Loading video...

Video Failed to Load

There was a problem loading this video. This could be due to a temporary network issue or the video might be unavailable.

Visualizing light paths differentials (actually, ray footprint / spread in this case). These are used in path tracing to compute texture filtering, among other things... and are too easy to botch in corner cases, resulting in bugs and performance issues that are hard to pin back to the cause.... show more

Max Liani

15,043 subscribers

39,160 views • 2 years ago •via X (Twitter)

Education Arts Science & Technology

Anya Rossi• Live Now

Private livecam show

9 Comments

Rhys2 years ago

This is so cool Max.

Max Liani2 years ago

🙏 I am trying to get back in the rhythm.

SimonA2 years ago

Great to see you are back on workbench 😁

𝘛𝘩𝘪𝘣𝘢𝘶𝘭𝘵 ➡️ 🦋 | 🐘2 years ago

Quick question about the ray "replay": do you actually store the "hit tree" for all pixels or do you re-compute it when requested ? If you store it, I'd be interested to see how large it is in memory!

Max Liani2 years ago

I recompute the exact same paths of the selected pixel with the instrumented version of the integrator kernel. Doing it for the whole image would be GBs and likely wouldn’t fit in memory. The way I do it I can store abundant information per path vertex without much to worry.

Mauricio2 years ago

Ship it.

IB2 years ago

How do you account for the BRDF and surface roughness when computing spread?

Max Liani2 years ago

Integrators tend to be implemented to sample solid angles. The solid angle of a cone half angle is: Ω = 2 π(1-cos θ) The probability density of sampling a BRDF is to a factor reciprocal to the sampled solid angle. You probably need to clamp the pdf for values lower than 1. This is an approximation, but a reasonable starting point.

kane NVC2 years ago

Cool and practical work, the elusive lighting makes it concrete

Related Videos

I am expanding what the pixel inspector can do, now capturing and visualizing light paths contributing to the pixel. The scattered paths are in yellow, NEE in red.

I am expanding what the pixel inspector can do, now capturing and visualizing light paths contributing to the pixel. The scattered paths are in yellow, NEE in red.

Max Liani

87,458 views • 3 years ago

Really cool to see a lot of different elements in play here during his ‘Velocity Training’. The ability to weave these things together coherently in a case-by-case basis is what allows athletes to progress faster and faster in terms of developing skills that actually transfer.

Really cool to see a lot of different elements in play here during his ‘Velocity Training’. The ability to weave these things together coherently in a case-by-case basis is what allows athletes to progress faster and faster in terms of developing skills that actually transfer.

Ben Baggett

58,071 views • 2 years ago

How cool are these?! In Liverpool right now and I think these vintage Police cars and vans are to star in the new Sam Mendes film of The Beatles. I may be wrong of course, but I’ve never known that to happen.

How cool are these?! In Liverpool right now and I think these vintage Police cars and vans are to star in the new Sam Mendes film of The Beatles. I may be wrong of course, but I’ve never known that to happen.

Alastair Hilton

49,945 views • 1 month ago

His Beatitude Pierbattista Cardinal Pizzaballa, addressing Christians in Bethlehem today says “the light of Bethlehem is the Light of the World”, adding that “I saw in Gaza disaster there, the situation is really catastrophic, but I saw there also the desire for life”: “Dear friends, brothers and sisters, Merry Christmas! Today I see in Bethlehem is real Christmas! And today you are giving not just to Bethlehem, or the Holy Land, but to the whole world, what is the meaning of Christmas; I’m sure we are not out of all the problems, but today in Bethlehem I see light. Not just the sun, but you the people, I see the light, you are light, we all together are the light, because you decided to be the light. And the light of Bethlehem is the Light of the World. I bring to you the greetings, the prayers, and hugs, of our brothers and sisters in Gaza. I saw in Gaza disaster there, the situation is really catastrophic, but I saw there also the desire for life. In the midst of nothing they have been able to celebrate with joy despite everything, and they remind us that it is always possible to rebuild even in all the devastation we are seeing. So it is possible once again to celebrate in Gaza, it is possible to celebrate in Bethlehem, we need to celebrate not just today but everyday. We will rebuild everything, but we build within life and today I saw life. Merry Christmas!”

His Beatitude Pierbattista Cardinal Pizzaballa, addressing Christians in Bethlehem today says “the light of Bethlehem is the Light of the World”, adding that “I saw in Gaza disaster there, the situation is really catastrophic, but I saw there also the desire for life”: “Dear friends, brothers and sisters, Merry Christmas! Today I see in Bethlehem is real Christmas! And today you are giving not just to Bethlehem, or the Holy Land, but to the whole world, what is the meaning of Christmas; I’m sure we are not out of all the problems, but today in Bethlehem I see light. Not just the sun, but you the people, I see the light, you are light, we all together are the light, because you decided to be the light. And the light of Bethlehem is the Light of the World. I bring to you the greetings, the prayers, and hugs, of our brothers and sisters in Gaza. I saw in Gaza disaster there, the situation is really catastrophic, but I saw there also the desire for life. In the midst of nothing they have been able to celebrate with joy despite everything, and they remind us that it is always possible to rebuild even in all the devastation we are seeing. So it is possible once again to celebrate in Gaza, it is possible to celebrate in Bethlehem, we need to celebrate not just today but everyday. We will rebuild everything, but we build within life and today I saw life. Merry Christmas!”

Catholic Sat

62,905 views • 10 months ago

It's the time of year to spread some seasonal scare, and we've got some new treats to help you trick! Check out the range of new seasonal Halloween microtransactions in this video. These are available in both Path of Exile 1 and Path of Exile 2.

It's the time of year to spread some seasonal scare, and we've got some new treats to help you trick! Check out the range of new seasonal Halloween microtransactions in this video. These are available in both Path of Exile 1 and Path of Exile 2.

Path of Exile

118,448 views • 1 year ago

THE SUN US OUR FOOD The Sun is Electric and the Earth is Magnetic. We are Electromagnetic beings. Learn how to operate in this realm. The fundamental truth is that you are the light you are seeking. You are already enlightened, as your biological reality is that you are a being of light, down to your DNA, your cells, and the trillions of biophotons that permeate your entire being. Even your bones, the densest part of your physical being, are piezoelectric crystalline structures that make electricity (light) when they are compressed. And this light that powers you is the same light that powers the Sun and the Stars, the lightning and the lightning bugs, and the Cosmos in its entirety. We are electromagnetic beings bathed in an electrically connected reality. You are vast. You contain multitudes. What has been obstructing that knowing and being is just a story; distorted waves in space that can be tuned back to their underlying harmonious perfection. Beneath the noise in the signal and stories of victimhood and struggle, you are simply one with the Unified Field, the Cosmos Itself - YOU are the UNIVERSE. And from that perspective everything is possible. ✨🙌🏾💫 © The Path to Enlightenment

THE SUN US OUR FOOD The Sun is Electric and the Earth is Magnetic. We are Electromagnetic beings. Learn how to operate in this realm. The fundamental truth is that you are the light you are seeking. You are already enlightened, as your biological reality is that you are a being of light, down to your DNA, your cells, and the trillions of biophotons that permeate your entire being. Even your bones, the densest part of your physical being, are piezoelectric crystalline structures that make electricity (light) when they are compressed. And this light that powers you is the same light that powers the Sun and the Stars, the lightning and the lightning bugs, and the Cosmos in its entirety. We are electromagnetic beings bathed in an electrically connected reality. You are vast. You contain multitudes. What has been obstructing that knowing and being is just a story; distorted waves in space that can be tuned back to their underlying harmonious perfection. Beneath the noise in the signal and stories of victimhood and struggle, you are simply one with the Unified Field, the Cosmos Itself - YOU are the UNIVERSE. And from that perspective everything is possible. ✨🙌🏾💫 © The Path to Enlightenment

🧬Maxpein🧬

100,247 views • 1 year ago

Nikki Haley talks straight to the camera in a powerful moment: “I genuinely hope that he will go out to the 20% of people that are going to decide this election and say: I need your vote and I’m going to fight hard to do it and these are the issues I’m going to fight on.”

Nikki Haley talks straight to the camera in a powerful moment: “I genuinely hope that he will go out to the 20% of people that are going to decide this election and say: I need your vote and I’m going to fight hard to do it and these are the issues I’m going to fight on.”

Nikki Haley HQ

106,077 views • 2 years ago

Turn off the light, look in the mirror. I See the Angels visualizer out now. I see a lot more cruelty in the world these days, and I think the true angels in our reality are the people who overcome cruelness and judgement. They're people who lift others up and don't try to conquer each other; they’re more accepting and loving of who each other are. I do see angels among us, truly clear as day. I see the people who are fighting for the world to be a good place and I see the people who overcome darkness every day to help others, and make the world prevail in goodness. This song is about those people 🤍

Turn off the light, look in the mirror. I See the Angels visualizer out now. I see a lot more cruelty in the world these days, and I think the true angels in our reality are the people who overcome cruelness and judgement. They're people who lift others up and don't try to conquer each other; they’re more accepting and loving of who each other are. I do see angels among us, truly clear as day. I see the people who are fighting for the world to be a good place and I see the people who overcome darkness every day to help others, and make the world prevail in goodness. This song is about those people 🤍

Ashton Irwin

87,345 views • 2 years ago

"This is where Mamdani is a model...There's this narrative that what Democrats have to do in order to win is to take squishy middle positions on everything. I actually disagree with that assessment. I think it's absolutely possible to take almost any position you want. There are kind of two things that are important though: You can't let niche issues that are not the primary concerns of a lot of voters dominate the messaging & the campaign. You need to stay the most focused on what voters actually care about." Musa al-Gharbi

"This is where Mamdani is a model...There's this narrative that what Democrats have to do in order to win is to take squishy middle positions on everything. I actually disagree with that assessment. I think it's absolutely possible to take almost any position you want. There are kind of two things that are important though: You can't let niche issues that are not the primary concerns of a lot of voters dominate the messaging & the campaign. You need to stay the most focused on what voters actually care about." Musa al-Gharbi

Briahna Joy Gray

24,457 views • 3 months ago

I tested out how The RX 9070 XT handles Path Tracing in Witcher 3 Remastered and it runs surprisingly well at 4K external resolution (FSR Performance and Frame-gen enabled) I'm definitely not going to play the game this way as the visual differences between Ray Tracing Ultra and Path Tracing are not that visible but if anyone has been wondering if it is possible to play the game like this, it certainly is. AMD 26.9.2 driver has just been released and The Witcher 3 Remastered graphical issues and artifacts have been fixed.

I tested out how The RX 9070 XT handles Path Tracing in Witcher 3 Remastered and it runs surprisingly well at 4K external resolution (FSR Performance and Frame-gen enabled) I'm definitely not going to play the game this way as the visual differences between Ray Tracing Ultra and Path Tracing are not that visible but if anyone has been wondering if it is possible to play the game like this, it certainly is. AMD 26.9.2 driver has just been released and The Witcher 3 Remastered graphical issues and artifacts have been fixed.

NikTek

18,741 views • 27 days ago

Elon Musk: Do we want to be in many worlds, or forever confined to Earth? “There are so many things to worry about, so many things to be concerned about. There are many troubles in the world, of course, and these are important, and we need to solve them. But we also need things that make us excited to be alive, that make us glad to wake up in the morning and be fired up about the future and think the future is going to be great. Space exploration is one of those things. Becoming a space-faring civilization, being out there among the stars, this is one of the things that I know makes me glad to be alive. I think it makes many people glad to be alive. It's one of the best things. Really, we're faced with a choice: Which future do you want? Do you want a future where we become a space-faring civilization and are in many worlds and are out there among the stars, or one where we are forever confined to Earth? I say it is the first. And I hope you agree with me.” Starship Update, September 2019

Elon Musk: Do we want to be in many worlds, or forever confined to Earth? “There are so many things to worry about, so many things to be concerned about. There are many troubles in the world, of course, and these are important, and we need to solve them. But we also need things that make us excited to be alive, that make us glad to wake up in the morning and be fired up about the future and think the future is going to be great. Space exploration is one of those things. Becoming a space-faring civilization, being out there among the stars, this is one of the things that I know makes me glad to be alive. I think it makes many people glad to be alive. It's one of the best things. Really, we're faced with a choice: Which future do you want? Do you want a future where we become a space-faring civilization and are in many worlds and are out there among the stars, or one where we are forever confined to Earth? I say it is the first. And I hope you agree with me.” Starship Update, September 2019

ELON CLIPS

1,684,317 views • 1 year ago

Ana Valens talks about leftoids in the vtubing scene. Here are some choice quotes if you don't want to sit through 10 minutes of this. "I think Nyara and Bint both have a philosophy that is really important to make allies in the vtubing world for lefty stuff. So they have created frameworks to talk about issues to make themselves palpable to centrists." "I also identified what battles I pick. That I need to ally myself with different kinds of people in vtubing, that I need to be diplomatic and not like um... It's important for someone like myself to try to find ways to appeal to in the middle space." "Trying to convince people in the Phase community that are like left off center that there is actually a path where we can say ""I love Pipkin Pippa but it's also important that someone is not like racist"", which lo and behold is actually happening."

Sensitive content

Ana Valens talks about leftoids in the vtubing scene. Here are some choice quotes if you don't want to sit through 10 minutes of this. "I think Nyara and Bint both have a philosophy that is really important to make allies in the vtubing world for lefty stuff. So they have created frameworks to talk about issues to make themselves palpable to centrists." "I also identified what battles I pick. That I need to ally myself with different kinds of people in vtubing, that I need to be diplomatic and not like um... It's important for someone like myself to try to find ways to appeal to in the middle space." "Trying to convince people in the Phase community that are like left off center that there is actually a path where we can say ""I love Pipkin Pippa but it's also important that someone is not like racist"", which lo and behold is actually happening."

Kuri Rinji's VTuber & Fan Cringe/Drama🌰

64,927 views • 8 months ago

“These are Jewish families and Jewish settlements arriving in Male’ area. Which of the countries with the greatest influence over the Maldives stand closest to Israel? Think about that. That is how alarming this is and what a threat it poses to the Maldives” - YAG #EagleHillsOut

“These are Jewish families and Jewish settlements arriving in Male’ area. Which of the countries with the greatest influence over the Maldives stand closest to Israel? Think about that. That is how alarming this is and what a threat it poses to the Maldives” - YAG #EagleHillsOut

Hassan Kurusee

28,701 views • 29 days ago

Chamath Palihapitiya on SpaceX today: "I think it’s an incredible company. I really believe in Elon Musk . I believe in SpaceX. I think that people are probably underestimating the short-term value of two things. One is the industrial logic of acquiring Tesla. There is a very obvious industrial logic to put these two businesses together, to have one capital structure, to have one balance sheet, to be able to raise money for the broad swath of things that he’s doing as one vehicle. And then the second is I think that you’re going to see an enormous business in the domestic cellular market before you see a lot of other revenue streams hit."

Chamath Palihapitiya on SpaceX today: "I think it’s an incredible company. I really believe in Elon Musk . I believe in SpaceX. I think that people are probably underestimating the short-term value of two things. One is the industrial logic of acquiring Tesla. There is a very obvious industrial logic to put these two businesses together, to have one capital structure, to have one balance sheet, to be able to raise money for the broad swath of things that he’s doing as one vehicle. And then the second is I think that you’re going to see an enormous business in the domestic cellular market before you see a lot of other revenue streams hit."

DogeDesigner

228,801 views • 3 months ago

Pope Leo XIV sends a heart felt video message to young Catholics in Iraq: “It is not always easy to be a light in the world. Indeed, at the present time, you are called to radiate this light in a situation that has often been marked by war and instability. The Lord has placed great trust in you in bestowing upon you this mission, and I too have great confidence in all of you. You must be Christ’s light in the midst of a darkness that can, at times, seem overwhelming. Do not be afraid! And do not think that you are alone in this task. I am with you; the Church is with you. Place your trust in Jesus; listen to him in prayer and through the guidance of others, and allow him to lead you.”

Pope Leo XIV sends a heart felt video message to young Catholics in Iraq: “It is not always easy to be a light in the world. Indeed, at the present time, you are called to radiate this light in a situation that has often been marked by war and instability. The Lord has placed great trust in you in bestowing upon you this mission, and I too have great confidence in all of you. You must be Christ’s light in the midst of a darkness that can, at times, seem overwhelming. Do not be afraid! And do not think that you are alone in this task. I am with you; the Church is with you. Place your trust in Jesus; listen to him in prayer and through the guidance of others, and allow him to lead you.”

Catholic Sat

23,099 views • 3 months ago

What do you think of in course out of bounds stakes? OCM added a boundary fence to Medinah that is out of bounds. It’s very much in play on 3 holes. With the Presidents Cup coming to Medinah, we get to see the first look at OCM’s amazing renovation work. I hope that these fences will come into play. Boundary out of bounds are pretty common in the UK, but generally in the USA out of bounds is frowned upon when man made and not an actual property line. I think it’s a brilliant idea! I wouldn’t want it to be used too often, but its limited use is great to add strategy and variety.

What do you think of in course out of bounds stakes? OCM added a boundary fence to Medinah that is out of bounds. It’s very much in play on 3 holes. With the Presidents Cup coming to Medinah, we get to see the first look at OCM’s amazing renovation work. I hope that these fences will come into play. Boundary out of bounds are pretty common in the UK, but generally in the USA out of bounds is frowned upon when man made and not an actual property line. I think it’s a brilliant idea! I wouldn’t want it to be used too often, but its limited use is great to add strategy and variety.

Rick Golfs

89,704 views • 1 month ago

NYU Stern researcher Nathan Witkin calls out a blind spot in AI alignment: "My point is that maybe to a degree that they don't often appreciate and in my opinion don't signal enough humility about, those risk scenarios are still highly dependent on domain knowledge in other areas related to cyber risk and cybersecurity." "All of the different alignment-related arguments for extreme risk, they all path through other domains. They path through cyber risks, they path through bio risk. It's telling that you see this very consistent pattern where the domain experts are pretty much always more cautiously optimistic or at least only very modestly pessimistic than folks in AI alignment are." "I tend to think that is a negative signal about the rigor of a lot of the work going on in alignment personally. I'd expect the folks who have the domain knowledge to be low to the ground enough to be able to assess the feasibility of the sort of high-risk catastrophe scenarios. It's telling in my mind that there's a disconnect there." NYU Stern

NYU Stern researcher Nathan Witkin calls out a blind spot in AI alignment: "My point is that maybe to a degree that they don't often appreciate and in my opinion don't signal enough humility about, those risk scenarios are still highly dependent on domain knowledge in other areas related to cyber risk and cybersecurity." "All of the different alignment-related arguments for extreme risk, they all path through other domains. They path through cyber risks, they path through bio risk. It's telling that you see this very consistent pattern where the domain experts are pretty much always more cautiously optimistic or at least only very modestly pessimistic than folks in AI alignment are." "I tend to think that is a negative signal about the rigor of a lot of the work going on in alignment personally. I'd expect the folks who have the domain knowledge to be low to the ground enough to be able to assess the feasibility of the sort of high-risk catastrophe scenarios. It's telling in my mind that there's a disconnect there." NYU Stern

MTS

14,469 views • 1 month ago

Asmongold responds after WoW Forever players call for his ban over claims that his massive guild “Olympus” is causing too many issues 😳 "I would like to address the allegations.. They're true.. There are two groups of people in WoW Forever.. There are the people who are in Olympus and the people who aren't in Olympus yet." "A lot of the people that are mad about me are fat in real life.. They are used to getting their way by being fat.. So many snowflakes.. I'm glad to see people pushing back on this."

Asmongold responds after WoW Forever players call for his ban over claims that his massive guild “Olympus” is causing too many issues 😳 "I would like to address the allegations.. They're true.. There are two groups of people in WoW Forever.. There are the people who are in Olympus and the people who aren't in Olympus yet." "A lot of the people that are mad about me are fat in real life.. They are used to getting their way by being fat.. So many snowflakes.. I'm glad to see people pushing back on this."

bloom 𖧧

578,684 views • 1 month ago