31 portals of impossible shape 

Ordinary portals are flat, but it's not an axiom. And I tell you about such shapes of portals, which are difficult to guess, not to mention to imagine. In particular, here is a portal in the form of: a cylinder, a Mobius strip, a trefoil knot and much more. Some of the portals shown were opened by myself, and some by other people.
Chapters:
00:00 Cylindrical Portal
02:08 Introduction
02:45 Surface portal
04:16 Linear Transformations
05:10 Möbius strip
10:01 Monoportal
12:17 Möbius Monoportal
13:35 Triple portal
17:34 N-monoportal
18:30 Shifting monoportal
19:11 Scaling monoportal
21:02 Tilings
23:09 Chain
23:36 Knot
32:29 Other
34:16 Other projects
35:08 Conclusion
References:
[1]: optozorax.github.io/portal/ - my demo
[2]: / 1080438078852947969 - avatar
[3]: • Что будет если помести...
[4]: sirxemic.github.io/wormhole/ - online wormhole simulation
[5]: optozorax.github.io/portal/?s... - nonlinear motion scene
[6]: raytracing.github.io/books/Ra... - book about raytracing
[7]: kenbrakke.com/polycut/polycut... - PolyCut
[8]: • ТЫ БЫ НИКОГДА ТАКОЕ НЕ...
[9]: • How Does a Non-Reversi...
[10]: • Portal Reloaded - Game...
[11]: / @onigiriscience
[12]: • Blocky Knot Portal v2
[13]: • Self-Hiding Knot Portal
[14]: • Thurston, Knots to Narnia
[15]: www.imaginary.org/program/kno...
[16]: • The Insane Math Of Kno...
[17]: contest.zenmagnets.com/56-5-c... - Cubic Eight Knot
[18]: paulbourke.net/geometry/borrom... - Borromeo Rings
[19]: • Non-Euclidean recursiv...
[20]: • Portals to Non-Euclide...
[21]: unasanu.xyz/
[22]: t.me/optozorax_dev - my telegram channel
[23]: • Portal Teaser Trailer
[24]: • Portal 2 Physics - Por...
Places where I write:
Telegram - t.me/optozorax_dev

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