How does Ray Tracing Work in Video Games and Movies?

[@BranchEducation]

We have a few potential topics for an upcoming video but can't narrow it down to one. Which would you pick? 1) How Lasers Work? 2) How Bitcoin Mining Works? 3) How Transistors Work? 4) How WiFi Works? 5) Recommend something else. FYI- we are already planning videos on GPU Architecture, CPU Arch, Generative AI, and Quantum Computers. The problem is that each of these requires a mountain of research and script writing/ editing to get a cohesive lesson. Therefore, we try to mix in videos that still cover complex topics but have a more straightforward script. For Example, for explaining CPUs- there are just sooo many different directions and ways to write the script vs. how bitcoing mining works a little more straightforward (yet still complex) of a script. Also, for my computer (Teddy) and the lead animator (Mike), we both use 3090ti graphics cards.

[@bluezul75]

Video on transistors would be great!

[@cwalcott48]

A video on WiFi would be excellent! Would love to see explanations of: - The different bands (2.4/5/6GHz) and how they interact with their environments, why some can go through walls, why multiple sources of the same frequency band operating on the same channel can interfere with each other. - How WiFi compares to Bluetooth/long lines/radio/etc. - Access points and how they operate together in large workspaces.

[@gandhiisback3940]

5) how transit systems work, like the inner workings of the NYC subway would be amazing

[@SlySk]

3, transistors ! They’re so mysterious :o Even after researching them I still can’t wrap my head around them.

[@llamasaveur]

+1 transistors

[@JaredOwen]

The amount of detail in this video is astounding - well done!

[@Abdullah-Muzamil]

details in your videos are also excellent

[@DemPilafian]

The amount of triangles in this video is astounding!

[@Eagle-182]

Big fan of your channel

[@andymoral]

Unbelievable and outstanding. Love your work!!

[@thawzinkhant1759]

The GOAT is hereeeee

[@_guber_]

Still can't believe that content of this quality exists free. Thank for your hard work❤

[@rajugundu268]

Yeah broi

[@dolo3]

I pay every month for premium and content this good is still worth whatever i pay now.

[@111111222223]

I love how contemporary your videos are. Most educational content, especially in computer science, tends to refer to outdated technology and/or use outdated figures, but you always use the state of the art that's currently available, which is very refreshing.

[@jonathansung8197]

Ray tracing is about 40 years old with SIGGRAPH papers from the 80s like Kajiya's.

[@ViciousTuna2012]

@@jonathansung8197 In your race to be a smartass you only showed how you didn't understand their comment. In the video he not only goes over how the core concepts were outlined decades ago, but how they're achieved on modern computing hardware. Hence, contemporary.

[@JesusPlsSaveMe]

Revelation 3:20 Behold, I stand at the door, and knock: if any man hear my voice, and open the door, I will come in to him, and will sup with him, and he with me. HEY THERE 🤗 JESUS IS CALLING YOU TODAY. Turn away from your sins, confess, forsake them and live the victorious life. God bless. Revelation 22:12-14 And, behold, I come quickly; and my reward is with me, to give every man according as his work shall be. I am Alpha and Omega, the beginning and the end, the first and the last. Blessed are they that do his commandments, that they may have right to the tree of life, and may enter in through the gates into the city.

[@LuisSierra42]

@@jonathansung8197 But they didn't explain the original paper or the earlier applications but the most recent ones

[@jonathansung8197]

@@LuisSierra42 everything they described (with the exception of the RTX GPUs and gaming) in the video was already established by the late 80s (BVH, global illumination, etc.). They didn't even mention anything about metropolis light transport, monte carlo methods, or photon mapping which were innovations of the 90s. This video is a basic introduction to ray tracing, and is not state of the art in any way. The only modern part it covers is the real-time applications for gaming where they make visual sacrifices for the sake of performance. If it were state of the art, it would also cover wave optics simulation (2024), which computes light as a wave as opposed to a ray, producing inference visual effects such as the rainbow glimmer of a CD.

[@LRiga]

I am always amazed by how you always manage to make extremely complicated and technical content accessible "to everyone." Thank you!

[@mahermagdy4604]

As a computer geometry developer, i am blown away by your easy to follow explanation. Keep it up

[@ExploringNew1]

Easily one of the best videos on KZbin

[@Khomann]

you commented this 3 minutes after the video was uploaded lol

[@ExploringNew1]

@@Khomann lol the first 2 minutes are still amazing

[@zxshd]

one of the best channels too

[@prsworld]

Every time!😂🎉

[@Sandfennec]

Ooh you better watch the episodes on how SSD storage works & the Transmission Electron Microscope 🔬

[@wedusk]

Once again, an amazing video and a perfect follow up to the one about rasterization. As a professional in the industry, I will be using this video for introducing new-comers to the field. Thank you for helping the community grow🙏

[@Mockermay]

It feels illegal to watch this for free

[@yay-r6j]

hopefully they keep it that way and find amazing sponsors and also get paid well from KZbin itself. content like this should be accessible to everyone, at any time. this info can help so many curious minds grasp such complex topics as these. much, much love!

[@aadhya8459]

But i dont have money🤕. I just hope these type of vids keep coming.

[@YellowFlash469]

true

[@niterlock]

20000 shell credits

[@danjan713]

Nice donation

[@jvitor.csantos]

Man, people who both created this video and the entire ecosystem for CGI like video cards, the way they work, etc. are so genius. It is unbelievable how complex this subject is.

[@hamza-trabelsi]

yes it is both amazing m complex but also simple . there is no such thing as 3D rendering , it is all 2d, it is all arrays of numbers and colors ,

[@rishavchakraborty9380]

Keep doing the great work! Love your videos!!!!

[@Sports_In_MotionX]

Funny how I watched this video while waiting for my render to finish... Stopped my render mid video, finished the video and made adjustments in blender based on the info I got from the bid. I now even understand the text that you get before the render starts (blender) BVH etc. This is quality content.

[@Doyle69]

30 years to get to a stage where Path tracing was possible, now we have a KZbinr using similar software on a High spec home PC creating us videos on how it was made possible, crazy times.

[@j.pj.p7143]

sir, it looks like you had worked on this, am i correct

[@juanromero-fi2cf]

my uni final animation project took 6 days on 3 pc with 1.2 ghz procs and 256 mb of ram back in 2001, thinking this same project would take less than an hour on my actual hardware is crazy

[@charlesabboud1613]

It’s astounding how complex ray tracing is and just how well made this video is..I knew it was very complex, if anything after your explanation, it seems even more improbable and more impressive that any CGI is ever done.

[@vishantshah3524]

I don't usually comment. In fact this is my first ever YT comment. This channel deserves to be highlighted by YT. Such incredible detail and knowledge at free of cost! Just insane. RESPECT 💯

[@atyla7067]

We need more of this type of educational videos on KZbin.

[@Tigrou7777]

20:09 the detail of the zoom into the 3090 GPU (GA102) is just incredible.

[@pinpointping6175]

Right? Nightmare texture 😮

[@sac_kri]

Bro they made new vid on GPU watch it

[@saladamista8226]

Every time I see a new Branch Education video in my feed, I think: "Time to get a little smarter." I haven't even started watching the video yet, but I'm leaving this comment because I know it's always done with the highest quality. Thank you very much Branch Education!

[@howdoes8242]

amazing work!!

[@kslavov]

The dedication and level of detail in this video are otherworldly!

[@mrmoneybagz]

As a Blender user, I have watched several videos on Ray Tracing. I can say that this is by far the best and most in-depth explanation I've ever come across. I've added it to my bookmarks.

[@UrielCopy]

Its kinda insane the level of detail and complexity in these videos! Slick animations with extremely good sense of how to explain and teach. Brilliant, amazing stuff, and im baffled that this is free..

[@tetradb_]

This video hits all the marks for me, it's top quality and incredibly well put together. From the rich subject knowledge, presented in a very palatable way for someone with less technical knowledge, while still getting to the nitty gritty. That's topped off with a streamlined script and narration, complemented by a well thought out, clear, easy to follow and well choreographed animation. 👏👏👏

[@fslurrehman]

Due to its philosophy of freedom and sharing, Branch Education is the leading educational channel.

[@fracta7]

I can't imagine the amount of time to research all this and make animation about it. Amazing work as always!

[@xeqqail3546]

24:46 here you go for this vid

[@That_Awesome_Guy1]

800 hours

[@beaconing7689]

you don't watch fully don't you?

[@cybercat2025]

AI should also help with the research

[@trumpisbackboi]

BranchEducation the youtube MVP, The holy bible of computer tech

[@kinggambo368]

True 🤞🏻

[@jcm2606]

25:57 What you're describing here isn't Lumen, but Lightmass, Unreal Engine's light baking system. Lumen doesn't bake lighting, instead it dynamically samples lighting along a set of low resolution screen-space and world-space probes, then resolves the lighting stored in the probes against the actual screen geometry. EDIT: Want to say that your visualisation of screen-space raytracing is probably the best I've ever seen, as it does an excellent job at showing the lack of information for off-screen and occluded surfaces. Whoever pitched that visualisation for the video, well done.

[@BranchEducation]

Ah, this is a good distinction. I spent many days trying to work through exactly what techniques Lumen used, and I was aware of the world-space probes, but needed to keep it to just a few examples of ray tracing in video games. Sorry that we mixed up lightmass and lumen. Also thanks for liking our screen-space!! It took a good amount of time to dynamically figure out the correct node setup in blender to have the scene change based on the 'camera view' / a set of planes to cut things up.

[@Navhkrin]

@@BranchEducation Lumen part is very inaccurate in video, but rest are so well made! Lumen is pretty complex algorithm that uses combination of distance fields, surface cards, screen space tracing and voxel tracing to achieve its results and would probably take 5-10 minutes if you wanted to explain it on detail. Heck you could make another advanced ray tracing video that covers Lumen's software and hardware paths, ReSTIR, radiance cascades and so on. If you guys contact Brian Karis, I'm sure he would be willing to help you clarify how Lumen works.

[@Zarsky88]

AFAIK Brian Karis is the developer behind the other key UE5 feature Nanite, not ​Lumen. @@Navhkrin

[@PAULO-gv6he]

The quality, depth and detail of your videos is crazy! Happy to pay something for this, if I was rich I would've sponsored you. Much love!

[@iguess7997]

13:10 so basically the camera acts exactly like the human eye. Except there is no human, no eye, no real light source or real object to be seen, its all just computers.. so insanely cool

[@rayargames]

Branch Education this is the best video you've ever made, we love you, keep it up!

[@nishant_bhardwaj]

You will watch their other video and say the same. That's how good this channel is

[@abhilasha4334]

We always underestimate how far we come in technology, doing that much calculation in less than seconds is massive, thank you for making a great video

[@jimmurphy6095]

I started ray tracing with POVRay back in the day even before programs like Moray came out. All text based and written in the programming script. I remember waiting overnight for my renders to finish. Awesome content.

[@abyabraham1845]

The depth you go with ease and still providing detailed explanation with these crazy graphical representation is AWESOME.

[@bigsurf77]

The quality of the video is insane, thank you!

[@douglasiram7937]

Thanks! I'll need to watch this more than once!

[@staryskies]

i just want to say I never really thought I'll see something like this,in this caliber and quality you guys are doing absolutely outstanding work,and hands down one of the best channels out there for those type of things

[@joao13soares]

I wish superb-quality videos like this one would be around sooner. I could sit for 3 hours of content like this but struggled to focus for 30 minutes during university classes on the same topic. So it wasn't a matter of lack of interest on the subject but rather how it was delivered. Glad that we nowadays have access to much more interactive options for educating ourselves.

[@Florianski]

The production quality is absolutely insane

[@joshuasolomon2142]

If Branch could teach every subject in school, the world would be a more brilliant place!

[@johnnysvensson]

Great video as usual!! One small inaccuracy i noticed around 3:20 is that normally you don't simply apply a texture to your model, instead you create and apply a material that consist of several different "textures", for example the actual surface texture, a normal map, a diffuse map and a specular map. I believe it's important to distinguish between the two in order to avoid confusion. EDIT: Back in the days of rasterization it was more common to simply apply a texture to your surface but the standard today is materials.

[@BranchEducation]

Haha, we're very aware of the complexity of textures on models. We just needed to make a simplified description of building a 3D scene before we dove into Ray / Path Tracing. Like- we skipped the entirety of keyframing/rigging.

[@johnnysvensson]

@@BranchEducation That's fair :)

[@jstsmvds]

I've not watched the video but I'm writing this comment for my friend who made animations from 2:30 to 16:00, and I want to say that you are working with the best chlenderist of all time, keep working with him, Sherdil Dovronov SILA 🇺🇿

[@lllllllllbek]

Keygen don't play

[@snopz]

This channel is one of the best I’ve come across, and it’s surprising that you have only 1.85M subscribers-this content deserves so much more recognition! Unfortunately, many people today spend hours scrolling through TikTok, Instagram, KZbin Shorts, etc., missing out on the kind of educational content that could truly impact their lives. Offering such high-quality content for free is incredible, and I deeply appreciate your effort. I hope your channel continues to grow as more people discover the value of what you provide. Thank you, and keep up the amazing work!

[@walidkartobi]

Can believe I get to watch this for free! Tremendous amount of time and effort has been put into this and I'm appreciating every pixel of it!

[@HostileTakeover2]

Amazing! This is like the modern equivalent of those old mechanical education videos. Like the one explaining a car gear box, or the one explaining differential steering from the late '30s which were the golden standard of explanation. They were made so clear anybody could follow these complex processes even if not understanding fully. I think the people who worked out the logistics of the concept would've loved to have had this as reference.

[@Kratoseum]

I do a lot of rendering in my work, you guys nailed this. Outstanding work!

[@Splntxx]

Easily the best explanation of these concepts on KZbin!

[@TheRealLink]

As a gamer for well, ever, as well as a pretty avid Blender user these days to both learn, game mod, and render scenes for others, this video was INCREDIBLY well-made! I instantly recognized the Blender scenes you loaded and chuckled as I've benched those numerous times with advancing hardware. It is pretty amazing how far we've come in such a short time - for example, while not a feature-film, simply compare the original FFVII Playstation opening from 1997 to the Remake's version in ~2022 for an example of how GPU and compute power have evolved. It's great that GPUs are still advancing rapidly and are not stuck in CPU 4-core hell, haha. The aspects covering BVH and other RT forms was great too as while I knew what they were, learning more is always good. Keep up the great work!

[@Jagjitgupta]

I'm also a 3D Artist and appreciate to Branch Education team, you all are Legends.

[@luxor935]

Props to the people who created this❤

[@MarcusMainali]

Your videos are Always Worth the wait!

[@cosmagabriela236]

Best explanation for why path tracing is so demanding on technology so far and also an unparalleled eduacational video.

[@xanderlinhares]

Note for viewers: this video details classical “ray tracing” and not path tracing but seems to use the terms interchangeably. That said, it’s still an incredible video.

[@parthfilmz]

thank you for creating high-quality videos explaining very complex topics in a simplified manner

[@carmelomancia580]

Never really understand how renderings works until now, this really explains everything

[@filipepinho3319]

This reminded me of the old times when I was studying computer science and I had to develop a simple ray tracing software in c++ with a openGL editor to composite the scene...

[@vadimg8126]

As a GPU software engineer - kudos, amazing video. However, I wish every pixel was indeed independent - you have dependency between neighboring pixels(if one pixel will be black and the pixel next to him will be completely white it will look awful). So in modern graphics engineers, blending is a must. So it's even more complicated than what is presented.

[@jcm2606]

Not to mention that modern GPUs compute multiple pixels together in lockstep, which can cause problems if the pixels are having to take different paths through the code due to divergent branching, or having to load data from different locations in memory due to divergent memory accesses. This is the entire reason why the 40 series of NVIDIA cards have shader execution reordering, as that reorders pixels to group pixels together if they're taking the same path through the code or accessing the same locations in memory.

[@HenryLoenwind]

That's what oversampling is for. With a thousand primary rays per pixel, you only ever get a black next to a white one when the divide between a black and white object exactly lines up with the pixels. Otherwise there will always be a pixel that samples both objects partially. And that is for a render without atmospheric (volumetric) effects. If those are on (and when you render with a thousand rays, you better have them on unless you want your result to look artificial), the scattering along the path of the primary ray will produce even more partial pixels. Please don't forget that this video primarily explains the ideal case, i.e. what big movie productions use. The optimisations you need to render in real-time on a single GPU are mentioned briefly at the end.

[@CaptainAlvin350]

Branch Education are really doing alot I learnt how battery work with them last year

[@Sportsbikeguy]

This was fantastic. I got lost about 2/3rds in but continued watching as I was just in awe of the brilliance of the animation. 675 hours is 28 days straight to animate this. Absolutely incredible.

[@dzxtricks]

People keep saying ray traced games aren't optimized enough even a 4090 needs dlss and whatever else. But after watching this, a game uses any form of ray tracing at all is a miracle 😅

[@lombredeshakuras1481]

That's exactly the point people aren't looking at. Having working real time ray tracing, even on some lower end hardware such as RTX 3060 or 4060, it's just a miracle and we are inches away of real time true photorealism. Each generations are just way better at tracing rays. It also accelerates game dev, but since performance is still an issue for now and we don't see much of it. With it, we'll also see more physics based interactions because now, lighting is done automatically and correctly whenever something moves. But in the next years, game dev will definitely be faster with ray tracing in mind and the absence of engine building at each change on the project. It can also be used for simulations like sound

[@NeovanGoth]

Absolutely. People like to complain about "lack of optimization", while not understanding what incredible amount of optimization went into both algorithms and hardware to make this possible.

[@iamagoodboi]

Typical AMDumbs praise Rasterization because RT run like 💩 on their cards

[@DragonOfTheMortalKombat]

Brokes cry and don't understand let them live in ignorance with old graphics. This video might be too much for them to understand lol

[@DragonOfTheMortalKombat]

​@@NeovanGoth agreed 100%👍

[@YadraVoat]

0:12 - Excellent animations as always, but unless I'm mistaken the T-65B X-wing can only fire when the S-foils are in attack position? 😎

[@hawkeye8765]

☝️🤓

[@JediSentinal]

Correct 😂

[@Byt3me21]

It's a common mistake

[@phoenix0166]

Priorities

[@Andrews.1]

Nerd alert

[@VieShaphiel]

I don't usually stop everything I'm doing when I see a KZbin video drops, but I had to do so for this one.

[@costinnovac6092]

The graphics used in this video is ridiculously high end. I was just perplex. Easy one of the best video.

[@ilynpayne7491]

I have been watching KZbin for years but this is next level of production and explanation this channel clearly needs more subscribers I really enjoyed watching this even though I'm not a video producer or graphics designer 4:53

[@thowheedh]

One day I will sponsor at least one of your video Insha Allah

[@SubatomicPlanets]

Yes, a new video! And it's about Ray Tracing!

[@grahamthomas9319]

👇Blender Artist loving this!

[@joelledbetter2926]

This is the best channel I've seen ...feel like I need to go back to school now

[@madxv3nom765]

This video is a masterpiece fr .. and deserves millions 🙌

[@mathysherbreteau9524]

Amazing content and beautiful vid !

[@eraofgamers]

25:00 Done✅

[@ernad395]

11:21 Sir, a second ray hit the towers.

[@Dontae.Hawkins]

😂😂😂😂😂😂😂 …. Wait…. Ima New Yorker 😢

[@Amox625]

😂😂😂😂😂​@@Dontae.Hawkins

[@princeajaero7903]

I am so glad that the editors use Blender for their video. As a Blender user, it makes the whole video easy to understand.😁#blender

[@MikeRadjabov]

we use Blender for all our videos, even for final editing 😀

[@mediaman1346]

After watching this video and Being a Blender user, I feel like I'm on a level playing field with the big boys of CGI software...so empowering😁!!!

[@antoniovinciguerra8982]

I can‘t say I can fully comprehend how I‘m able to play Star Citizen but this video sure has gotten me closer than ever to understanding this marvel that lives inside my computer case. Thanks!

[@aceofspades001]

*Scam Citizen 😂

[@paul921pdk]

Your videos are the best thanks.

[@BranchEducation]

Glad you like them!

[@mr.mechanicalcreationer1352]

Our waiting is end

[@Darzkiix]

The work put into these video is absolutely commendable

[@oi_sobagi]

This video is absolutely brilliant! I'm never taking Ray Tracing for granted ever. I came here after your video on how graphics in video games work, and now since you covered RT in a video of its own, I'm looking forward to the video on DLSS next. Keep up the great work!

[@SubatomicPlanets]

I feel like CGI has peaked in 2006 with Pirates of the Caribbean 2. Davy Jones is one of the most realistic CGI characters ever in my opinion. I think this is because CGI is just used too often today. Almost every shot has CGI in it in most new movies.

[@BranchEducation]

I agree. Davy Jones Cgi was really perfect. Tho it probably relates to the computational power of the computers. When teraflops became super cheap then any studio could make cgi and then they probably competed more on price and sacrificed the Davy Jones level of quality

[@KentRoads]

CGI is MUCHH more expensive than performing a lot of scenes irl! in one movie, it was cheaper to crash a jumbo jet into a hangar than CGI it lol

[@thenewculture.]

Percy Jackson King Kong 2005 is peak

[@prosiescoteau2152]

​​@@BranchEducation There's a really good video explainer on it if you search for it. The main things are that (1) the character had wet shiny skin which meant they didn't have to deal with subsurface scattering, just specular reflections. (2) the character's costume made his face be the only exposed skin he had. His forehead and neck are covered, so they didn't have to deal with making those wrinkle realisticly as he emotes and turns his head.

[@johnnysvensson]

and i bet there is even more CGI you don't notice.. The best CGI is the CGI you don't see :)

[@avricci]

It's been probably 5+ years since I last favorited a video. As a fellow colleague 3d artist, I thank you very much for this.

[@farsheedd]

Oh, this is mindblowing how you created every small detail in both models and narration 🤯

[@esmith2k2]

I have to say, the level of animation in these videos is absolutely astounding. You cover incredibly complex topics and explain them thoroughly with incredibly helpful and descriptive animations to allow for easy understanding. I'm blown away.

[@AMITH11]

It's amazing that this sort of high quality videos are available for free

[@musfidurrahmanmusfic3986]

The workforce and dedication you had to put in this video is just mind blowing. Keep it up brother

[@shownickbhattacharjee2158]

I wish i were working with you. You guys such a genius... Very fortunate to have such channels.. keep it up.. 👍

[@johndah3984]

I wish branch education has a course where we can buy and learn such detailed animation. I just love branch education ❤. I regularly refresh their page to see if a new video is out!

[@tayyabchadhar3876]

this is your first video i have seen and i am already impressed.

[@minomxmk4225]

its mind blowing how i just can't describe how incredible is this channels videos are!

[@E.T.S.]

Great video. It also sheds a light on AI generative programs and their controlnets. I was flabbergasted how Stable Diffusion really "knew" distances and orientations of surfaces in images it created. Until controlnets I thought AI was just copy-pasting objects from different photos together, and until my 3080 I thought that realtime raytracing was just a marketing claim. Thanks for making and sharing.

[@arjunverma1520]

Most Informative Channel on YT

[@paranthamanyathursiyan]

I'm a Student studying Advanced Level Maths stream, and already very interested in Mathematics real-time usage and Gaming, Tech & Physics, But this channel gives a wider range of knowledge... thank you, please continue to make about that (Vector, Trigonometry, Physics, Algorithm & more) 🙏👌✌

[@jestinvarghese1048]

The way you guys explain the concept is amazing. I develop GPUs and I wish I had seen these videos while learning the architecture.

[@psumant5866]

Thank you for helping millions for free🙌

[@daniyaldani5042]

Please make a video on compilers that translate a high level language into machine language i hope you will Your channel is most amazing channel i have ever seen Thanks to you for your incredible work❤

[@bernaferrari]

You should make a video (or even a course) on how you make these videos. I would pay.

[@iamklevy]

I just can't wrap me head around the process of making this video it's amazing to watch this on youTube nowdays, very thankful for finding people like yourselves who wanna add something valuable to the world. big love from Egypt 😘😘

[@davinci3043]

One of the best videos on youtube, from the best channel of the platform.

[@mikekelliher99]

Phenomenal work! I’d also love to see you team explain how Remake/Remasters for games work

[@melianatamsuli2114]

thank you youtube algorithm for recommending me this epic stuff

[@frumpeting]

Visually paced, explained, and demonstrated so well. I am a veteran and have tried to explain this from the Mental Ray days. Well done.