Rounding Corners in SDFs

[@ThaRemo]

3:20 that transition is so goood!

[@mactyler]

ThaRemo lol same i rewatched it like 5 times when it happened the first time through

[@aornelas]

yaaaas! i saw this as the teaser in the tweet (twitter.com/iquilezles/status/1191507589487415297) and couldn't help but watch the whole video -- even when this is the first time i hear about SDF 😆

[@collection6062]

jeezus christ that was to much

[@pronotron]

I need a couple of days to do it in blender, he is just using math

[@miketuritzin]

I am blown away by the quality of these videos! (as well as how well-explained everything is)

[@NonTwinBrothers]

I swear one day this channel will explode

[@sanjuro_493]

i love the lapsus at 1:29 when you said "older", i was thinking about counting trees' age too, lol.

[@iestynne]

Would love to see a video about the common difficulties you may encounter when using SDFs and how to work around them. For example the "metric distortion" that you mention occurs when perturbing a surface with noise. Or how the SDF of two touching boxes is different from the SDF of a box twice the width. That kind of thing.

[@abuelospelico8945]

Hola buenas tardes me volví con el que no te gusta en la casa de mi cumpleaños me volví a dormir mejor me volví con el lunes a las mejor no

[@edub4rt]

Wow, awesome, please keep doing these kind of videos. I've admired your work for years, you are a genius in this field, I feel that we could learn a lot of stuff from you that is hardly taught out there. Your skills and knowledge about mathematical graphics is truly in a unique level and inspires me to learn and work more on the topic.

[@Nolkaloid]

Just that intro music makes me have chills of excitement!

[@xbzq]

Holy cats. A+++. That's an amazingly high quality video, looks like it was produced by an entire agency or Pixar or DreamWorks. And it's just a KZbin video on a (yet) small channel. Hats off.

[@iaobardar3452]

I love your videos. They really click in my head, helping me understand the SDFs. I can't wait till the next one!

[@mactyler]

I work in computer graphics and you literally blow me away with every video. What an incredible abstraction to create anything you can imagine in such an efficient way

[@kylepena8908]

Inigo this is world class content

[@dgoberna]

wow man, the production effort you are investing in the new videos is amazing!! so profesional, neat and well done.. I'm sure it also takes a looot of time to make, how difficult may be to know where to draw the line :/

[@InigoQuilez]

Yes. I feel the ratio of visual sexyness to content is a bit off in this one - the VFX part was for example unnecessary. But fun. The solution is not lowering the visuals, but upping the depth of the content in the next videos.

[@xbzq]

@@InigoQuilez Well, I think that by throwing in this deep visual awesomeness, you're not just showing everyone what kind of math you can do, but _exactly_ what the results can be if you're willing to hang in there. It's the carrot to reach for. Also, you make it seem effortless with your calm voice that doesn't once yell out: "Check out this awesome thing!"

[@dgoberna]

@@InigoQuilez the VFX part was totally unexpected but utterly awesome! :D Same thing with the transition to the old columns scene, brutal. But wtf, you have fun and are happy, and we are watching quality content, learn, flip out and get inspired. What's the problem? Well, I guess problem is time and money, those little bastards :)

[@yaseenkhattak1845]

I just found Gold on the internet, Your explanations are so on spot !

[@TimMatthewsX]

As always, absolutely amazing Inigo! I've watched this a few times now, both for the content - which has really clarified the role of isolines in SDF - but also because it is incredibly beautiful! Making a useful tutorial that is also stand-alone art in its own right is wonderful

[@johnjackson9767]

It's a crime that these don't have more views.

[@MichaelProstka]

Brilliant! Been following your work for a few years, you are the Undisputed SDF Sensei!

[@KingCakeTheFruity]

Beautiful video! It really helped me understand what's going on. Smooth sdf connection is also quite an interesting thing to look at btw.

[@Nicoblabla]

The animations are so smooth ! Really nice video, thx

[@sanderbos4243]

Awesome, I now understand what makes SDFs so great!

[@batmansmk]

You went all out!! Congrats on the level of production. You have to tell me how you get such a good AR tracking.

[@dgoberna]

That's not AR, but traditional tracking, probably done with After Effects :)

[@o_o............]

@@dgoberna wtf

[@catafest-work]

good article ... depends of issues some objects with intersection can have an SDF (Signed Distance Field) after create ... or you can build them with SDF (Signed Distance Field) ... the optimization depends of this goal ...

[@Nicola5]

Great video! Explains and visuals is outstanding! Subscribed!

[@DoctorBabby]

Thanks for this very informative video! We're so used to polygonal rendering but alternative methods can be fascinating. Actually your name reminds me of something. Maybe I saw it before in a Blender or Shadertoy demo.

[@CAyou]

Hey man, awesome video! How do you handle the fact that the final result is not thicker? On all the example you show the base volume gets thicker. Thank you!

[@s3vdev]

That‘s what I thought. Missing this critical information - but love these explanations. Well done

[@dgoberna]

hahaha, I've just noticed the glitch effect on the titles (0:24) synched with the music. This must be the most demoscener tutorial ever :D

[@spencershrek1491]

Wow what!! This video quality is insane

[@NikolaNevenov86]

As a beginner I have one question. How do you preserve the size of the sdf after the rounding. Even in the video it was obvious that giving any value to "r" it rounds but also enlarges the field. Yet right in the beginning of the video, you had your rectangle have it's round edges while maintaining the same size.

[@InigoQuilez]

Yes, I forgot to mention that in the video, and I'll add it to a followup one. The basic idea is simple - make the source shape (box in the video) thinner by the same amount r, so after expansion the flat areas (no corners or edges) stay in place.

[@rationalistfaith]

Awesome! Triggering my passion for graphics programming again :)

[@RostamiMagic]

SUPER COOL!!!

[@dudewaldo4]

This is amazing work

[@kingreinhold9905]

So well done man! But I still got one question... Why do these models in the end not get thicker? Wouldn't the distance also be increased by r on the flat surfaces as described before?

[@kingreinhold9905]

I guess you just scale it down with the same technique first and by the same amount..

[@DanielStreck]

This video format is amazing!

[@brod515]

So that we keep the some size of the object It seems we should also adjust the actual SDF with r as well so the shape doesn't swell up.

[@sea-saw]

How do you make rounded corners on non-primitive shapes? For example, if I had a shape made of the intersection of two primitives, can I use this technique to round the corners of that shape?

[@InigoQuilez]

If you are computing the intersection with max(), then no, rounding won't work because intersections computed with max() don't produce euclidean distance fields, just bounds. That's the reason I try to derive the exact SDF of as many primitives as possible from first principles and not as the intersection of other primitives. See at the bottom of this list for example for exact SDFs that could have been approximated as booleans operations but I don't: iquilezles.org/www/articles/distfunctions2d/distfunctions2d.htm

[@andrevenancio]

Love your videos. Its really helpful for newcomers!

[@TokisanGames]

Wow, this is so amazing! I really appreciate the explanations and pacing.

[@codingislove3707]

thanks for the amazing explantations. One thing I don't understand why that is is why do the isosurfaces become rounder when moving away from the origin of the shape., and why are they round in the first place? what is the cause, mathematically? Sorry, I am a newb :)

[@geofftnz]

Great video iq! Keep them coming!

[@nano_redstone]

As always your content is really interesting! I alway's learn quite a bit keep up the good work !

[@breakingkeyboards]

Your work is always impressive!

[@SpeedyPainterSoftware]

man, you are amazing

[@neur303]

Impressive! Thank you Inigo :) It makes it so clear what is going on with all these functions :)

[@nrosquist]

fantastic videos. why do the isolines get rounder the further away you get? Is it a floating point rounding thing?

[@InigoQuilez]

No. that's the geometry of distance. The isolines _must_ be rounded to be an Euclidean distance. Think how the distance to a point is a set of concentric circles, so the distance to a corner, which is a point, must have arcs of such circles.

[@nrosquist]

@@InigoQuilez Ah thank you, very clear!

[@sharathchandra6166]

great channel i love your explanations!

[@alejmc]

Excellent video, explanation and music of choice! Unrelated but if possible, what’s the song? Thanks to this just started listening to Khrome but can’t find the one on this video (just listened to the ‘Absolute’ album)

[@InigoQuilez]

I commissioned the score to Khrome!

[@gamertech4589]

Do you have hls code or gls? Which can help manipulate it? Or link to ur webpage😅

[@mactyler]

Steppin on the scene like 💯 💯

[@arodic]

Amazing work Inigo!

[@InigoQuilez]

Thanks Aki!

[@fonzjedelarosa7587]

Excellent!

[@pantsoff]

Dude... please, more!

[@GoatMen]

What software do you use to make the 3d art in these videos?

[@ac12484]

Genius!!! Thanks!

[@Exoclypse]

Awesome video but I was wondering how do you apply transforms on the edges only and not the entire surface? Do you get the distance between the rounded SDF and the unrounded SDF as a mask?

[@InigoQuilez]

No. I think of it in two steps: 1. First, shrink the box dimensions by the same amount that you expect to inflate it through roundness. Since these two adjustments are equal in strength, let's call both the amount of roundness and shrinking R. This keeps the extents of the box unchanged and the volume approximately the same, but you got your roundness. That's because non-corners/edge parts of the surface recede as much during shrinking (R) as they advance during inflating (also R). However edges recede by an amount bigger than the shrinking amount R, for example sqrt(2)*R in thr case of a 90 degree angled edge. Corners move away from their original position about sqrt(3)*R. However when we inflate them back we are still inflating them by R. So, flat areas of the surface don't move, but edges and corners do move inwards (by an amount R(sqrt(2)-1) and R(sqrt(3)-1) in our examples). Which is what we want. 2. Second, we modulate R with the desired noise or pattern we want to give us R*M. In the areas were shrinking and roundness compensate exactly (the non-edges of our object) the modulation has no practical effect since we are still schrinkimg and inflating by R*M equally. But in the edge/corners, where rounding happened, the modulation still affects the net carving, since we get R*M*(sqrt(2)-1) of it in the edges. 3. Last, the modulation will break the global SDF metric, but you can dampen it easily. I'll try to cover this in a video.

[@Exoclypse]

@@InigoQuilez Oh I see, that's definitely smarter, thank you!

[@bigolol]

this is so incredibly good holy fucking shit

[@gillian6792]

We want a tutorial or at least some clue of how you do augmented reality with sdf ! thx and love for everyone

[@coolfunmario]

Hi IQ, you have a beautiful mind and a lot of unique knowledge and programming skill on some very technical topics which seem hidden or even a kind of witchcraft for the most part ( average|common developers ). You should start raising a crowdfunding or investigating other money resources then announcing an important educational project ( book, etc. ) and making it publicly visible for the most. I am pretty sure that you will attract of lot of momentum from people interested in graphics, CGI, video games making, etc. ( the resulting interactive pictures from shaders are stunning ) but actually kept away due to the technical entry level and that arcane stuff|skill requirements. Your resulting work will be your own bible and a testimony|memorial for the humankind, to improve it. Anyway, keep up the good work.

[@alijayameilio]

This is some extreme quality video XD

[@GeoffPlitt]

What tools did you use to match-move and composite the video footage with your render?

[@InigoQuilez]

I connect Shadertoy to After Effects with a custom plugin I wrote.

[@GeoffPlitt]

So cool :)

[@dgoberna]

@@InigoQuilez LOL

[@MichaelPohoreski]

Inigo Quilez Put that bad boy up on GitHub!

[@GeoffPlitt]

+1

[@starburstdragon]

Amazing as always - i like video before i watch it :)

[@dark808bb8]

great vid !

[@gamertech4589]

Where get code for this😅

[@ac12484]

Could you explain please what “breaking the metric” means (if you didn’t later, I continue to watch)

[@themrpancake]

3:08 lenght

[@bukebeyond]

This man is a true genius of 2020. He should be running Nvidia, Google, Facebook, Microsoft, Apple, Tesla as opposed to the stock salespeople.

[@themerpheus]

Awesome!

[@kupnitz]

thanks

[@rendermanpro]

awesome!

[@o_o............]

2:56 banned for nudity: i challenge you youtube!

[@zbl2550]

very cool...

[@delgilchrist]

great video :) keep it up!

[@chucktrier]

I love it

[@Lucas72928]

Doesn't the shape get bigger when you round it? Because you're using a bigger isosurface

[@InigoQuilez]

Yes it does. But you can made the "seed" object (the box in this case) smaller by the same amount, so keeping it's bounds constant. I know I should have say it explicitly in the video, my bad.

[@SinanAkkoyun]

So basically you are programming the object into the shader itself, right?

[@InigoQuilez]

Yes

[@PixelPulse168]

I wish youtube can have more thumbs-up buttons.

[@maxenceveilleux]

So... was I watching a Marvel movie? The VFX blew my mind!

[@InigoQuilez]

I got a bit carried away on this one :)

[@amelavnyt]

​@InigoQuilez No, it was awesome! We need more people like you

[@konstantinbondarenko5235]

super

[@richardramirez5746]

unbelievable...

[@yellowduckgamedev]

how tf does one UV map SDF objects?

[@InigoQuilez]

Generally, you don't!

[@4arliEdinorog]

Очень интересно и круто

[@dimidrolhalitovich5241]

i was looking for this in unreal! cos i use ofen fake chamfer in 3ds max

[@andrea9015]

1:29 hahaha I understood that reference

[@InigoQuilez]

Hehe

[@omgomgomgd]

lenght != length whoops.

[@Т1000-м1и]

11 months ago

[@adammajewski6381]

SDF = Signed Distance Functions

[@ffncfhf9745]

I scs

[@朏]

just random letters