proven really little need for that with screen space approximate ambient occlusion (SSAO), where upon rendering a depth buffer, you just walk in the vicinity of each pixel in a few directions in the depth buffer and sample it to look for occluders, and it's a pretty sparse trace but it works, you can also incorporate some bias towards the real dynamic light direction into it, that can help too. The technique of precomputed bounce lighting is spectacularly old though. At first it was called Radiosity. Limited to fully diffuse lighting. You can see it in Quake 2, and i think the most prominent title might be Mirror's Edge, that's basically the look, Half-Life 2 used it i think as well. Quake 1 and 3 used direct-lighting baked lightmaps with hand placed secondary lights to simulate bounce instead, that's a commonly used approach as well. Ray tracing doesn't actually simulate photons. It simulates the rays in reverse, as if your eyes were firing them, and then for every hit surface and light source, checking if there's a valid path. But ray tracing hardware can of course do more than just that, path tracing among them. Path tracing is an unbiased algorithm which can be run bidirectionally from the eye or from the light source, and it requires a bunch of extra rays with the hope that it hits a light source OR the eye, it has a wasted ray problem. Don't expect all that much more dynamic worlds from raytracing. Because something that's REALLY good to have is precomputed visibility, or at least visibility that can be quickly tested, thus LARGE, solid and strategically placed occluders to hide most of the objects in the scene from you and from the renderer. An expansion of potential visibility set by one fold (i.e. places that are potentially visible from potentially visible places) or maybe two folds also gives you an audibility set, and a set of script activity, you don't need to compute any logic for entities which are outside this set. Another big problem in destructible world is that you might get yourself in a situation where you're STUCK, where a hole that you made is just the right size to get into it but not out of it, and i don't suppose you have a solution to that. As badly as games handle body presence, you can't even judge whether any given hole is your size or not, you're like a silly little ferret. This fragility of character physics is i think the main reason you generally see exactly as much or as little destruction as carefully foreseen by level designers, because lighting, well with some degradation we can deal with that, we can have it fully dynamic, it doesn't look the best but it works, and occlusion, well we could just have less stuff in general, but there just isn't a solution to getting stuck. One problem why rayracing is of moderate usefulness today is... well when you're doing rayraced production rendering, you fire hundreds of rays per pixel. Your home hardware (PC or console) can maybe do two, maybe 4 if you're extra lucky, a handful. And you're trying to reconstruct a cohesive appearance from that. So using it in moderation helps it visually not fall apart for the time being. I worked on an engine which was used in some Wii and Xbox360 games. So i'm not exactly an industry outsider.

Great video. It’s shocking to me how few people understand what ray tracing means. You really laid out all the benefits in a great way.

Good video! Mostly true! A lot of work actually goes into making scenes simple enough to bake out relatively quickly. Artists will often do several passes, each with more detail, as they get closer to final. So there are lots of techniques and workarounds to get around these downsides, but I have a feeling that people will view this type of light rendering like people view practical effects in movies vs VFX. One is outdated but has a certain charm that can't be really replicated through photo realism.

Great video! I’d love to see you revisit this topic regarding Cyberpunk’s overdrive mode with path tracing DLSS 3.5.

I see a golden age of game development, productivity and creativity once ray tracing becomes the status quo.

This is actually a really good video, very informative and easy to understand. How doesn’t this video have at least a million views is unbelievable. Easy like and subscribed.

W video very imformative Ray tracing is going to be amazing when It is practical. I cant wait to see when what Cyberpunk 2077 just did with ray tracing is the norm.

and now there is path tracing .. also a big step forword :D