Impossible triangles

Exploring some ways to create the illusion of an impossible triangle.
Impossible triangle (helix):
shpws.me/TggA
www.printables.com/model/2921...
tato_713's "Penrose triangle like figure"
www.printables.com/model/1574...
Impossible triangle (tilted planes):
shpws.me/TggB
www.printables.com/model/2921...

[@sylphofspace2258]

Fun fact: an extremely similar version of this shape, which uses perspective to make it look impossible, can be seen in the title screen of Super Mario 3D Land on the 3DS of all things! It was made to show off the capabilities of the handheld's 3D slider functionality. With the slider off, the shape appears to be impossible, but with the slider on, the player can see where the cut is made using depth made possible by 3D.

[@bugglemagnum6213]

the 3ds of all things!!!! you dont say, one of the only successful devices with perspective 3d shows you shapes in 3d, reddit npc ass comment

[@augustdeer]

I don't see anything like this on the title screen, and I can't find any mention of this anywhere else. Do you have a source?

[@hoo2042]

@@augustdeer The description above wasn’t super clear. It’s not the static title screen but rather part of the demo that plays if you leave the game on the title screen for long enough: kzbin.info/www/bejne/h4eTqWyho7GhhqM

[@lorenzoblum868]

Product placement

[@TheInvisibleCactusYT]

This is one of the best real life impossible triangles I’ve ever seen Absolutely amazing content as always!

[@PeterBarnes2]

I feel like some kind of compromise between tato's curved version and your edge-cheat version might be interesting, with the curves allowing the edges to have much less cheating, while the edge-cheating allows the curvature to be much more subtle. That and making it optimized for one particular perspective might yield results more resilient to lighting, though perhaps not as convincing as this. Of course, I don't have the brain power to visualize what I'm talking about, so perhaps this doesn't amount to much of an idea.

[@composaboi]

I have given you your 100th like. Congrats.

[@nunyobidness993]

@@composaboi Why is reaching an arbitrary threshold of fake internet points something worthy of congratulations?

[@composaboi]

@@nunyobidness993 how is it arbitrary? If it makes one happy, I think it’s congratulatory.

[@composaboi]

@@nunyobidness993 also, why are you salty? I’m just trying to make someone’s day. Is there some problem with it? The only thing I can think is that it’s personal. Are you jealous that he got congratulated? If so, congratulations for being the biggest douche I’ve encountered today. Have a good day.

[@caramelapple5562]

@@nunyobidness993 why not?

[@michaeldeierhoi4096]

I could never have imagined such a detailed analysis of this optical illusion not could I have guessed the interesting 3-D alternative to the Penrose triangle at 2:40. Thanks for this different look at it.

[@shaun138]

One of the most underrated science communication channels out there.

[@Rubrickety]

That's a really nice implementation. I hadn't seen it before; is it original? I like the fact that, even after you know the construction, the shot at 4:08 where you move your finger between two "adjacent" faces is quite startling.

[@henryseg]

Lots of people have done the "put a cut somewhere" version, although I think that most of them use an orthogonal projection. Or at least, I don't know of another version that uses a perspective projection.

[@graxtheswampgoblinarchmage5356]

They actually did something similar in the movie inception as well

[@iconoclast137]

@•Lxl' Pxstel• is this school in some sort of utopian paradise?

[@danielstatler954]

Great content. Nothing is more wholesome than someone making a project about something they want to talk about without any need for reward other than the entertainment of the viewer. Got me through 5 minutes of physical pain 👍

[@StickySli]

This can totally be a museum's art piece. Brilliant!

[@KaiCyreus]

yay, not private!

[@henryseg]

Had to fix an audio problem with the previous upload!

[@trevise684]

Was fully expecting after "so this model is cheating somehow" for you to say "Well, actually this model is completely accurate to the design" and then go on to explain how you broke the universe

[@henryseg]

Yes, that would have made for a better video...

[@CamerTheDragon]

lmao, they're saving that for another vid of course

[@leif1075]

@@henryseg Thank you for sharing Henry. I really hope you can respond to my email or other message when you can. Thanks very much!!

[@AmaroqStarwind]

When you revealed which face was distorted at 3:07, I was actually thinking it was at the top corner because the lighting seemed a bit off there.

[@qv81]

I was sure there is a cut at the top peak to the left.. You can see a line there. The ending got me off guard. Good jib.

[@veggiedragon1000]

I knew the trick beforehand, but this was still interesting! My university had a large, metal sculpture that worked similarly to this, though a slightly different design.

[@VagabondTE]

Excellent job. I was trying to find the line and I didn't even get close.

[@dd884e5d8a]

Amazing and very well recorded!

[@jamoR72]

Unbelievably clever!

[@KiemPlant]

I always drew these ones at school. Every test had my signature penrose triangle on it lol.

[@gusty7153]

the best version of this triangle ive seen was from the videogame antichamber. it actualy spun around so it was almost perfect with only a barely noticable curvatute on the faces since the corners and lines were still very straight. looking at it from the side revealed that none of thr angles were actually right angles and the shape was overall compressed

[@StruckDuck]

Incredible video and beautifully explained! These illusions remind me that perspective is everything! If you are faced with a seemingly impossible problem, try changing your perspective and you’ll be surprised how many different solutions you can find!

[@liliwheeler2204]

1:39 I know I've found a good video when I have to stop halfway through to go find myself some props I actually tried to build one of these as a kid, after seeing it in a children's museum with a caption saying something like "This is impossible to build in real life, so if you make one, we'd love to see it!" It kind of worked, but the craft foam and tape I was using wasn't the most suitable material.... I seem to recall there was some kind of hidden mobius-loop-esque twist at the back

[@qazer10]

Pure art! Amazing

[@fCauneau]

Nice nice Art Work !! Thanks so much for sharing ! And Thanks also for the name of the true inventor of impossible triangle. NB for info. the law for the sociological phenomenon that states that most of inventors names are misplaced is called "Stiegler's Law" (and of course, this law is not due to Stiegler ;-)

[@defeatSpace]

This thing is cursed no matter which angle you view it from.

[@janjanjul]

Very cool demonstration.

[@dylanparker130]

Nicely done. I must confess that my favourite design was the one seen at 2:51. It felt like the most elegant, but utility must come first.

[@SOBIESKI_freedom]

Could the Penrose triangle exist natively as itself in Nil space?

[@henryseg]

Yes: kzbin.info/www/bejne/j56pdZdqbrymqLs

[@lydianlights]

wow I'd never heard of nil space but now I'm intrigued

[@Tanoaproductionsfiji]

My mind is blown! Thank you!! 🤯

[@fe4000]

Great lesson in geometry and photography at the same time.

[@lostiljon]

Very impressive, good job. I don't think I've seen one as good in 3d.

[@benjaminshields9421]

This video is gonna hit a million

[@DavidG2P]

Best one I've ever seen!

[@antzpantz]

We have a giant impossible triangle in the middle of a roundabout in East Perth, Australia!

[@Owl90]

That is pretty good!

[@abdulrockman3992]

Amazing!, great work

[@mazmuz987]

Everybody: "Impossible triangle" Me: "SMADAV triangle"

[@agoodun]

Very cool 😎

[@CamerTheDragon]

Ey nice vid and thx for the audio fix 😎👍

[@amadine770]

Quite believable regardless.

[@ChacUayabXoc]

Did you specifically account for the perspective distortion though with a specific focal length of the camera? or is it just "orthographically" designed and just works anyways?

[@henryseg]

I assumed a perspective view with the rays converging 25cm from the center of the object. I don't have a good understanding of how camera lenses work, so I wasn't sure that it would work well, but it seemed good enough. I guess that the lenses are designed to do as little distortion to the image as possible.

[@cozygameplayz5224]

Thank you !

[@IqweoR]

Impressive

[@sirwilliamkarl5591]

Cool!

[@bob2859]

How does one go about designing one of these models? I can't think how to accomplish this in CAD...

[@henryseg]

There's a secret trick that I might go into in a future video: With a carefully chosen projective transformation matrix, you can convert an object that looks a certain way in an orthographic projection, into an object that looks the same but this time viewed in a perspective projection. Designing this model to work when viewed in an orthographic projection isn't so hard - it's more-or-less four long cuboids meeting at right angles. Then I applied the projective transformation matrix to make it work from the perspective projection my camera would see.

[@amonynous9041]

fantastic

[@raulgalets]

yeah thats the best one

[@robswatosh1934]

In cabinetmaking I use this 3d trick to show my work. How? Make three paper "7", all the same size & shape. Lay'em out and you'll see how it all works together. With paper. This is from 1977 when I was in school. Still Kool. Rob63...

[@RockAristote]

Nice

[@damianomotta1809]

Hi, i have a question, how u make those projects (not what program, like how you actually male them) it don't look like 3d printing, is it resin printing?

[@henryseg]

It is selective laser sintering - I used the online service Shapeways for these prints.

[@damianomotta1809]

@@henryseg super cool! Thank you for the answer

[@Sakanakao]

Very good. :) Δ

[@andrewvirtue5048]

And to think it is made with only two sides. Nothing more, nothing less.

[@adamvolkinshtein1184]

Gershon Elber work :)

[@eVilLens]

Wow! 🔺

[@OopsOMG]

My brain can't handle this

[@sarahtoussaint6506]

So clever

[@unvergebeneid]

Even with the incorrect lighting, my brain notices that something is obviously wrong but all it can do is throw a "does not compute" exception.

[@melissasabie722]

So interesting to see the visual breakdown of this optical illusion! I found your page after I read an article about your continental drift puzzle and I am not disappointed! 😊 Amazing work!

[@user-zh4vo1kw1z]

Does this work live? Cuz otherwise it feels like it's an overly complicated version of just drawing it on a piece of paper: you are still relying on the 2dimensional representation for it to seem effective.

[@henryseg]

It’s not bad in person, although you do need to use only one eye to look and the position has to be pretty precise. It’s a fair point about 2D being necessary.

[@user-zh4vo1kw1z]

@@henryseg the end did get me thinking: have you tried it on unsuspecting people? Cuz I knew the trick, but for a moment my mind refused to accept the visual of you reaching through the bottom section.... Considering how much our expectations influence our perception, perhaps it would take their mind a bit to work it out. I remember a video from elementary school (late 80's, early 90's), where they showed a similar trick, using a comparable trick. This was later on TV as well, and I distinctly remember the presenter stating it melted his brain a bit at first...

[@Rupninjatrash]

Everywhere i go I see Van der Graaf Generator...

[@Mick_92]

This is the weirdest MA release I've ever listened to.

[@jimday666]

Mind blow

[@kilroy987]

Wouldn't be too impressive on your collectible stand, though. You'd have to look at it through a pinhole.

[@steffdia7080]

Those are already in greek/roman mosaic. There are so many.

[@angst_]

You should make a 60 second cut for yt shorts or insta/tiktok etc. Maybe one with the setup and post second video follow up with how it's done.

[@henryseg]

Already up on Instagram!

[@biostemm]

If you're willing to play with the lighting to get the desired effect, why not just use false coloration to do the same?

[@henryseg]

It wouldn't be so easy (for me at least) to do it with false coloration! I guess it also wouldn't react well to changes in lighting as my hand moves around it.

[@lawgx9819]

Looks possible to me

[@seamusquain2706]

1:38 how can one remake this? i need to try and make it IRL!

[@THEimposterFOSTER]

What is this, modern day brusspup?

[@chiko14june]

I knew this impossible triangle from a book about MC.Escher.....

[@xXdsideXx]

All i see are 3 backward 7's around a black triangle and i can't unsee it now...

[@Gxhbro]

I like to call this the SmadAV triangle

[@devilinsidezozowwg1wga..702]

Easy to make..all 45s

[@XO43137]

Fck that's so intelligent. :)

[@BimBims]

Anjay, smadav

[@sipntea]

what did you learn in math class today?

[@finlayl2505]

Should have named the video "Possible Triangles"; It doesn't sound better on its own, but in conjunction with the thumbnail, I think the contrast makes the video more attractive.

[@willemvandebeek]

I think it should be called Escher triangle, because impossible 3D objects were kind of his thing.

[@jkoblivion4175]

Uau!

[@williamwhitney5266]

Heart Beat _/\_💓

[@Foxxorz]

Reminds me of the rooms where people appear to grow taller or shorter depending on which side they walk down.

[@MichaelDarrow-tr1mn]

it's called an ames room

[@Taotaoba]

How come I don't feel it's impossible 🤣

[@hederahelix622]

I think you could make it for real if you curved space

[@henryseg]

Nil geometry works: kzbin.info/www/bejne/j56pdZdqbrymqLs

[@eh.7759]

It’s just two L’s connected together

[@alcyonecrucis]

“Hi Segerman •

[@indahf.freztiyana824]

Smad-AV...!

[@jimjimgl3]

hands up if you replayed @3:08 over and over...

[@DemonixTB]

check out the ending of antichamber. it has a much better penrose triangle then either of these

[@salvatoremaximus6754]

Smadap foreva........

[@hendrico1502]

thats smadav logo

[@Minecraftgnom]

I was hopeing for a different solution. This has been the exact same trick used for almost all "impossible shapes"... D:

[@henryseg]

I tried! Couldn’t find anything else that worked.

[@Minecraftgnom]

@@henryseg Damn. That's a pity. As I said, it is the most commonly shown solution to all these illusions, so I'm really hoping that there will be some extraordinarily genious solution one day to be added.

[@rianantony]

Thought this was gonna be a Sci fi horror about real life impossible structures and them interacting with the character making the video and flipping him simetricaly and such. Still love it as a normal vid though

[@Marcop_Creative]

I've made this impossible triangle out of wood

[@hai-_-bro]

Clicbate😄 yeah you lvl80 🤣Master

[@kaneko15th]

Smadav

[@lyerillydoh8561]

Wow that was a lot longer than it needed to be

[@Dunning-Krugereffect]

Admitted to cheating. Reported. :)

[@defeatSpace]

I'm a scientific man and 0:10 still got a high-pitch "what the fuck" out of me.

[@frankbraker]

for cyclopes

[@internetpejelajahid2991]

smadav

[@JakubSK]

Sorcery

[@ericheydemann9556]

The Human mind is so flawed