Apple has developed a new multiplayer AR game called Swift Shot, in order to demonstrate ARKit 2‘ multiplayer capabilities. People attending WWDC 2018 could get their hands on it and try it themselves. After the show, this game was downloadable for developers to experiment with.
I personally think it’s an excellent choice for a multiplayer AR game and let me explain exactly why? What general AR game design principles are implemented well in this specific AR game.
Before I begin talking about the AR slingshot game, let’s take a look how it plays in practice. The video made by VentureBeat.
Action and consequences – Observing an AR scene is a fun experience, but the fun begins where you actually get to interact with it and literally, make an impact. In the core of each game is an actionable act which, an interaction. Although this is part of the definition of a video game, in AR, I feel a more responsible and emotional connection with my acts to due to the fact that I impact things that seems to exist in my own environment.
In Swift Shot, I have the opportunity to make an impact in almost every piece of virtual object places in the scene, as the entire gameplay is all about displacing wooden-shaped blocks out of their original place. I get that immediate: “Oh, did I do just that” feeling that I rarely get in my daily life. Maybe unless I made something fall by mistake. Even then, it’s not a satisfying experience, because usually, I break something that shouldn’t be broken. In Swift Shot, I am psychologically set to be ready to impact things and I know there won’t be any negative consequences or it will cause any harm, on the contrary, it will actually be a fun experience.
This reminds me when I was a kid I built a tower of cards. Although the goal was to build the highest tower, the satisfaction came from enjoying the tower finally tumbling down. Same goes for making a long domino setup and watching the pieces collapsing one after the other.
Physical Interaction – the second thing that makes Swift Shot a fun game is a physical interaction. Now, I found that touch gestures don’t lead to an interaction that feels realistic. For example, if I want to get excited making a block tower fall down, I need to feel that I physically touch it. So in Swift Shot Apple used a pull-motion mechanic. The user pulls the sling backward by making a pull motion with the mobile device that forms a strong association between the body’s physical motion and the visual pulling action in as seen in the game.
Furthermore, now that physical motion can be straightly connected to what’s comes up next, and this is the feeling of tension (they used good sound effect for that) and feeling of force that you can correlate with its upcoming impact. That correlation gives helps associate your physical activity with the impact and the destruction you deal with the blocks and better connect the physical motion with the consequences that happens on the screen, virtually. So although you are not touching the blocks physically with your hand, it still creates a strong feeling of responsibility and emotional connection of what happened in the virtual scene.
Real-world Physics – the game employs realistic physics (at least as far as I observed it). This means that the game uses a realistic gravitational force. This leads to the user can already estimate the damage, and feel it, before the projectile was even released. This leads to an excitement of no just shooting the ball, but anticipating its impact. due to our own experience in life with blocks, we can already project and feel how our action will affect the blocks in front of us. Aside from already knowing the results of our action, this helps us apply tactical thinking to how we play it, so we won’t expose our slingshot towers and try to destroy obstacles that prevent us from getting a direct hit on the opponent’s tower.
Simplicity – Swift Shot is designed to be very accessible and easy to learn. Although it was designed to demonstrate the core “Shared Experience” multiplayer functionality, it doesn’t mean that a similar game should be more complicated than that. In fact, this is one of those game that anyone can play, even 4 years old can enjoy playing it and not feel overwhelmed by it and still feel that he or she has the same chance of winning.
Clean UI – Obviously Apple follows its own AR design guidelines. Swift Shot features very clean UI with only the lives an ‘X’ exit button on the screen. Playing an AR game through a screen does have a negative impact already on the experience due to the limited field of view and the focal length difference compared to how our eyes perceive it. To make the AR experience shine through we need to experience the scene as it was a seamless part of the real scene. To make it as such, it’s therefore advised to make more space for the actual scene to shine through than having lots of UI elements that can just impair the visual experience.
Good use of the vertical space – Swift Shot has a good level design with block towers that help defined the 3D space of the game and enhance the sense of depth. Furthermore, due to this design, the user is required to play it as he viewed the scene from a certain angle. So instead of experiencing the game out flat from a bird’s eye view, he or she can observe its three-dimensional design. This also further enhances the experience as the user change angles and sees the 3D scene from different angles, further improving the sense of depth. Furthermore, the use of textured surfaces for the wooden blocks also improves the sense of a 3D object’s depth.
Good choice for player positioning – The other player appears to be behind the blocks as it should be. It might not be so obvious, but in AR, the virtual content appears on the screen and as for right now, ARKit doesn’t have occlusion. So if the opponent was interacting with the game while physically positioned on the side, it could have ruined the perfect illusion of making the blocks appear like they are “physically” placed on the table. Apart from that, this player positioning allows them to see each other and their reaction through the screen as they play, which further enhanced the experience. The goal of the game seems to be built with that in mind as well.
Positioning players one in front of the other also promotes a more competitive and personal match, compared to the player standing right next to you.
Promotes Physical Movement – Swift Shot promotes physical movement, starting from the pull and aim mechanics and the fact that this game is best played from waistline height and up. You probably could play it on the floor while sitting, but it’s obviously more comfortable to play it as shown in the event, on a table, rather than on the floor. By the way, I’ve seen some devs posting some of their own gameplay videos, and like in many AR game, you also have the option to resize the game and fit it on a very small space (example).
Overall, Swift Shot, although a simple ARKit 2.0 multiplayer AR game, can give us a good look at some good game design practices. These AR game design principles are useful for any type of AR game but might inspire you to give them more attention when designing your next ARKit game.