Q: Could you go through the process of how you designed move. Were you looking specifically at devices like the Wii?

Richard Marks: PlayStation Move is the direct result of the work we did with EyeToy, so we really did start with the camera portion. Back in the year 2000 one of the tech demos we were doing, even back then, involved a coloured ball on a stick and we were trying to track that around. So we were trying to do the same sort of thing with EyeToy, but we couldn't do it reliably or accurately enough to be a good gaming interface.

We did as much as we could with just a camera: that was my focus. But we kept running into problems, you couldn't do all the experiences we wanted to do and also around that time DualShock was coming out for PlayStation 3, it had built-in censors and gyros that gave different kinds of information about rotation, whereas the camera could give a lot of position information.

So combining the two made a lot of sense. And also the big other factor that we were realising at the time was that it feels good to have something in your hand for a lot of games. It's not just that it gives you more input capability, which it does. But also it just feels right. Like if you have a tennis racket it feels better to have a controller in your hand. If you have a magic wand, a sword, a gun, it all feels better.

Q: So you weren't interested in trying to shed the remote all together like Kinect inevitably did?

RM: We were very interested in it in 2004. But then we just decided it wasn't a viable product in our minds. EyeToy can already do a lot of that already. We hit a lot of the same limits with the 3D camera that we had hit with EyeToy so it didn't seem like it added enough value.

I had demonstrations with the 3D camera where you're just casting spells or drawing. Doing it with your fingers is kind of neat but in the end it feels awkward. I would often just pick up a stick and it felt better.

Also around that time was when the Wii was coming out. The goal with EyeToy was to have a new way to play games and have something that people who wouldn't normally play would play. The Wii had also accomplished that a little bit with a very simple controller. So we realised we didn't have to get rid of the controller as long as we didn't make it too complicated. [The controller] was easy to use, you could get all the benefits of having buttons. But we could also have all the benefits of tracking the controller with a camera, and that's when we basically started the productisation of Move. We pay attention to what's going on [in the market], to the Wii in particular. We tracked how successful that was. With Kinect, we had already made our decisions of what to do design-wise before Kinect. We had already been working with the 3D camera before that.

Q: Design-wise how much inspiration did you get looking at the Wii.

RM: Our design metaphor is very different. The Wii is really going for a remote control metaphor. focused more like a handle. Like the handle of a baseball bat, or a tennis racket, or a sword, or even a gun maybe. So it really feels like something you would want to hold in your hand and it feels good in your hand. It's tapered because smaller hands will hold it up higher, closer to the buttons, whereas bigger hands will be further away from the buttons. It also slips less easily because it's tapered, that's a well known handle design thing, like axes and things like that do. Maybe it would be impossible to make a one handed device that people wouldn't compare to Wii. But I don't think it looks very much like it. Maybe the thing is we have one big action button, I mean we already have the PlayStation buttons part of our design so. The navigation controller does have a very different set up of buttons than on the nunchuck. There's no d-pad on a nun chuck. It's not inspired by the Wii but of course the Wii already existed when this was designed.

Q: What is the function of the sphere?

RM: The camera sees the sphere and that's how it knows where the controller is. If I don't have that then it doesn't know where you are. This is what you have with Wii: It doesn't know where [the controller] is. The big difference between this and Wii MotionPlus is how the camera sees the sphere for positioning.

[Mark is holding a Move controller. His image is projected on the television, and the controller is interpreted as a sword. He lifts his arm up, and wiggles his wrist. The sword reacts precisely.]

The angle of it controls the position of it too. If you point [the controller] up then the sword lifts off. But you couldn't lift the sword up and point it down; you couldn't do that in Wii MotionPlus.

[He lifts the sword up so it points at the ceiling then, arm above head, he turns his wrist so the sword points to the ground.]

You couldn't reach into a scene and touch objects. Because we have the positioning you can really enter into a 3D space.

[He brings onto the screen a floppy-looking marionette.]

You have a virtual marionette character, and you can interact with him. You can reach in, pick up his arm, and reach down to his leg and pull backward. His leg is balancing on my sword right now. You can't interact with a 3D world if you don't have that positioning. You can squeeze and pick the character up in the air, turn him upside down, throw him.

[He loads an animation of a flame.]

Another gameplay thing we really like is this very free-form fire ball in your hand, you can have fire emit out of your hand, and control where your hands are. I can make a big wide area of fire, or I can make a very narrow focus. I can throw it in any direction. It's very visceral and it feels directly mapped to where my hands are. I can also squeeze the analogue key button to control the fingers and it has the feeling of grabbing stuff. Switch to first-person view and you can grab or fight.

Q: Both Kinect and Wii seem heavily slanted toward a social, casual demographic. Are you going to be focusing on casual gamers or do you think that this kind of device will be able to cater to a hardcore market?

RM: The focus is across the whole spectrum of PlayStation owners so it adds a very good casual control to our system but also because it has so much fidelity and precision it can do a lot of core experiences as well. It's really intended not to just be for one audience.

Q: So would this have an application beyond gaming even?

RM: Yeah I was talking to some surgeons. They were talking about laparoscopic surgery simulators. They were saying this feels very much like their $100,000 simulators do for surgeons and they'd much rather do something at a lower cost.

[Marks then switches to a model of a head]

Even for creating user generated content. You can start with something like a head, you can reach in to a head, grab it, squeeze [the control] tighter and make [the chin] more pointy. Extend the nose out, grab the ears, you can create monsters very easily this way. Move is very good for user generated content because it's very literal. Just grab things. I can switch to a carving tool, I can carve something like a scar across his head. Switch to a painting tool and you can paint.

[He switches again, this time it's branches on a tree in an open 3D space]

The goal of this demonstration is to show that there are a lot of ways to use move and it's not exactly like the Wii, a lot of people are confused with that. This is a chameleon FPS. I am a chameleon, these are my hands. I can reach into the world, grab a tree-branch. This is a very different way to use the Move but it's a way to explore 3D space in a way we never have before. Chameleons actually control each eye independently so I can switch to that view where each eye is under my control.

[The image gets divided. Marks holds two Move controllers, with each controlling the camera for either eye on the chameleon.]

Q: Do you think that 10 or 15 years from now this kind of motion-based device will be a standard aspect of gaming?

RM: I think that in the future we will always have a kind of controller that has spatial data like this does. But I don't think it replaces DualShock at all. DualShock is a really good abstract device, there's lots of buttons and analogue sticks you can map to anything abstract. People really understand it and like it. I don't think you'll see this get replaced, but I also think this will always be a part of the system. It will modify in some ways maybe but it will always need to be putting this sort of information in.