Which is the correct starting point of any performance optimisation with code. NEVER just assume you know what is slowing the program down. Measure the performance „in action“. Then you start your changes.
Haha, I didn't even notice that, Jacco is a former colleague of mine, back from when I worked at Davilex Games, small world indeed. Really interesting video, I've been creating some real-time ray-tracing shaders, but nothing using triangles yet.
For your next coding adventure you should try some multiplayer sync stuff if you haven't already. I recently have gone down a rabbit hole of different types of network sync models and there is still a lot of nuance that is left ambiguous in even the most detailed blog posts. Something that I would personally love to see.
@@SebastianLague yeah I always wondered how all of the battlefield games were able to host 64 players, events, vehicles, explosions with pretty good efficiency (benchmarked with my old crappy wifi connection) and all of that good stuff:)
My absolute favorite part of your videos is that the tone of your voice is like you are _smiling_ while speaking. I do not know why, normally I would consider it condescending, but from you it sounds _honest_ People who code well are rare. Equally rare are people who can explain well. People who can do _both_ are exceedingly rare. You deserve every bit of praise you get.
That was awesome. One of the structures I've used in the past when I have all the data ahead of time is a Sort-Tile-Recursive (STR) R*Tree. You sort the data in space first, then build the tree from the bottom up. The result is a very well balanced tree that is extremely quick to query. You then set the maximum number of children in a leaf, so you get even performance. I don't know if the query times would speed up that much after your final iteration, but my guess is, the build time would be infinitely quicker. As always, just an extremely informative and entertaining video!
these coding adventures get more and more complex. I reckon Sebastian's working on something big, but first has to learn every technique to its fullest before starting and then finishing it
Very impressive results, bravo. I keep being in awe by how you manage to make things work first, then optimize it in a structured way and without getting weighted down by premature optimizations and such.
If I were to make a guess, some of the content order is following papers / intuition and the rest is messing up a bunch, taking notes along the way, and then reforming into a delightful journey for viewers. Sebastian is a wonderful storyteller that I bet embellishes certain points and spends extra time on debugging tools for us. :)
Hey Sebastian, cool video! There's a slightly different approach that would let you try every possible cut in the SAH without too much additional cost. Right now you're evaluating each cut by looping over all the triangles (O(N*K) cost for N triangles and K cuts), but this does not take advantage of previous evaluations. Imagine you sorted the triangles along one of the axis, then computed and stored the bounding box of each prefix and each suffix of the triangle list. Now you can evaluate each cut in constant time (child A corresponds to a prefix of the list and child B to a suffix). Sorting has cost O(N log N), but then you can try all the cuts along that axis in O(N) time. Overall, the cost is O(N log N), which should be much better than O(NK) for large values of K. Here is an outline of the general approach: sort tris along the x axis prefixes = array of length n prefixes[0] = bounding box of tri[0] for i = 1 to n-1, assign prefixes[i] = bounding box union of prefixes[i-1] and tri[i] suffixes = arraay of length n suffixes[n-1] = bounding box of tri[n-1] for i = n-2 to 0, assign suffixes[i] = bounding box union of suffixes[i+1] and tri[i] for i = 1 to n-1, the cost is i*surfaceArea(prefixes[i-1]) + (n-i)*surfaceArea(suffixes[i]) As described, the idea involves performing three sorting operations at each node of the tree, but this is not strictly necessary. If you sort all the triangles along the three axis just once at the top level, it's possible to preserve the order as you go down the tree construction algorithm. This might be too complicated to implement while keeping the code readable, though.
Your detailed explanation style is very much appreciated. It's often a tiny "practical" thing between "the theory" and "the final program" which is the biggest coding hurdle to overcome. Your videos are great to overcome these hurdles and learn how to approach such problems in general. Important skills well taught.
yeah it's been like 5 years since he made that comment about voxel erosion, I've been binging cave exploration videos and thinking about how to approach doing it myself hahaha
@@ms-fk6ebI'm sure I heard him mention the idea of tectonic plate simulations for the planet generation way way back and I think that'd be really cool to see.
Your visualizations are immensely beautiful and helps understand complex concepts like BVH. I am not lying when I said, I read this and implemented this myself, but I don't believe this is what my understanding was! Much love to your work
Also minor suggestion, add option to TIP on youtube videos. That way it would be easier for me or others to support your work without having to through Patreon.
The exploratory nature of your videos is why I will spend an hour of my life the next available moment I have watching your channel. I love learning, and as a non programmer and you just make it so fun and easy to understand. Thank you for the knowledge and enthusiasm you give me to keep knowing more. :)
it's been over a year since a fellow game programming student introduced me to the "cult of sebastian lague" (his words), and i'm so glad because your content is unbelievably lovely to watch (over and over). many times, i've rewatched various episodes of coding adventures to rekindle my joy for programming, and it always works. thank you, Bob Ross of Software Engineering
always excited to watch these videos, even though i dont understand much of it, the things you accomplish are so cool to see and its nice to learn something i have no idea about!
Two things I love about this channel, your ability to break down really complex programming concepts in to something easy to get my head around and the fact that your test and explainer side projects are damn near finished projects in their own right. Love it all!
The result is excellent, and the explanations are great. I think the key to sebastian's success is his attention to the small details. When he explains he may put a slight animation that you only see for 3 seconds in the video, but he has taken the time to prepare it carefully. That enhances the quality of an already 100/100 content. Thanks for taking the time to do the remaining 20% of things that enhance the content so much. Greetings from a big fan. Keep it up💪💪💪
Tbh I really love your videos. Your voice always feels like you're enjoying every moment of the explanation. Not only it gives both coding knowledge but also inspiring for me to continue my coding journey. I think it does the same things for other people too. Thank you for posting those videos!
Really great job with switching to an array of index values for your stack and leaving the nodes alone in their own array! The reason this is much better is because primitive types like floats and ints are always copied since they're considered trivially copyable (i.e., they don't take much time to copy at all and the computer could do it in its sleep), but when you have a lot of them, that time adds up. Now instead of copying all of the node data each time new nodes are pushed and popped from the stack, only single integer values are copied, which reduces the overal number of copies by a lot. Additionally, arrays are constant-time lookup, meaning no matter how big an array gets, it will always take the same amount of time to access a value. This is because the index values are actually just memory offsets, meaning only a single addition and multiplication are needed to go from the start of an array to a particular element. This means that you ended up trading in the cost of a bunch of unnecessary copies for the constant-time lookup of the nodes. I definitely believed that result when I saw it! Also I'm glad to see you getting more detailed about how computers work! You actually optimized your code to prevent cache misses! Your videos are so relaxing to watch, and your coding adventures cover all of the things I want to do, but simply don't have time for. I cannot appreciate enough the effort you put into these videos! Please keep them coming!
It's perfect timing. I’ve been diving into ray tracing concepts for about a year now, and it's impressive how you've managed to pull this off so quickly. Your video is inspiring and gives me some new ideas to explore. Keep up the great work! 👍
I love the speed and pacing you go over things. I find a LOT of programming/tech channels on youtube they just speak at an insane pace like they are gonna explode if they stop talking and makes it so hard to watch. Your videos? *chef's kiss*
One thing that I love about your videos is (the fact that && how) you show the optimization process: you briefly explain the idea behind the changes in code, show the actual changes and my favorite part - show a chart that shows the quantization of how productive that change was. I love seeing charts like that, but the whole process is also very entertaining to follow. How you come up with all these different ideas and what difference they make, love it.
At 40:38 You have a struct that contains two float3s and two ints. If I'm remembering correctly, due to the byte alignment this will actually result in 48 bytes. because unfortunately float3s round up to 16 bytes for alignment and the 2 ints (due to the highest alignment in the struct being 16 bytes) will also take up 16 bytes. I'm not entirely sure how well you can do this, but you might try stuffing the 2 ints into each of the float3s to make two float4s. resulting in a true 32 byte node. Not 100% sure about how much better this is though.
That depends on what language is used. HLSL aligns StructuredBuffer tightly. So in this case no extra padding is added. If it was a cbuffer you'd be right or if it was GLSL. It is still a good idea to move the int before the other float3 though, as this won't have weird behavior if you do want to store it in a cbuffer somehow..
@@nielsbishere This "align up to 16 bytes" behavior is not required: the default setting of "shared" (and "packed", which is similar) leave all details up to the implementation. The option of "std140" does introduce this alignment, however, but the newer "std430" does not.
@@pitust std430 does align float3 (or rather, vec3, which is the glsl variant) to 16 bytes. But it it doesn't have the 16 byte array stride that std140 has. For example: float[4] -> in std140, this is "similar" to float4[4], in std430 it is stored tightly like a single float4 A similar rule exists for structs in std140, which std430 also gets rid of. But std430 still has the special alignment rule for vec3.
I really really love the humour, the in depth explanations, the animations, pretty much everything. It feels so relaxing and like you really care abt everything which makes it so enjoyable to watch
Incredible Video, I love the beautiful explantation cut-aways of all these complex and hard to grasp concepts that are easy understandable thanks to you. Great work :)
I have watched you evolve your skills over the years and you have in front of me become a god. I started developing a bit before I found you on youtube 5-6 years ago and it's so fascinating to me to see you develop and also see me develop in the process. I love your videos and hope to see you for another 5-6 years making more amazing content like this.
"Hi Sebastian! I’ve been following your content for a while, and your videos on procedural generation and game development are incredibly insightful. I’m working on a voxel-based game inspired by Minecraft, and I was wondering if you’d consider making a video that goes in-depth on voxel world generation, similar to how Minecraft does it. It would be amazing to see your take on chunk loading, terrain generation using noise functions, and optimization techniques for creating large worlds. Your expertise and clear explanations would be incredibly helpful for many aspiring developers like me! Thanks for all the great content you’ve shared so far!"
HOLY DAMN THIS GUY BLEW UP. Context, I watched this guylike 8 years ago(maybe more but it feels like 8, 20k followers thought he was underated af, actually had a chat with him briefly about how to reverse an algorithm for I think it was moving platforms, quite a shock to see him over 1 mill, its like seeing and old friend and being happy for their success, feels good :3.
Whenever i see a new video released by Sebastian i just want to close off the rest of the world and enjoy it. Sebastian - I have no chance of ever being even a fraction as clever as you, but the way you explain things makes it really easy to follow and understand... Its such a great experience knowing that you will leave the video a little cleverer and more aware of things. The way you tackle problems and overcome them is really helpful. I cant wait to start implementing some aspects of these learnings into ideas i have. Thanks for making the internet a better place with your videos!
I'm pretty sure that reprojection just allows for the reuse of render data from frames where the camera is in a different position, and doesn't actually decrease the amount of noise when the camera is static
@@user-dh8oi2mk4f For realtime previews it's very useful. For offline renders it doesn't reduce the noise. And in fact reprojection would add bias. For that, you should probably use ReSTIR (DI/GI/PT) or a spatial denoiser (adds bias though).
How about a kd-tree? It is a more efficient data structure for static scenes. It is so efficient because it can stop as soon as it intersects with something inside a bounding box, as it gives distance sorted boxes. The intersection math is also waay faster!
Build times and splitting triangles can be a problem there, but if it can be baked or is just for a demo it's a good option. It will also force you to build on the cpu
A quirk is that a triangle can't be split like that (well, it can, but it makes things more complex): a BVH can have each side overlap enough to get the triangles on each side fully contained. It's not a complete loss though, you can generally simply put the triangle on both sides of the tree.
This did not feel like an hour. Well done on the video 👏 Here's to hoping you continue on exploring more and more advanced raytracing topics. This kind of content is to die for.
As I learn more about programming I’ve started to realize just how much you are actually doing, you make it look so effortless I didn’t comprehend just how much you wave away with a quick sentence, when I was learning compute shaders I watched your earlier raycast videos and you explain everything so clearly while doing such complicated stuff, your videos are always so informative and have helped me learn a lot
I love how you explain code and shows us your little mistakes in there as well. It shows the natural thought process and shows that even you are human (even though you create these wonderful visualisations). Amazing work!
This might be very inefficient but I, as a person who doesn’t code, have an idea. What if the rays were emitted from the camera, meaning that you don’t have to render any rays that don’t make it to it?
I love seeing how each change increases the performance, and how certain changes benefit (or require) other changes in order to actually bring a benefit. I similarly loved watching the different operations of the chess bot play against each other.
Sebastian: uploads a video *fifteen treseptagintilion years pass* Sebastian: uploads a video Edit1: no way I got 11 likes that’s never happened before!
This video is fucking AWESOME. You have such a talent for displaying these metrics, and it is so exciting to see the performance go up, to see the bounding boxes become more ghost-like as you're running all these tests... so cool.
I have done this in a class 2 years ago so I knew exactly what you were doing and still I watched a one hour long video just because the narrative and visualization are so well made. Thanks a lot for this!
Wonderful video as always! I recently saw a presentation by EA on how blue noise using the golden ratio is a huge improvement to perceived quality when rendering, since each pixel is randomized with respect to its neighbors rather than the full spectrum. This could speed up rendering by lowering the number of rays needed, and helps a lot with depth of field blurring which can look patchy at lower quality with white noise. What's also neat is that blue noise applies to any pseudorandom function by making the frequency higher. Essentially, it makes the next roll related to the previous roll and allows the gambler's fallacy to no longer be false.
what always captivates me is the way you visualise everything, especially the debugging. My life would be so much easier if I went past print statements 90% of the time 😂
Wow! You're doing an amazing job at making tough topics accessibly understandable to a wider array of aspiring graphics programmers! I really appreciate what you're doing here.
This Channel is really one of the best educational channels out there for this kind of topic. So much knowledge for free. Really good demonstration. Thanks for so much effort you definitely put into your videos
The experience of watching your videos while having dinner is so awesome. Thanks man, as a software developer I really appreciate all the work you've done with the audio, voice over, research, code and incremental changes 🤝
your presentation of the subject matter is the gold standard! the way you show how everything works and the highlighting of the code as you explain it 😗👌
This is really a great video! I love how your editing got more visual-based rather than code-based, and it made the video riveting despite beeing nearly a hour long
Day's always great when a new Coding Adventure video comes out. I can't wait to see all the probability light biasing stuff you mentioned. It was one of my more favorite things when tinkering with ray tracing, and I think you'd do a MUCH better job explaining it than some words on a screen
OMG YES I WAS SO LOOKING FORWARD TO THIS SPECIFIC VIDEO !!!! I made a raytracing engine because (or thanks to) you, you're an inspiration for coding and learning
You will not believe it if I said I've been watching your channel for over 4 years now and I have just realized today that your name is Sebastian *Lague* , always thought it was Sebastian *League* how have I not realized this
You know it's good when the youtuber pulls out the research paper. I love this channel so, so much. Makes me wanna go out and write some code just because how fun it makes it look!
"Just recursively split the children in half" is my new favorite Sebastian Lague quote.
The venn diagram of data structure terms and serial killer terms is a bit closer than you think 😅
This is the type of thing I laugh of
reminds me of the "are you being intentionally dense?" scene
I was zoning-out a little, but hearing that got me immediately focused again.
Salomon Lague
I’ve never been so excited to watch an hour long coding adventure before
Mee toooooo!!!!!
I more excited that I have an hour long video to watch while I wait for a game to install
Wait, that was almost an hour? I suppose it was!
Same!
the font vid was hype af too tho
"But sometimes, I suppose, one has to prioritise the computer's happiness over one's own."
No. The computer must suffer lest _we_ suffer instead.
@@GeorgeTsirosBut if the computer is happier now, then its work will be done faster, so we can be happy with that work sooner. It's a win-win!
@@ValeBridges It was mostly in jest
The true Bob Ross of programming.
@@GeorgeTsiros In my now decade of programming, I couldn't agree more
> I want to measure our inefficiency so that we can track improvements to it
what a philosophy
maximum inefficiency is pretty much my life motto
Which is the correct starting point of any performance optimisation with code. NEVER just assume you know what is slowing the program down. Measure the performance „in action“. Then you start your changes.
Humm, how would you do it if not by finding the innefficiencies?
OMG you've found the blog of my thesis supervisor (JBikker)! My thesis is related to BVHs so this video is a treat to watch :)
Haha, I didn't even notice that, Jacco is a former colleague of mine, back from when I worked at Davilex Games, small world indeed.
Really interesting video, I've been creating some real-time ray-tracing shaders, but nothing using triangles yet.
Fellow Jacco student!
It's surprising how often he comes up in my own research 😄
Your supervisor has a very rich and informative github.
Hey Sietze. :)
@@jaccobikker Amazing to read that you are still teaching. The graphics course was the most engaging and fun course I've had the pleasure of taking.
For your next coding adventure you should try some multiplayer sync stuff if you haven't already. I recently have gone down a rabbit hole of different types of network sync models and there is still a lot of nuance that is left ambiguous in even the most detailed blog posts. Something that I would personally love to see.
Perhaps, if I’m feeling brave!
@@SebastianLague yeah I always wondered how all of the battlefield games were able to host 64 players, events, vehicles, explosions with pretty good efficiency (benchmarked with my old crappy wifi connection) and all of that good stuff:)
@@SebastianLagueseconding this suggestion, although I understand the hesitation 😅
Network code is the path to madness
@SebastianLague The world of networking has always been a mystery to me, so I would love to see you cover it.
18:10 the arm waves in the reflection was so real 😂
A hallmark of graphics programming
@@epiklizard6629 I've been getting back into Vulkan and yeah...
I wondered if I was the only one who saw that
Side channel leaking his appearance
I was searching for this comment
"Where we left off a year or so ago" dealt me 1d6 of psychic danage
2d20 of old age
It shows in your spelling😮
So real, it felt like only a few months have passed
@@bactrosaurushuh
My absolute favorite part of your videos is that the tone of your voice is like you are _smiling_ while speaking.
I do not know why, normally I would consider it condescending, but from you it sounds _honest_
People who code well are rare. Equally rare are people who can explain well. People who can do _both_ are exceedingly rare. You deserve every bit of praise you get.
That was awesome. One of the structures I've used in the past when I have all the data ahead of time is a Sort-Tile-Recursive (STR) R*Tree. You sort the data in space first, then build the tree from the bottom up. The result is a very well balanced tree that is extremely quick to query. You then set the maximum number of children in a leaf, so you get even performance. I don't know if the query times would speed up that much after your final iteration, but my guess is, the build time would be infinitely quicker. As always, just an extremely informative and entertaining video!
I've never heard of that, but it sounds interesting -- will check it out. And thanks, I'm happy you enjoyed the video!
How did you get to see the video that fast
How tf did u watch 1hr video and replied when it only came out 1 min ago
@@dogeron8132 60x speed
How tf did you comment 23h ago when video was uploaded 18mins ago??
I hear the "hello everyone" and I drop anything just to watch it. 10/10 dropped my phone on a lake.
On??
@@willmungas8964 yes, on.
Water physics are a WIP...
@@Xa31er lmfaoooo
@@Xa31er mine bounced off of it. Its still bouncing, it never stops. I dont know what im doing wrong
frozen lake
these coding adventures get more and more complex. I reckon Sebastian's working on something big, but first has to learn every technique to its fullest before starting and then finishing it
The perfect Game Engine, offering the best performance on every possible aspect hahahahah
Sebastian in 50 years: Hello everyone and welcome to another episode of Coding Adventures. Today, I wanted to try simulating our universe.
He's actually working in reverse. Started out creating a universe, now he's on figuring out light.
at this point he's just doing his own thing for its own sake none of this is necessary for a game project or really anything past tech demos
@@ClaffAMV with incrdeible preview rendering
Very impressive results, bravo.
I keep being in awe by how you manage to make things work first, then optimize it in a structured way and without getting weighted down by premature optimizations and such.
If I were to make a guess, some of the content order is following papers / intuition and the rest is messing up a bunch, taking notes along the way, and then reforming into a delightful journey for viewers. Sebastian is a wonderful storyteller that I bet embellishes certain points and spends extra time on debugging tools for us. :)
Thank you!
the old motto of software design
make it work
make it right
make it fast
it's simple, but helps a lot
babe wake up sebastian uploaded
I hope he keeps these monthley uploads up that would be awesome
@@warriorsfg no 🅱️itches😔
exactly
Very nice video. Nice illustration of the BVH concepts! Greets, Jacco.
Your student and an old colleague commented on this video as well. Just letting you know in case you wanted to say anything to them.
Hi Jacco!
this guy a real one fr fr big shout out
Hey Sebastian, cool video!
There's a slightly different approach that would let you try every possible cut in the SAH without too much additional cost.
Right now you're evaluating each cut by looping over all the triangles (O(N*K) cost for N triangles and K cuts), but this does not take advantage of previous evaluations.
Imagine you sorted the triangles along one of the axis, then computed and stored the bounding box of each prefix and each suffix of the triangle list. Now you can evaluate each cut in constant time (child A corresponds to a prefix of the list and child B to a suffix).
Sorting has cost O(N log N), but then you can try all the cuts along that axis in O(N) time. Overall, the cost is O(N log N), which should be much better than O(NK) for large values of K.
Here is an outline of the general approach:
sort tris along the x axis
prefixes = array of length n
prefixes[0] = bounding box of tri[0]
for i = 1 to n-1, assign prefixes[i] = bounding box union of prefixes[i-1] and tri[i]
suffixes = arraay of length n
suffixes[n-1] = bounding box of tri[n-1]
for i = n-2 to 0, assign suffixes[i] = bounding box union of suffixes[i+1] and tri[i]
for i = 1 to n-1, the cost is i*surfaceArea(prefixes[i-1]) + (n-i)*surfaceArea(suffixes[i])
As described, the idea involves performing three sorting operations at each node of the tree, but this is not strictly necessary. If you sort all the triangles along the three axis just once at the top level, it's possible to preserve the order as you go down the tree construction algorithm. This might be too complicated to implement while keeping the code readable, though.
Your detailed explanation style is very much appreciated. It's often a tiny "practical" thing between "the theory" and "the final program" which is the biggest coding hurdle to overcome. Your videos are great to overcome these hurdles and learn how to approach such problems in general. Important skills well taught.
Can't wait for more fluid simulation next!
What about the volumetric effects?
yeah it's been like 5 years since he made that comment about voxel erosion, I've been binging cave exploration videos and thinking about how to approach doing it myself hahaha
Or rendering voxels. I’ve gone down that rabbit hole and I have yet to return. D:
ray traced fluid simulation with refraction and caustics
@@ms-fk6ebI'm sure I heard him mention the idea of tectonic plate simulations for the planet generation way way back and I think that'd be really cool to see.
Your visualizations are immensely beautiful and helps understand complex concepts like BVH. I am not lying when I said, I read this and implemented this myself, but I don't believe this is what my understanding was! Much love to your work
Also minor suggestion, add option to TIP on youtube videos. That way it would be easier for me or others to support your work without having to through Patreon.
I fell asleep watching this video and I'm not even joking, you have the calmest voice and I wouldn't trade it for anything!
hes going to be like "do i take this as a compliment (calm voice) or an insult (not engaging)" LOL
No it was engaging, I was just pretty sleepy I guess 😅 great video 👌@@pvic6959
Same! I was watching it last night and nodded off before I could finish, it’s too calming. I’m back to see the rest this morning though.
The exploratory nature of your videos is why I will spend an hour of my life the next available moment I have watching your channel. I love learning, and as a non programmer and you just make it so fun and easy to understand. Thank you for the knowledge and enthusiasm you give me to keep knowing more. :)
it's been over a year since a fellow game programming student introduced me to the "cult of sebastian lague" (his words), and i'm so glad because your content is unbelievably lovely to watch (over and over). many times, i've rewatched various episodes of coding adventures to rekindle my joy for programming, and it always works.
thank you, Bob Ross of Software Engineering
always excited to watch these videos, even though i dont understand much of it, the things you accomplish are so cool to see and its nice to learn something i have no idea about!
Two things I love about this channel, your ability to break down really complex programming concepts in to something easy to get my head around and the fact that your test and explainer side projects are damn near finished projects in their own right. Love it all!
The result is excellent, and the explanations are great. I think the key to sebastian's success is his attention to the small details. When he explains he may put a slight animation that you only see for 3 seconds in the video, but he has taken the time to prepare it carefully. That enhances the quality of an already 100/100 content. Thanks for taking the time to do the remaining 20% of things that enhance the content so much. Greetings from a big fan. Keep it up💪💪💪
This visualisation of the rays hitting the model and the BVH test at 8:50 is really quite awesome. Great videos, please continue Sebastian.
Tbh I really love your videos. Your voice always feels like you're enjoying every moment of the explanation. Not only it gives both coding knowledge but also inspiring for me to continue my coding journey. I think it does the same things for other people too. Thank you for posting those videos!
Really great job with switching to an array of index values for your stack and leaving the nodes alone in their own array! The reason this is much better is because primitive types like floats and ints are always copied since they're considered trivially copyable (i.e., they don't take much time to copy at all and the computer could do it in its sleep), but when you have a lot of them, that time adds up. Now instead of copying all of the node data each time new nodes are pushed and popped from the stack, only single integer values are copied, which reduces the overal number of copies by a lot. Additionally, arrays are constant-time lookup, meaning no matter how big an array gets, it will always take the same amount of time to access a value. This is because the index values are actually just memory offsets, meaning only a single addition and multiplication are needed to go from the start of an array to a particular element. This means that you ended up trading in the cost of a bunch of unnecessary copies for the constant-time lookup of the nodes. I definitely believed that result when I saw it! Also I'm glad to see you getting more detailed about how computers work! You actually optimized your code to prevent cache misses!
Your videos are so relaxing to watch, and your coding adventures cover all of the things I want to do, but simply don't have time for. I cannot appreciate enough the effort you put into these videos! Please keep them coming!
It's perfect timing. I’ve been diving into ray tracing concepts for about a year now, and it's impressive how you've managed to pull this off so quickly. Your video is inspiring and gives me some new ideas to explore. Keep up the great work! 👍
It's always great to watch a coding adventures video. I didn't know where the 50 minutes went by, your videos are always so interesting Sebastian!
I remember watching your previous Raytracing Videos like it was yesterday. Its always nice to see when you upload. Keep up the great content
It’s incredible how well you communicate complex ideas, thanks for your videos, excellent work
Honestly, I could watch your videos forever. Great visuals, great background music, great explanations and great concepts!
I love the speed and pacing you go over things. I find a LOT of programming/tech channels on youtube they just speak at an insane pace like they are gonna explode if they stop talking and makes it so hard to watch. Your videos? *chef's kiss*
Please keep making more coding adventure videos like this!
One thing that I love about your videos is (the fact that && how) you show the optimization process: you briefly explain the idea behind the changes in code, show the actual changes and my favorite part - show a chart that shows the quantization of how productive that change was. I love seeing charts like that, but the whole process is also very entertaining to follow. How you come up with all these different ideas and what difference they make, love it.
At 40:38 You have a struct that contains two float3s and two ints. If I'm remembering correctly, due to the byte alignment this will actually result in 48 bytes. because unfortunately float3s round up to 16 bytes for alignment and the 2 ints (due to the highest alignment in the struct being 16 bytes) will also take up 16 bytes. I'm not entirely sure how well you can do this, but you might try stuffing the 2 ints into each of the float3s to make two float4s. resulting in a true 32 byte node. Not 100% sure about how much better this is though.
That depends on what language is used. HLSL aligns StructuredBuffer tightly. So in this case no extra padding is added. If it was a cbuffer you'd be right or if it was GLSL. It is still a good idea to move the int before the other float3 though, as this won't have weird behavior if you do want to store it in a cbuffer somehow..
@@nielsbishere This "align up to 16 bytes" behavior is not required: the default setting of "shared" (and "packed", which is similar) leave all details up to the implementation. The option of "std140" does introduce this alignment, however, but the newer "std430" does not.
@@pitust yup. Ssbos with the correct layout are an exception indeed
@@pitust std430 does align float3 (or rather, vec3, which is the glsl variant) to 16 bytes. But it it doesn't have the 16 byte array stride that std140 has. For example:
float[4] -> in std140, this is "similar" to float4[4], in std430 it is stored tightly like a single float4
A similar rule exists for structs in std140, which std430 also gets rid of. But std430 still has the special alignment rule for vec3.
I really really love the humour, the in depth explanations, the animations, pretty much everything. It feels so relaxing and like you really care abt everything which makes it so enjoyable to watch
Half an eternity = 8 seconds
The Sebastian Lague theory
Incredible Video, I love the beautiful explantation cut-aways of all these complex and hard to grasp concepts that are easy understandable thanks to you. Great work :)
very nice video as always! I am implementing a simple raytracer in plain C right now as well, but i am using a simple grid instead of a BVH
I have watched you evolve your skills over the years and you have in front of me become a god. I started developing a bit before I found you on youtube 5-6 years ago and it's so fascinating to me to see you develop and also see me develop in the process. I love your videos and hope to see you for another 5-6 years making more amazing content like this.
21:11 ♫♪♫♪ I don't want to set the world on fire ♫♪♫♪
That’s exactly what I was thinking
"Hi Sebastian!
I’ve been following your content for a while, and your videos on procedural generation and game development are incredibly insightful. I’m working on a voxel-based game inspired by Minecraft, and I was wondering if you’d consider making a video that goes in-depth on voxel world generation, similar to how Minecraft does it. It would be amazing to see your take on chunk loading, terrain generation using noise functions, and optimization techniques for creating large worlds.
Your expertise and clear explanations would be incredibly helpful for many aspiring developers like me! Thanks for all the great content you’ve shared so far!"
Banger as always, thanks Sebastian!
HOLY DAMN THIS GUY BLEW UP.
Context, I watched this guylike 8 years ago(maybe more but it feels like 8, 20k followers thought he was underated af, actually had a chat with him briefly about how to reverse an algorithm for I think it was moving platforms, quite a shock to see him over 1 mill, its like seeing and old friend and being happy for their success, feels good :3.
Beautiful.
So satisfying, watching someone that can actually get shit done.
It would be fun to see you explore HDR buffers and HDR tone mapping for this series, or just color space stuff in general!
Whenever i see a new video released by Sebastian i just want to close off the rest of the world and enjoy it. Sebastian - I have no chance of ever being even a fraction as clever as you, but the way you explain things makes it really easy to follow and understand... Its such a great experience knowing that you will leave the video a little cleverer and more aware of things. The way you tackle problems and overcome them is really helpful. I cant wait to start implementing some aspects of these learnings into ideas i have.
Thanks for making the internet a better place with your videos!
To make the image less noisy you can look into reprojection. There is a great article made by Jacco Bikker (same guy who made the bvh article)
Or some simple a-svgf
I'm pretty sure that reprojection just allows for the reuse of render data from frames where the camera is in a different position, and doesn't actually decrease the amount of noise when the camera is static
@@user-dh8oi2mk4f For realtime previews it's very useful. For offline renders it doesn't reduce the noise. And in fact reprojection would add bias. For that, you should probably use ReSTIR (DI/GI/PT) or a spatial denoiser (adds bias though).
I can't even begin to explain how much joy your videos bring me
When choosing where to split based on the surface area huristic, you should do a binary search instead of checking 5 arbitrary splits along an axis
I don't think the surface area heuristic is monotonic with respect to the split position
@@user-dh8oi2mk4fUse linear interpolation / marching squares-esque to estimate it
Loved this video Sebastian! Keep up the great work. It's a complex topic but you always seem to break it down in such a way that I can follow along.
How about a kd-tree? It is a more efficient data structure for static scenes. It is so efficient because it can stop as soon as it intersects with something inside a bounding box, as it gives distance sorted boxes. The intersection math is also waay faster!
Build times and splitting triangles can be a problem there, but if it can be baked or is just for a demo it's a good option. It will also force you to build on the cpu
A quirk is that a triangle can't be split like that (well, it can, but it makes things more complex): a BVH can have each side overlap enough to get the triangles on each side fully contained. It's not a complete loss though, you can generally simply put the triangle on both sides of the tree.
This did not feel like an hour. Well done on the video 👏 Here's to hoping you continue on exploring more and more advanced raytracing topics. This kind of content is to die for.
HERE WE GOOOOO
As I learn more about programming I’ve started to realize just how much you are actually doing, you make it look so effortless I didn’t comprehend just how much you wave away with a quick sentence, when I was learning compute shaders I watched your earlier raycast videos and you explain everything so clearly while doing such complicated stuff, your videos are always so informative and have helped me learn a lot
that was a year or so ago??????????!!!
Apparently!
hi oziji
@@SebastianLague fruit flies, arrows, bananas, etc, you know how it goes.
I measure the passage of time by the coming and going of Sebastian Lague videos
I love how you explain code and shows us your little mistakes in there as well. It shows the natural thought process and shows that even you are human (even though you create these wonderful visualisations). Amazing work!
This might be very inefficient but I, as a person who doesn’t code, have an idea. What if the rays were emitted from the camera, meaning that you don’t have to render any rays that don’t make it to it?
he's already doing that, and it is efficient. though it is not so efficient in terms of finding rays that made it to light (it's reversed after all)
@stubman5927 luckily that's why NEE, MIS and gang exist. BDPT is also great if caustics are important
I love seeing how each change increases the performance, and how certain changes benefit (or require) other changes in order to actually bring a benefit.
I similarly loved watching the different operations of the chess bot play against each other.
Sebastian: uploads a video
*fifteen treseptagintilion years pass*
Sebastian: uploads a video
Edit1: no way I got 11 likes that’s never happened before!
Lel :P
>
Your videos about binary options trading are always very interesting and useful. I learned a lot of new things and learned to put them into practice.
21:13 Japanese citizens on august 6 of 1945:
Amazing work.
I appreciate your video format, straight to the point and concise. Keep up the good work! :D
This video is fucking AWESOME. You have such a talent for displaying these metrics, and it is so exciting to see the performance go up, to see the bounding boxes become more ghost-like as you're running all these tests... so cool.
I appreciate that you show what happens when you do something wrong. It helps with visualizing what is going on.
Some of those renders are absolutely gorgeous
I have done this in a class 2 years ago so I knew exactly what you were doing and still I watched a one hour long video just because the narrative and visualization are so well made. Thanks a lot for this!
Wonderful video as always! I recently saw a presentation by EA on how blue noise using the golden ratio is a huge improvement to perceived quality when rendering, since each pixel is randomized with respect to its neighbors rather than the full spectrum. This could speed up rendering by lowering the number of rays needed, and helps a lot with depth of field blurring which can look patchy at lower quality with white noise.
What's also neat is that blue noise applies to any pseudorandom function by making the frequency higher. Essentially, it makes the next roll related to the previous roll and allows the gambler's fallacy to no longer be false.
Right into my mental model you go. What an excellent explanation!
what always captivates me is the way you visualise everything, especially the debugging. My life would be so much easier if I went past print statements 90% of the time 😂
I woke up sick today and this is exactly what I need rn! Thank you!
it's crazy that right as i wondered about ray tracing this video showed up, you're so good at explaining this stuff.
Your videos make my day every single time. Good job, keep it up 👍👍
JUST today I was looking up how to build and work with a BVH. And now you drop a video on the topic. Thanks a bunch, man!
Wow! You're doing an amazing job at making tough topics accessibly understandable to a wider array of aspiring graphics programmers! I really appreciate what you're doing here.
It's always an international holiday for coders when Sebastian Lague uploads. Your videos are awesome!
I've never understood anything you've said, nor do I have an interest in coding but i keep coming back.
This Channel is really one of the best educational channels out there for this kind of topic. So much knowledge for free. Really good demonstration. Thanks for so much effort you definitely put into your videos
The experience of watching your videos while having dinner is so awesome. Thanks man, as a software developer I really appreciate all the work you've done with the audio, voice over, research, code and incremental changes 🤝
you dont understand how much of a saviour you are, 10/10 vid
You coding adventures are among my favorite videos.
Amazing work as always my dude. Love your content
HELL YEAH I LOVE VIDEOS OF CODING RAY TRACING
your presentation of the subject matter is the gold standard! the way you show how everything works and the highlighting of the code as you explain it 😗👌
This is, as always, incredibly interesting, motivating and soothing at the same time. Thank you for this.
You have a gift of uploading a video whenever I go back to your channel to rewatch a previous one. I'm sure I'm in for an hour long treat :D
Really relaxing, satisfying and interesting to watch
This is really a great video! I love how your editing got more visual-based rather than code-based, and it made the video riveting despite beeing nearly a hour long
Day's always great when a new Coding Adventure video comes out.
I can't wait to see all the probability light biasing stuff you mentioned.
It was one of my more favorite things when tinkering with ray tracing, and I think you'd do a MUCH better job explaining it than some words on a screen
Great video as always Sebastian
thank you sebastian, an absolute pleasure to watch
OMG YES I WAS SO LOOKING FORWARD TO THIS SPECIFIC VIDEO !!!! I made a raytracing engine because (or thanks to) you, you're an inspiration for coding and learning
Sebastian drops a new video, immediately clicked on it. That's defiantly a good investment of 50 minutes
You will not believe it if I said I've been watching your channel for over 4 years now and I have just realized today that your name is Sebastian *Lague* , always thought it was Sebastian *League* how have I not realized this
You know it's good when the youtuber pulls out the research paper. I love this channel so, so much. Makes me wanna go out and write some code just because how fun it makes it look!
Man i am here fast. And I just know this is going to be fun. You never disappoint
Yayaaaa its the best programming series on UA-cam