Examining Portal's Teleportation Code

Gamasutra is running a story deconstructing the mechanics of Portal's teleportation programming. They present a snippet of Portal's code and a downloadable demo. They ran another article in this series earlier this year with an analysis Mario Galaxy's unique take on physics. We've discussed the development of Portal in the past. "Teleport mechanics in video games are nothing new. Puzzles from the original Gauntlet were memorable -- and more than likely, that wasn't the first game to use teleportation as a gameplay mechanic. The difference between Portal and all those that came before it is that Portal's teleportation acts as a frictionless tube between point A and point B. Physics are still hard at work inside the frictionless tube. Instead of simply repositioning an object from point A to point B, the player enters point A with full velocity and exits point B with the same speed, but moving in a new direction." Update: 8/26 at 19:37 by SS: Dan notes that the code was not directly from Portal; it was written to approximate Portal's physics.

Frictionless tube?

[Anonymous Coward]

Your mom has a frictionless tube.

First post?

Portal

[CaptainPatent]

Regardless it's a lot better than quantum teleportation. [xkcd.com]

Re:Frictionless tube?

[Chris Burke]

For friction to be present, the object being inserted into the tube must be large enough to touch the sides. That must be your problem.

But...

[i.r.id10t]

But... can they telefrag?

I just love the sound of 2 bodies trying to occupy the same space at the same time in the morning... or afternoon... or evening...

Too verbose

[Anonymous Coward]

>>Physics are still hard at work inside the frictionless tube. Instead of simply repositioning an object from point A to point B, the player enters point A with full velocity and exits point B with the same speed, but moving in a new direction."

Should be "Speedy thing goes in; speedy thing comes out."

Ahoy, GlaDOS!

[Stanistani]

I want to see the nautical version, Porthole.

The code

[anomnomnomymous]

The code is a lie!


Ok, sorry...

Re:Ahoy, GlaDOS!

[Darth_brooks]

I'm waiting on the hot grits version, Portman

Re:M.C.Escher has good OLD examples of the concept

[Anonymous Coward]

Speaking of, whens he gonna put a new album out?

Next step?

[Aranwe Haldaloke]

Porting Portal's portal code?

Re:Frictionless tube?

[jollyreaper]

For friction to be present, the object being inserted into the tube must be large enough to touch the sides. That must be your problem.

THAT'S WHAT SHE SAID! -er, shit. *self pwn*

Re:Ahoy, GlaDOS!

[Underfoot]

I want to see the white water version, Portage.

Re:WTF

[kestasjk]

It didn't answer the main question for me: How does the code which accelerates players downwards work?

It must be using some kind of vector mathematics for mapping acceleration onto velocity, and velocity onto position, but I'll be damned if I can figure out how they expressed that in an algorithm.

Re:It would have been more fun

[Underfoot]

We need a Pratchett based online FPS! Dwarf Bread for weapons; you can play as a Gollum; Discworld based physics.

That would be super-sweet!

Re:Ahoy, GlaDOS!

[Captain Splendid]

I'm waiting on the drunken lawyer version, Port

-Rowley Birkin, QC

Re:Ahoy, GlaDOS!

[Anonymous Coward]

The grits are a lie :(

Re:Next step?

[saboola]

I'm not a portal porter
I'm a portal porter's son
And i'm only porting portal
Till the portal porter comes

Re:Portal

[ElizabethGreene]

First thought: "Hey, if it can work within or near the event horizon of a black hole we could time travel!".

Second thought: "Wound this violate one of the laws of thermodynamics?"

Third thought: "I need a life."

Re:It would have been more fun

[Punko]

Dwarves on Discworld don't fight golems. They fight trolls. This is why the internet needs more dwarves.

Re:It would have been more fun

[xouumalperxe]

multi-hundred pound canon

Omnianism has loads of holy books, but I don't think even those collected amount to several hundred pounds.

Re:Too verbose

[elrous0]

My ex-girlfriend used to use that exact phrase all the time.

Re:M.C.Escher has good OLD examples of the concept

[Chris Burke]

Speaking of, whens he gonna put a new album out?

Are you talking about M.C. Escher who designed the crazy staircase house? Or David Bowie, who lives there?

Re:Ahhh

[MobileTatsu-NJG]

I got a great blow-job last weekend. It was like she was making out with my dick.

It was wonderful.

And when you were done, did you type 'afk' and light a cigarette?

Re:Ahoy, GlaDOS!

[MobileTatsu-NJG]

I'm waiting on the drunken lawyer version, Port

I'm waiting for the Wii version, P.

Re:WTF

[billsnow]

velocity is the correct term. even though the moving object changes direction within the 3 dimensional space, the vector value must be retained in relation to the plane of the original portal and translated to the plane of the new portal. don't feel bad; as an engineer, i'm accustomed to correcting physics majors on such topics.

Re:Portal Physics 101

[Atzanteol]

Sooo... Speedy thing goes in, speedy thing comes out?

Asteroids anyone?

[mfnickster]

Didn't Asteroids have prior art on this..? :)

Re:Ahoy, GlaDOS!

[shadwstalkr]

I'm waiting for the Wii version, P.

I'm waiting for the Scrabble version, Portmanteau.

Re:But...

[Anonymous Coward]

I just love the sound of 2 bodies trying to occupy the same space at the same time in the morning... or afternoon... or evening...

And stop peeking into our windows, you're creeping my wife out.

Re:Portal

[beav007]

It's not the execution, it's the cake.

Note that, in Portal, execution and cake seem to be linked...

Re:Portal

[grahamd0]

It's not the execution, it's the cake.

I didn't want him to think of me as a liar.

Re:Ahhh

[yanyan]

+1, Touche.

Re:Frictionless tube?

[noundi]

Your internet has a series of frictionless tubes. *high fives Ted Stevens*