Touch screen devices are becoming an increasingly important part of the gaming landscape. But since they don’t feature conventional game controls, what are the best practices when it comes to adapting traditional joypad-type games to these new machines? Here’s my take on what can make a touch screen game fun to play… and where things can go completely wrong.
Over the last 40 years, video games have taken enormous evolutionary steps, driven by unprecedented advancements in computing power and technology. But something that has evolved at a far slower pace is the hardware used to control them. Paddles, joysticks and joypads all appeared alongside the very earliest gaming systems, and while they’ve been refined and improved over the years, their fundamental functionality has remained largely unchanged.
The mouse (and associated keyboard) ushered in some new control concepts during the 80’s and 90’s, but even then, the vast majority of games that use a keyboard and mouse can be very easily adapted to work with a modern joypad (barring the occasional challenge of games that use the keyboard as a multi-button bank). And while new kinds of controllers have appeared throughout gaming history, such as the U-Force and Power Glove, and a variety of light guns, steering wheels and music game peripherals, they’ve all essentially remained niche products at best, and the joypad has continued to reign supreme.
Even the newest revolutionary control hardware such as Nintendo Wii and Microsoft Kinect are not really changing the way games are fundamentally controlled. Sure, enterprising and creative designers have taken advantage of these new controllers and made some great games that go beyond the realm of the joypad, but the reality is that traditional game control systems continue to dominate gaming, as they have done for the last four decades - because they are absolutely engrained into the way we think about and design games.
Now there are even newer devices that could literally change the way we play games due to the ironic fact that they don’t actually have a controller – touch screen tablets and phones. As more and more consumers buy them and the demand for games on them continues to grow, we’ll be seeing touch screen games becoming an increasingly permanent and prevalent part of the gaming landscape. But will they be a literal game changer? Probably not. Despite enabling new kinds of games and control systems, I think a huge amount of touch screen games will continue to be built around traditional control paradigms. And while some of them will probably work very well, I get the feeling from what I’ve already played over the last year or two, many of them won’t.
Why not? Because rather than being forced to design a game around a standard controller like every console released in the last several decades, designers actually have a blank slate. And it’s that blank slate that is separating the creative clever people from those who simply don’t have the chops or imagination to make the leap from the physical control paradigm to touch.
So bearing that in mind, I’ve come up with what I hope are a few useful golden rules, hints and tips for designers making games that use traditional control paradigms on touch screen devices:
1. Generally speaking, virtual controllers suck
First things first, let’s look at Midway Arcade, a definitive example of how traditional game controls can be incredibly poorly implemented on a touch screen. A recent release on iPad that emulates authentic versions of classic Williams and Midway arcade games, it’s ruined by the thing that makes many, many other touch screen games frustrating and difficult to play: a virtual controller. Basically, the designers of Midway Arcade have tried to recreate an on-screen virtual joypad and buttons to emulate the original controls of the arcade machine. But it just doesn’t work.
For starters, virtual controls are just not ergonomic. They’re difficult and fiddly to use because you have to place your fingers in the right place to get the right movement - something that is very hard to do when the action is fast and furious. A virtual controller also sets physical distance - you have to move your fingers a certain distance to activate a change in direction, and when that happens, you are automatically building in a lack of responsiveness. And that’s a terrible thing to have on a touch screen that is capable of super-fast reactivity.
A virtual controller also means the player has to constantly check it to ensure their fingers are still on it, because they can’t feel anything. Even when the controller moves with your fingers, that distance between left and right or up and down creates issues, because you don’t know where your fingers are on the virtual controller without constantly looking at them.
Ultimately, virtual controllers are not a good control scheme, because they lack tactility and feedback: something that is fundamental to their real-life counterparts. My recommendation is to try to avoid using them - best practice is to never use them.
2. Finger creep. It happens
As I’ve already explained, static controls or virtual controllers are often challenging to use. No tactile feel means constant finger creep. Finger creep means users’ fingers “slipping off the controls” because the user can’t feel where they are.
At the very least, your controls should move with users’ fingers. Better still, don’t use real “controls” - create a system that looks at what the user’s fingers are doing and interprets that movement immediately, wherever they are on the screen: finger goes left, game goes left; finger goes right, game goes right, and so on. If the user has to use two hands to control the game, split the screen in half if you’re having an issue with interpretation.
If you need to confine the controls to a specific part of the screen, at the very least create some room for movement, so that the user doesn’t constantly have to adjust - it really doesn’t have to be that huge, just big enough to allow for that dreaded finger creep.
Check out Cave’s arcade shooters like DoDonPachi to see how fast-action arcade games can work really well using this kind of control system. Dariusburst SP is also a very fine example of a shooter whose controls work without you even having to think about them.
3. Don’t program in mechanical travel
Mechanical joysticks have travel. Virtual ones shouldn’t. If the user’s finger is moving right, moving left should result in as close to an immediate response as you can program, and not require some kind of arbitrary “travel” to go past some invisible point before activating the opposite direction.
Best practice here is to enable users to adjust the “responsiveness,” ie, the amount of travel required by the finger before activating movement in the opposite direction.
Gridrunner is a good example here. It’s almost perfect, but does have a little feeling of sluggishness that I’d have like to be able to adjust by tightening the responsiveness. Definitely a good case study though. Infinity Gene is pretty decent too.
4. Adjustability is a player’s friend
If at all possible, controls should always be adjustable, particularly on games whose controls are pseudo-analog, or feature controllable objects that have weight or acceleration curves.
Enable adjustment on linear, convex and concave acceleration curves. This will help users find the right reactivity and “weight” - and it’ll help make your game “feel” perfect.
5. Virtual buttons also suck
Like virtual controllers, virtual buttons are also challenging to use. Mashing a flat glass screen is not fun. If at all possible, use an autofire option, preferably with some kind of adjustment - perhaps a finger held down and slid to dial up or down the firing rate.
If you’re making a game with multiple buttons, let the user lock them a certain distance apart to suit themselves, and at the very least enable them to move and follow the users fingers. Better still just let users tap the screen or an area of the screen to fire without having to hit a small, specific area. As always, no tactility and feedback means it’s easy for users to miss the buttons completely, which makes the game very frustrating.
6. Hands are not transparent
Remember: hands can obscure the screen. Full screen games might look great, but if the user has to put their hands on the screen and important game events are obscured, you’re making the game unplayable. Or at the very least really annoying.
Design around that: perhaps create control areas are where nothing important happens, or simply build in non-critical game areas where non-essential info is displayed that doesn’t matter if it’s covered up.
For games with selection systems, rather than use drop-down menus, try thinking of other ways of cycling through options – perhaps a double-tap, or hold-and-slide.
7. Tilt controls: can be fun. But only with the right games
Generally speaking, tilt is most effective as a gaming controller when paired with games that require slow, deliberate movements. Aaaaaaaaaaaaa is a good example of that.
The problem with wafting a tablet around is that there’s no feedback, meaning users don’t have any idea where the center point is. This creates a very vague feeling of control that as a consequence can feel unresponsive or sluggish. Which is why these controls aren’t much fun when used with faster, more complex games. Hyper Light is a fast-action arcade game that’s potentially incredibly good, but simply serves to showcase poor tilt controls. Midway Arcade also has tilt control options, and they’re even more horrible then the virtual controllers. Definitely check them out to see how it shouldn’t be done. The Incident is one of the few faster action games that I’ve played that does work reasonably well with tilt controls.
The other thing to bear in mind with tilt controls is that they do make your game somewhat embarrassing to play in public. It also makes it surprisingly tiring, so if you’re designing games around tilt, make them short and sweet, or at least “burst” gaming with the ability for players to pause between rounds, or play the game over short periods.
8. Tablets: a chiropractor’s best friend
Tablet ergonomics are quite poor, especially when using heavier devices, and people hold them in many different ways. That’s an important thing to bear in mind when making a game. For example, if your game requires lots of finger work, it might actually be hard to play while holding the tablet. If that’s the case, ensure it’s easier and more comfortable to play if it’s resting on someone’s lap or table. Test it out and tweak if necessary. It’s surprising how many games can cause aches and pains quite quickly because they are not particularly comfortable to play.
9. At the end of the day, don’t be afraid to try something new
Touch screen gaming is still a relatively new thing, and I believe there are many new things yet to be discovered, both in terms of new game concepts - and new controls.
Be experimental. Try new things! Tap to aim. Tap to move. Follow-a-finger directional controls. Dynamic sequence aiming and/or movement (tap multiple targets and then fire for example). Multi-touch controls with finger slide to dynamically adjust parameters like shooting, jumping rate, acceleration curves. Two or three fingers held to the touch screen and then rotated simultaneously to turn or manipulate objects. Develop intelligent controls that recognize the amount of fingers on the touch surface, or the distance between two digits.
Ultimately, think creatively. Be daring. You never know, the creative ideas you’re thinking about could very well be the next big thing, ushering in a whole new kind of game - or spin on an existing game genre - that touch controls take to a whole new level. Just always remember, though: it’s all about the playability. Doesn’t matter how good your game looks or sounds - if the controls render it unplayable, it’s a failure.
Some of my favorite touch games that feel great are Osmos, Flick Soccer, Triple Town, Dungeon Raid, Galcon and Draw Something. All are simple games, but make great use of the touch screen to deliver a natural, intuitive experience. I’d definitely recommend trying them out if you want to experience good controls in action - as well as play some entertaining games in their own right.