[After his Innovation Award win at the IGF this year, our own Eric Caoili talked to feted indie designer Jason Rohrer about Between, inspiration and thinking different.]

Explaining Between to someone in words is fairly challenging -- and when you try, you feel you get a glimpse of creator Jason Rohrer's intention.

The prolific designer's already gained a rep for thought-provoking, layered work with free to download titles like Gravitation and Passage, and with Between, he takes his most substantial step yet into the arena of two-player games.

For details on his process and concept, we spoke directly to Rohrer about Between, winner of the Innovation (Nuovo) Award at the 2009 IGF:

What kind of background do you have making games?

I've been programming actively for twelve years, but only making games for three. At first, I just made a game or two here and there, dovetailed with my other programming projects (peer-to-peer systems), but over the past year and a half, following the minor success of Passage, I've been doing nothing but game development, and I released nine games in 2008. I just finished my 13th game, Primrose, recently.

What sort of development tools did you use?

I've used GameMaker for some prototyping and 1-week sketch projects, but all the rest of my games are programmed from scratch in C++. I use open-source development tools, with GNU/Linux as my main working platform. I edit in Emacs and compile using GCC, using Makefiles invoked from the terminal.

I've fallen in love with the open-source mtPaint pixel editing program, but I end up using The GIMP for a few graphical tasks, too. All the sounds in my games are procedurally generated directly in the code, so I don't use any audio editing tools. My cross-platform video and sound library of choice these days is SDL, combined with OpenGL as needed.

The upshot is that my games compile and run on almost every standard platform, and porting them to more finicky platforms is not very difficult.

What spurred you to create a two-player title with this theme of isolation?

After making a slew of single-player games, I started reflecting on the history of our medium. In fact, the vast majority of games were multi-player affairs before this strange little box called the computer came on the scene.

Are we missing something? Has our obsession with single-player blinded us a bit? Go was constantly brought up in conversation as one of the greatest, most beautiful works in our medium, despite the fact that it is a folk game with no "designer" behind it.

I found that if you wanted to make a single-player game with the depth and beauty of Go, you simply could not---at least not without relying on randomness as a crutch.

The beauty of deep two-player games comes from the back-and-forth question and counter-question of "here's my move, now how are you going to respond?" I've heard it described as two players making an endless series of puzzles for each other to solve.

Randomness accomplishes something similar in a game like Tetris, but it's just not as deep or satisfying, because it it doesn't respond at all to the choices that you make.

So I had it in my head for a while that I would never make another single-player game again. Crude Oil was my first two-player game, a 1-week game sketch about leasing and pumping oil reserves in a changing market. I knew that my next game had to be two-player as well.

As far as the subject matter goes, I really wanted to tackle something bigger and more ambitious than the themes that I had dealt with in my previous games. All of my other games could be distilled down into words pretty easily, and in some cases, they were (in my Creator's Statements), so why did I need to make them in the first place? Why not just communicate with words?

I was really impressed with what Jonathan Blow had done with Braid, and also with what he said about it publicly, that he simply could not put his intentions into words. After I played the game extensively and thought about it a lot, I realized that I had come to understand it pretty deeply, but that I couldn't really put my understanding into words either.

Braid is about something really big and complex, about humankind's relationship with this particular thing. Jon couldn't get his arms all the way around it. He couldn't corner and collar this beast, but he could point at it and hope that you could see at least part of it over there.

And that seems like a great utility of art: to express the complex and subtle things that we have trouble expressing in any other way.

So I wanted to make a game with that kind of ambition. I felt around in my life and mind, and I found this thing that had always intrigued me, this manifold of concepts that seemed to touch a lot of important human endeavors. I wanted to make a game about *that*. I sum it up in words as "a game about consciousness and isolation," but that's just a road sign pointing you in the right direction.

Since this "thing" that Between is about concerns our relations with other people (or illusions of other people, you never can tell), it was very natural to make a two-player game about that.

I didn't set out to turn multiplayer conventions on their head or anything like that. I set out to make a game that expressed what I wanted to express. Seeing the actions of the other player only indirectly was an important part of that.

Have there been any other multiplayer or single-player experiences that you've seen in other titles that you've admired with the same theme, or possibly with a similar approach?

Not that I'm aware of. Between was not directly inspired by any particular game. The inspirations came from the realm of philosophy instead, from the work of folks like Hume, Descartes, Quine, and Lewis, and of course from my own thinking along these lines.

Which came first -- the tower puzzle, or the sleeping/waking concept? Which was built around the other?

Sleeping and waking was an important part of my thinking from very early in the design process. We have the following problem: we like to believe that the people we interact with on a day-to-day basis are conscious entities just like we are, but then at night, we dream about people who behave like conscious entities too, and we can't seem to tell the difference until we wake up.

So, from early on, I was exploring this idea of differentiating the truly conscious from the non-conscious, distinguishing the waking state from the dreaming state.

Some of that ended up in the final game, but other parts did not. For example, there are no unconscious entities operating in the game---all artifacts are either produced by you or by your partner.

So I had this idea of waking and dreaming and trying to separate the two, and maybe the waking state would be the thing that joins the two people together. It took me a while to figure out exactly what the two people would be doing on these various planes. Trying to find each other? Trying to accomplish some task together? Trying to communicate something complicated to each other that ends up lost in translation?

At that point in my design notebook, I have the following real-life example: "I know what Braid is about, but I cannot communicate it to you." I wanted to capture something like that---how hard it can be to communicate something abstract to others that seems obvious to us.

The towers became a suitable metaphor for communication. You build it, and the other player might see it, but they might not understand it or read it the same way that you do.

Between ended up being a self-reflexive work in a way, because it's about this thing that I have trouble communicating. I build it (the game) and show it to you and say, "See what I mean?" You play it and scratch your head, and it might not make sense to you at all. But the game seems so clear to me, so symmetric and ordered. To you it might just be a jumbled, confusing mess.

Some people have pointed out that the tower construction becomes tedious after a few rows. That's also part of the point, because when you're driven to communicate something complex to another person, you often need to go to great, tedious lengths (like, several months of game development) to carry out that communication, and it still might not be fully understood by others.

What lessons were you able to take from your previous projects -- Gravitation, Passage, etc. -- and apply with Between?

The basics of game implementation have become easier and easier for me as I make more and more games. For example, I've been able to use the same music-generation code, with slight modifications, for all three of these games.

On the other hand, I decided to use full-blown OpenGL code for Between instead of manually rendering pixels to a frame buffer (which is what I did in Passage and Gravitation). There were simply too many complicated effects needed, like the block constructions morphing, and it seemed like it would take me forever to write pixel-manipulation code to do all that, plus it would end up being too slow without graphics acceleration.

But once you're in OpenGL, the tendency is to use smooth object motion and ignore pixel boundaries. Between still has a pixelated look, and I wanted it to be "real" about that. I took a lot of the things that I learned about screen blow-up factors and such from frame-buffer graphics and applied them in an OpenGL context.

The game is really complex in what players can do, and in what's available for players to accomplish; how would you succinctly describe the game and its goals to others who aren't familiar with the concept of art games?

Between is a game where you must interact with and communicate with another person through seemingly impenetrable barriers. The challenge comes not from what you need to do---build a tower of 27 blocks---but from figuring out how to do it with the limited resources at your disposal and how to communicate your need for help to the other person who is playing with you.

Between is a game that actually becomes *harder* if you take a peek at your friend's screen or chat with your friend as you play. That sounds impossible, but it is true.

Were there any elements that you experimented with that didn't work with your vision?

No, I fleshed out every major detail of the design in my notebook before I started implementing anything. The final game deviated very little from my notes.

Is the two-player setup and the method of connecting players -- "friend codes" and waiting at an undecorated screen for a stranger to play with -- what you envisioned from the beginning? Did you explore any other possible setups/methods.

From my experience with Crude Oil, which didn't use a centralized server, I knew that a centralized server was necessary to avoid firewall and router woes. But how do you quickly and easily connect to your friend once you both connect to the server? The use of codes seemed like the most elegant approach, instead of picking your friend from a lists of connected people or whatever.

You want to connect to your friend and to no one else. The use of a code ensures that this will happen. There isn't any other way to do it, at least not that I can think of.

Players can wait a long time waiting for another stranger to play with -- was this by design?

Connecting with a stranger is meant to be a fall-back mode for people who really cannot find a friend to play with. You never know when another person who is looking for a stranger might show up to pair with you, so you might need to wait for a while. But generally, you can't trust a stranger anyway---how long will she play before dropping out of the game and leaving you hanging?

It seemed like a less-than-ideal game experience all around: something that I had to support, but not something that I wanted to encourage. Hopefully, most people get bored waiting for a stranger and then try harder to recruit a friend.

But the long wait was certainly not intentional. Again, there's no way around it: you simply need to wait for another person who is also looking for a stranger-to-stranger pairing. That's reality, not a design issue. The wait is really a factor of how many people are trying to play the game at any given moment.

If you could start the project over again, what would you do differently?

Sorry if this sounds like a cop-out, but this project went pretty much as-planned. This was my 12th game, so there weren't any big surprises.

How did Esquire.com come to host the game?

They were doing a story about me for their "Best and Brightest" issue, and as part of that, they often ask the creative-types on the list to do a piece of work for the issue. For example, they had their B+B playwright write a series of mini-screenplays that their B+B actor fleshed out in a series of pictures. They wanted me to make a game for them, or at least give them a new game to distribute.

There was even some talk about an "Esquire Game," but that never panned out (what would it be about, Eskie chasing cheesecake?). I was in the process of making Between to submit to the IGF, and it just seemed like a natural fit.

You just released Primrose to iPhone, and before that, a port for your PC game Passage. Do you have any plans to release Between or any of your other previous titles to the iPhone platform?

Porting Passage to the iPhone seemed like a natural way to test those waters. It already had a bit of a following, and it only took me a week to get it working---a great crash course in iPhone development. Primrose was designed specifically for the iPhone (but it also runs on other platforms, too).

I don't have any specific plans about porting other games. Between would be a good fit in terms of technology, because of the always-on internet connection, but a terrible fit in terms of the iPhone's casual audience.

The other problem, generally, is that games which weren't designed for a touch screen generally don't work well on a touch screen. Passage is a perfect example, where my custom touch "widget" really isn't as comfortable as four arrow keys on a keyboard. Gravitation's controls are really twitch-sensitive, so I fear that it just wouldn't work. Between uses nine keys on the keyboard. How would I make something like that work on the iPhone?

What do you think of the state of independent game development, and are there any other independent games out that you currently admire?

The past year or so has seen the body of interesting, thought-provoking games grow dramatically. Unfortunately, I don't have time to keep up with new work as much as I would like to.

I've already mentioned Braid---that is by far the greatest work in the medium of video games, in my opinion. I've recently taken a strong liking to work of Daniel Benmergui. Also, I just played a few of the recent games by Terry Cavanagh, and I thought they were excellent.