With Microsoft Kinect and Nintendo 3DS dominating the E3 headlines, it is perhaps too easy to overlook the strong showing of PlayStation Move at the industry's showpiece event.
The launch line-up of games is looking impressive: bespoke Move titles like Start the Party are genuinely great fun, previous hits like Heavy Rain are getting the upgrade treatment with well-realised interface implementations, while forthcoming heavy-hitters from Sony such as Killzone 3, Gran Turismo 5 and LittleBigPlanet 2 are all slated to support the new hardware.
While Move doesn't have the sci-fi allure of Kinect, the foundations of its basic design are extremely strong, and its performance in terms of precision and latency is best-in-class. There's also the device's basic flexibility: Move can "do" gesture-based games similar to Harmonix's excellent Kinect title, Dance Central. The E3 unveiling of the accomplished SingStar Dance proved that while full-body scanning can't be achieved, the overall effect turns out to be much the same.
Moreover, unlike Kinect, core titles can be easily supported. SOCOM 4 demonstrated that Move adds genuine value to a tactical shooter in a way that simply couldn't be implemented on the competing HD motion controller, providing a naturally intuitive interface that we found to be markedly superior to the standard DualShock setup.
However, it's fair to say that reception to PlayStation Move hasn't been uniformly positive. There's a train of thought that suggests perhaps Move doesn't offer enough to differentiate it from the Wii remote, that the accuracy and performance it represents isn't the hook required to bring the casual audience to the PlayStation 3.
So, when Sony offered us the chance to speak one-to-one with R&D Manager of Special Projects, Dr Richard Marks, that was the very first point we put to him...
Digital Foundry: At the Sony media conference, the emphasis with Move was on fidelity and precision. From a design perspective, that's the Holy Grail: ultra-low latency and accuracy. But does that tally with the needs of the audience that Sony needs to attract to the PS3? Would a casual gamer really be attracted to Move because of its precision?
Richard Marks: My colleague Anton [Mikhailov] has a really good way of summarising that actually. The thing that matters to the average person is not how precise it is or how responsive it is at all. Those words don't have much meaning to them, but how well connected you feel to the game matters. They want to feel like their actions matter. They don't care if it's sub-millimetre or anything like that. They want to know that what they're doing is having an effect. That 1:1 feeling of it doing the right thing is all that matters.
The broad numbers aren't so important but the fact that it feels right when you use it, that's what matters. The way we think about it is that there's a data layer and that has to be really good. On top of that you have the interpretation layer: how you choose to interpret that data. We want to give the game developers as much freedom as possible to interpret the game data so if the data is as good as possible they have more freedom to interpret it as they want. They can smooth the heck out of it, make it super-sluggish or super-stable or they can make it super-responsive. We want that creative freedom to be available to the game developer.
If we wanted them to make one kind of game, we would have tuned everything to that one kind of experience. That's all it would do, and that's not what we tried to do.
Digital Foundry: When you began your research, did you look into the z-cams, like Project Natal?
Richard Marks: Yeah, actually we did...
Digital Foundry: You - personally - were doing the precursor work to that before with EyeToy, right?
Richard Marks: Right. I'm still a heavy proponent of 3D cameras. I think they're really interesting technology. We had many different 3D camera prototypes and we had our game teams look into that to evaluate what they could do with it. There are some experiences that it can do that are really neat but there just weren't enough experiences that made it make enough sense as a platform-level controller.
Coming back is that sometimes we need buttons to have certain kinds of experiences. Other times we need more precision than we can get out of those cameras. We need to know exactly what you're doing with your hands, especially in the more hardcore experiences.
Digital Foundry: So you're saying that the technology actually limits the kinds of games you can make?
Richard Marks: If it's just that 3D camera, yeah I guess. That's what we ran into with EyeToy. When you have only the camera, it's a magical feeling but sometimes you just wish you could select something. I don't want to wave to click a button.
Digital Foundry: Weirdly, they seem to have Microsoft Kinect adverts in the E3 toilets, saying that this is the controller that's taken five million years to develop. That five million years doesn't seem to encompass the evolution of the hands or the fingers. Kinect is cool but it can't scan fingers. That's where the lowest possible latency is, the most direct connection you have with the game.
Richard Marks: In one of his books, Isaac Asimov talks about the difference between humans and animals and he believes it's our hands that make us different, more than our brains. Most people say it's the brain that's so much better, but he says it's the hands. He says that the ultimate interface to a computer isn't a probe that jacks into your head, it's where you insert your hands into this device. You have so much bandwidth going through your fingers. It's science fiction but...
Digital Foundry: A lot of science fiction becomes science fact.
Richard Marks: There's another big factor. Like you said, you have so much fidelity with your fingers and wrists. It's such a high dynamic input. We do want to give that to people, but also the tactile feedback of knowing you're making a click is such an important thing. When you make these gross movements [gestures] you know that you're doing them. When you're doing subtle things it's difficult to know that the system "knew" what you meant, or accepted your input.
So the click of a button is equally the input, but also the feeling that it actually occurred. That's such an important thing. If you make a gesture to make something happen all the time, you don't have that immediate feeling of knowing that it worked. You have to wait and see if it happened and that just slows everything down. A click gives instant knowledge...
Digital Foundry: There's something annoying about gesture control: the response mechanism. There's 1:1 tracking and that's just brilliant but then there's also gesture recognition. At some point the CPU has to decide that the motion you're performing is a gesture that should be acted upon, and only at that point will it begin the effect, the animation on-screen or whatever.
Richard Marks: I'm not a big fan of gestures myself. There is a place for them in certain types of game but I think the worst thing is that you need to do all this kind of "stuff" and it's the equivalent of one button press. You've replaced that one button with all of that?
I don't want to just be harsh about gestures. My favourite use of them would be something like this: imagine you're casting a spell by drawing in the air and how well you draw it matters to the spell strength. Then it actually starts to have a meaning. I'm not just trying to do a button press. How well my form was is scored...
Digital Foundry: You have gesture control in Move of course...
Richard Marks: Yes, we can do that.
Digital Foundry: Let's talk for a moment about the Navigation Controller. Is that effectively a redesigned, pared-down DualShock? Does it add any kind of additional motion control to the system?
Richard Marks: No, it is exactly the left "hand" of the DualShock. And it's not necessary. You can always use the DualShock instead of the sub-controller.
Digital Foundry: But that would be a bit of a handful on a game like SOCOM...
Richard Marks: I found that if you're sitting down and it's on your knee, it's not a problem at all, it feels pretty natural. But if you want to stand up and you want a user-friendly game then you use the sub-controller.
Digital Foundry: It seems to be the case with Kinect that it operates on a principle that the more features you use, the more CPU time is consumed. So there's a base-line, a fixed cost, but then there's a bit extra if you want to use the RGB camera, or if you want to use voice control. Is everything integrated in Move? For example, surely for the tracking you're using the camera all the time? Is it a fixed cost?
Richard Marks: It's very nearly a fixed cost. There are two tiers of cost, really. There's two controllers and four controllers. The extra cost is negligible, there's no extra memory required. On the CPU, one of the SPUs does a little more work to track the other controllers.
Digital Foundry: The head-tracking we're seeing in some of the games is intriguing. How does it work? Can it only track the physical movement of the head, or can it pick up actual changes to the direction you're facing?
Richard Marks: The head-tracking is not part of Move, it's part of PlayStation Eye libraries we provide. There are many ways and flavours we can use it. We have detection, where it just finds a face. We have things like smile detection, things like that. We also have tracking and lots of different flavours of tracking. The London studio created their own, for example, they have a lot of experience with EyeToy. Everyone always thinks that head-tracking would be the ultimate thing but when you're playing a game you rarely look away from the TV.
Digital Foundry: You'd need to constantly changing the direction of your face, sure. You'd need to be consciously doing that as part of the control scheme.
Richard Marks: We found that although at first you might think looking left and right is more natural, actually leaning left and leaning right works better. If you hook up head-tracking to a first-person shooter, you can lean around a corner. You can peek out and peek in. We've been looking into that for games where there's cover you can hide behind. It's a really neat feeling.