Interface Design and Unusual Platforms, Part 3

This is the third and final installment of Interface Design and Unusual Platforms. If you haven't read the first two, please start here.

The first two posts were about the incredible variety of hardware available, and how each one provides a unique source of input from the user. In all of my design work I like to start with answering the question "what is unique about this hardware, and what can I do with it that I couldn't do with any other hardware?"

This post will be focused on what I would argue are the two most common pieces of "unusual" hardware - mobile and VR - and how we as designers need to step away from the mindset of designing for mouse and keyboard.

Not long ago I played a VR hangman game where the user would fill in the hangman letters using a digital keyboard floating out in space, and would reach out with their motion-tracked controller to "click" on the keys using the trigger on the controller. There are many VR experiences that attempted to have the player "click" on things in the world, however this interface fell victim to using BOTH a mouse input and a keyboard input. Now I'm not sure if hangman is the best use of VR, but I am certain there is a better option out there than having the player click on letters from a digital keyboard.

On the complete other end of the spectrum is a game called Fantastic Contraption, which was popular many years ago but recently ported to VR. In this game, every action you can take is about the physical space around you - switching between tools and items happens by reach with the motion-tracked controller to various parts of your body, and this makes it easy to remember where things are - "this tool is always behind my right shoulder." Fantastic Contraption also has an adorable "living" menu in the form of a cat that follows you around in the game. Have a look for yourself:

Another thing to keep in mind with VR is that almost any kind if input from the user's hand has the risk of feeling unnatural. If you are using the motion-tracked controller to place a digital hand over something and then pull the trigger to pick it up, many users feel unnatural because the shape and texture of the object they see does not match the shape and texture they feel in their hand.

One of my games addressed this by not using hands at all - every interaction is completely gaze-based. Not only does this eliminate the unnatural feeling, but it also plays on a common human fantasy of being able to alter the world with your mind - staring at things to make them explode. You can see the demo video:

Mobile games have faced similar mouse-and-keyboard tendencies, and have also come up with some inventive alternatives.

One of the first issues that comes to mind for me is when a game has the user tap on something to select it, and then tap somewhere else to move it there. This is a common interaction with a mouse, but on a touch screen it makes so much more sense to drag it across the screen to the new location, because that is how we would move things in real life.

Another issue on mobile which isn't a problem with mouse-and-keyboard is that if something is on the top-left corner (or top-right corner for left-handed users) then the user's hand will be completely blocking the screen when they try to touch it.

Some of the more intuitive interactions include the two-finger pinch and stretch to zoom in and out, which I believe may have been genius when it was first used. And that one must have taken a fair amount of pondering, because there is no comparable interaction with the mouse and keyboard - it was completely unique to the touch-screen.

Most interactions where you swipe across the screen are also fairly intuitive, especially when you swipe towards the edge of the screen to throw something away. There is a VR equivalent to this which you can see in Job Simulator where the user throws objects toward the edge of the space to discard them.

I think that part of the reason why we end up stuck in the situation of defaulting to mouse-and-keyboard controls is because the majority of games are developed on a computer using the mouse and keyboard regardless of what platform it will end up on, and sometimes it takes a while before the developer is able to test on the target platform, and by that time the developer may have already gotten comfortable with the controls so it is intuitive for them and they don't notice the problem. We might see this improve somewhat when VR developers can start developing their games while inside VR, a solution some of the bigger game engines are releasing.

So, next time you are developing for anything other than mouse-and-keyboard, here is a challenge for you. Before you make any interactions or think about any kind of input, first think about what things are going to happen in the game - what is the in-game player going to do - then imagine yourself using the target hardware, or go and use it with nothing running, and imagine making those in-game interactions. Go ahead and pick up a blank phone or put on a dark VR headset, and close your eyes, and feel the interaction with the hardware.

Thanks for reading! Feel free to leave thoughts and suggestions in the comments - especially if you have examples of interesting interfaces for interesting hardware (both good and bad). Also subscribe and follow :)

Interface Design and Unusual Platforms, Part 1

I'm going to do something a little bit different today. In a couple of weeks I'll be going to Unite LA (the big Unity3D conference) as a speaker, and my talk is on Interface Design for Mobile and VR (and other unusual platforms). I've been trying to work on my talk, but I keep finding myself with writer's block, and I think I find it easier to blog that to assemble a presentation, so I'm going to jot down my ideas here. Feedback is welcome :)

I'd like to start off with an overview of unusual hardware, and specifically give some examples of how I've designed for some of them. Then I will move on to talking specifically about designing interfaces.

In no particular order, here is a list of all of the variety of hardware I can think of (and I have developed on each of them): Mouse, keyboard, gamepad, motion-tracking controller, head-tracking, touch-screen, Kinect, Wii balance board, heartrate, 3D stylus (zSpace), 360 treadmill, Leap Motion. You may notice that some of these are a type of hardware, whereas others are a specific brand. That is because I am lazy, and also some types of input are recognized more for one brand than for the type of input. Think of it like saying "Kleenex" instead of "facial tissue". People know what you mean.

Mouse, keyboard, and gamepad are probably the most common input people think of when they think of game development, so I am not going to talk about those. As I talk about each of the other types of hardware, I want to emphasize that my intention with design is to answer this question: "What is unique about this hardware that no other hardware can do?"

Let's start with the zSpace, the one you are most likely to have never heard of.

The zSpace is a semiholographic display tablet with a 3D stylus, and special glasses that has markers on them to allow the display to be projected toward you, giving a full 3D effect. Without actually using one, it can be very hard to imagine, so you will just have to trust me that when you use it everything you see looks completely real. Not "real" in the sense that it is photorealistic, somethings are very stylized, but real in the sense that you believe you could reach out and pick it up, like a toy.

When I was first presented with this device I had a team of artists and programmers working with me, and the only direction we were given is "this device is used for tools, education, training, and medical applications, see if you can use it to make a game." And so we set out. We began by orienting ourselves to the hardware, using the existing apps, then building some prototypes. We were looking for "fun" in the interactions, but we were also looking at what made it really unique, and very quickly we discovered both in the form of "drawing" 3D shapes using the 3D stylus. In particular, drawing spheres was very satisfying and enjoyable. So how can you make a game about drawing spheres? In parallel with our experiments, we had also been brainstorming game concepts, and had mostly sittled around the idea of having floating islands (to make full use of the 3D effect) that had bunnies on them, and the bunnies were being hunted by foxes. So as the player, your goal was to keep the bunnies safe. We tied this to our sphere-drawing mechanic by having the player draw bubbles around the bunnies to make them float up out of harm's way, and they would float over fenced in safe-zones where foxes couldn't reach them (there was also a small random chance of the bubbles blowing away in a wind gust, to add anticipation). In addition to bubble drawing, the player could also use the stylus to pick up items - a carrot to lure the bunnies, a stick to pop bubbles, and a fan to move bubbles around. In the end it was pretty enjoyable, but there was one thing missing...how to represent the stylus in the 3D world in a meaningful way? That answer came from one of our artists, who decided to make a pair of chopsticks. It did the trick of trying all of our interactions together. See it in action here.

Next up: 360 Treadmill. This is in essence a treadmill where you can walk in any direction while staying in place.



A couple of years ago I worked as a developer for Virtuix Omni, one of the first of such devices. What makes this hardware unique is pretty obvious, the input is which way and how fast the player is walking. It is actually similar to input from a joystick on a gamepad, so it translates fairly well to most first-person experiences. The big difference is that you are physically walking, and it is usually accompanied by a VR headset, so it gives you full immersion into your experience. My first thought, which a lot of other developers have also thought for VR, was virtual tourism. I think it is a bit more compelling on the Omni than in seated VR because the Omni lets you walk around the virtual destination. I did try to set mine apart a bit by thinking about what we usually do when we travel - we take pictures. So I made a virtual tour of Amsterdam where the only interactions are walking and taking pictures, and those pictures (screenshots, in this case) are saved to your computer so you have them to keep when you return from your virtual tour. You can check it out here.

Now for a real treat: the Wii Fit Balance Board!



The Balance Board is a pressure sensor (or multiple pressure sensors?) that can very accurately tell which way you are leaning. When you first stand on the board it asks you to stand still (that's right, the board talks to you) while it calibrates to your weight. After that it can tell any direction you lean based on where you are putting pressure. If you pick up one foot and step forward or backward, it know which foot and if you stepped forward or backward with it (based on the foot still on the board placing more pressure on the toe or heel). I have tried unsuccessfully to trick it, it's a pretty smart board!

While in grad school I was assigned to a team working with the U.S. military to design a fitness game. Obviously a mouse and keyboard was not going to work for this, so we set out to try all of the hardware we could find that was used for fitness games. We experimented with phones, PS Moves, and devices that track biometric feedback, before settling on a bizarre combination - we decided to pair the Balance Board with a Kinect to track both shifting weight and also upper-body movement. Oh yeah, and we added in a heart rate monitor :D

Here's how the game worked - we used used two balance boards so that two players could control hover boards in the game by leaning to steer. With their arms they could reach out to collect things or punch to "fire" a projectile (a ball of plasma that would come rocketing out of your fist). We also strapped heart rate monitors onto the players, partly because we needed the data, but we also decided to add a gameplay element around them. When the players step onto the balance board we took an initial heart rate reading, then as the game progressed and a player's heart rate went up we would make that player's plasma balls bigger and more damaging. The game was cooperative, so the two players worked together to fight off giant robot spiders, but at the end we gave them a score that combined how many spiders they kills and how many items they picked up. A fascinating thing happened when we added the heart rate effect - it actually evened out the scores between players who were more fit and less fit. Since we were taking an initial reading and tracking increase, players who were already in good shape had to work harder to get the positive effect. We found through testing that this leveling of the playing field made the game more fun for everyone. Want to see a gameplay video? Of course you do.

I really want to tell you about the rest of the hardware, but this post is now fairly long and I need a break, so I will continue in part two! Also, this seems to have done the trick to beat my writer's block!

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Continue to part 2.

The Making of Cat Cave

Cat Cave was my second self-published title, but it was actually a lot of first for me. It was my first endless runner. It was my first 2D game. It was the first time I formed a team to work on one of my ideas (I found an artist, a sound designer, and a second programmer). It was the first time I attempted a port to iOS. And the second release of Cat Cave was the first time I took promotion really seriously.

I've learned a lot from the games I have released so far, but I think the most valuable thing I have learned is you can never do too much work when it's something you care about. As a single cat mamma, I have no human children, and no husband (or wife) to take care of, so my games are really like my children - I look forward to leaving work in the evenings so I can go home and spend time with them. And I feel guilty any time I have a spare moment that I choose not to spend with them.

To some this may seem like an unhealthy obsession, but for me the things I make are the strongest justification for my existence.

In total, I estimate that I invested around 120 hours into the development of Cat Cave. I wish I had kept more thorough track, but I believe the breakdown went something like this:

• First Release
• Development - 30 hours
• Project Management - 10 hours
• Promotion - 10 hours

• Second Release (Major Update)
• iOS Port - 15 hours
• Development - 15 hours
• Project Management (including running beta test) - 10 hours
• Promotion - 30 hours

Another valuable lesson I learned is the importance of building hype. Don't release your game the day it is finished. And don't wait until it is finished to start talking about it. Talk about it all the time while you are making it. Pick a tentative release date far in the future. When you finish your game, get everything confirmed, and get it approved by all of the powers that be, THEN confirm your release date at least several days in advance. Then you must WAIT. Don't do anything to break the game. Don't do anything to put it in jeopardy on whatever platform you publish to. Don't let your anxious fans convince you to release it early. Just wait. And keep talking about it.

Speaking of which, here are the download links for Cat Cave, which is now available on Google Play and iTunes!

iOS: https://itunes.apple.com/us/app/cat-cave/id1104696928?ls=1&mt=8
Android: https://play.google.com/store/apps/details?id=com.Astire.CatCave
PC: https://moarkitties.itch.io/cat-cave

Thanks for playing!