Figure 1. Concept art for Arizona Sunshine*.
With a dazzling launch in early 2017 that saw Arizona Sunshine* become the fastest-selling non-bundled virtual reality title to date, and instant recognition as the 2016 “Best Vive Game” according to UploadVR, the zombie-killer game is not just another VR shooter. Combining immersive game play with intriguing multi-player options, this game takes full advantage of VR capabilities to promote playability in both outdoor and underground environments.
Through its association with Netherlands-based Vertigo Games and nearby indie developer Jaywalkers Interactive, Intel helped add sizzle to Arizona Sunshine by fine-tuning the CPU capabilities to provide end-to-end VR realism. The power of a strong CPU performance becomes apparent with every jaw-dropping zombie horde attack. From the resources available when a player chooses and loads a weapon, to the responsiveness of the surrounding eerie world, the immersive qualities of the VR interface make it easy to forget that it’s just a game.
In recent years an influx of exploratory games and experiences designed to keep up with the new wave of VR titles have hit the marketplace. With these new experiences comes the complexity of ensuring a perfect mix of CPU and GPU power to provide the level of realism that is expected within VR. Several features in Arizona Sunshine provide this level of immersion. Following Intel’s Guidelines for Immersive Virtual Reality Experiences, the features break down into three key categories:
- Physical Foundation
- Basic Realism
- Beyond Novelty
This paper highlights how Arizona Sunshine—built exclusively for VR systems—has benefitted from adherence to the Intel guidelines.
Mission Overview: Kill the Zombies
When Arizona Sunshine starts, the unnamed lead character awakes in a sheltered cave, safe from the scorching post-apocalyptic desert heat. He soon hears a radio transmission and realizes that other humans are alive, and they’re also battling for survival against the zombie horde. As he sets out to find help, the story arc is set.
While game action takes place in the desert heat and underground in an old mine, the goal is the same: survive and find a friend. The lead character offers quips and asides as he fights his way through the room-scale VR, using a teleport system and motion-controlled weapons to pace him through bite-sized chunks of action.
Figure 2. From the bright Arizona landscape to dark, underground mines, Arizona Sunshine offers plenty of targets.
Game play is enhanced whether playing on an Oculus Rift* or Vive VR System on the PC, or on a Sony PlayStation* using the PlayStation VR Aim Controller. Players learn to squint through one eye to aim as they progress through 25 weapons, from pistols to assault rifles. Campaign mode is a standard shoot-fest where players can play alone or with others, and the ultra-engaging Dynamic Horde mode is where players slaughter numerous zombies, either with friends or alone.
When powered by at least an Intel® Core™ i7 6700K processor, Arizona Sunshine really packs a punch. Continual enemies in a complex, interactive environment bring unprecedented realism to VR gaming with zombie destruction, rich environmental elements, and a cinema-quality playing field. The AI is simple, but ruthless, and if a zombie gets close enough, it can flail away, masking a good, clean head-shot, while it tears players to pieces. The custom-built animation system makes getting in a good kill shot as satisfying as anything else in the VR universe.
Intel’s New VR Guidelines Provide Key Guardrails
As with any new technology, a new VR game might seem fine at first glance—and great to own simply because so few choices exist. But deeper into game play, players may find the title contains fatal flaws that cause them to drop the game. Because VR has already been studied in detail, and with more research continuously available, those flaws are avoidable.
Intel has expended a significant usability testing effort to extend VR research and to extrapolate some basic rules. So far, researchers have observed players’ initial and continuing experiences with a variety of VR activities, followed by detailed debriefing sessions and questionnaires to discover the specific factors that made the experiences enjoyable. One key finding was a high statistical correlation between enjoyment and the level of immersion. The research also revealed several aspects of the games and environments that closely correlated with immersion and are, therefore, keys to extending that feeling.
Figure 3. Head underground and Arizona Sunshine immediately welcomes players with echoes, faint noises, and swarming zombies.
The following guidelines are condensed from Intel’s Guidelines for Immersive Virtual Reality Experiences and are described in relation to Arizona Sunshine.
Physical Foundation—Safety First
The first rule for any VR game is safety. Because VR players are wrapped in a headset and may forget the limitations of their actual environment, laying a safe physical foundation is crucial. VR games make immersion possible by using technology that keeps the player safe from injury while wearing a headset, comfortably free from soreness due to hardware ergonomics, and free from motion sickness. Players must not be distracted by unrelated sights and sounds from the outside world; otherwise, the immersive aspects are dashed. Worrying about safety while fighting off zombie hordes is not an option—players must be free from concern in their physical space.
As players are initiated into Arizona Sunshine, they quickly notice several features that keep them safe and free from dizziness:
- Swift teleportation. Movement in the game is a pain-free and seamless interaction. When players choose to teleport, the game provides four different directions that allow for precise movements around each scene. Players feel like they are traveling through the virtual world without running into objects in the physical world.
- Zero latency. Players should detect a welcome lack of latency when teleporting, interacting with objects, and even unloading their weapons. Every movement that players make is swift and natural-feeling. Using the most powerful gaming system is crucial to maximizing the VR experience; optimizing the processing load between the CPU and the GPU is crucial, and made possible by powerful Intel tools such as Intel® Graphics Performance Analyzers. At times, the scrupulous attention to detail in Arizona Sunshine means that reloading in the middle of a fight is just as time-consuming in the game as it is in real life, even without latency issues.
- Appropriate use of space. As players move in the game, they should notice that distances match what they would be in the real world. For instance, if they drop ammo on the ground, they must physically reach down to the ground to grab it.
Figure 4. Battling underground provides a realistic sense of confinement and entrapment.
Basic Realism Depends on Potent Sound Effects and Visuals
To be successful and fully immersive, Intel’s guidelines stress that the virtual world should seem real by providing smooth 3D video, realistic sound, intuitive controls for manipulating the environment, and natural responses to the players’ actions in the virtual world.
These concepts are an integral part of game play in Arizona Sunshine; the VR environment and sounds are realistic and responses to players’ actions are genuine.
Although the level of realism throughout Arizona Sunshine is a pleasant surprise, it’s the avalanche of shambling zombies that exponentially boosts the “fear factor.” The underlying interactions and feedback of each object feel captivating and build the realistic sensation to the game. These key features add to the realism of Arizona Sunshine:
- Responsive destruction. The game has an overwhelming amount of realistic destruction. As players battle with the zombies, they soon realize that accurately killing them is heavily reliant on skill, rather than just spraying bullets and hoping to hit a vital spot. Based on where the player shoots the zombie, as well as the distance of the shot, the zombie body parts react and destruct appropriately. For example, shooting a zombie in the head at close range causes it to perish, while shooting one in the leg keeps it alive with only the leg itself detached. Similarly, instead of opening cars or going through doors, players can simply destroy the windows and door knobs with a well-aimed shot from their weapon.
- Responsive world. From the billboards to the deserted huts on the ground, almost everything in the virtual world is responsive. The zombies take that responsive element to another level. During combat, merely hiding from the zombies by locking oneself in a shed may be the best tactic. The zombies naturally react to this by attempting to break down the door but then go away after they are unsuccessful. In this way, the game responds to the players’ tactics. The player feels engaged as the main character and not controlled by the game’s assumptions.
- Haptic feedback. “Haptics” refers to the systemized sense of touch in a game to provide important information to the player. Arizona Sunshine does a great job at relaying its own haptic language to communicate certain patterns. For example, when the player is getting shredded by a zombie, the controllers shake in response, providing important feedback that heightens the sense of danger. Similarly, when the player dies, the virtual world turns green and the controllers shake to indicate a fatality.
- Visual feedback. Initially learning which items in the rich environment can—or even should be—interacted with, takes practice. As players approach any object, a glowing circle appears as an invitation for interaction. These visual clues are an important part of the learning curve, providing a boost to productivity before a player starts to feel like giving up hope of conquering the undead army.
- Basin of attraction. In physics, this is where a collection of all possible initial conditions in a dynamic system converge on a particular attractor. The game uses that concept to help the player complete simple tasks without failure. For example, holstering the gun or placing ammo on the player’s belt can be done by mimicking the action of bringing the objects close to the desired destination.
- Realistic sound. Using the Doppler Effect, the game provides excellent realistic sounds based on the distance and mass of objects. For example, as zombies approach, the player can hear the progression in their screech volume. Other natural sounds, such as water waves, crickets chirping, and wind blowing add to the realism as players navigate the world. Adding such realistic effects greatly enhances the immersive quality to Arizona Sunshine. When sounds are faint, it’s because they should be faint—enemies cannot trick players by suddenly materializing in a break of the time-space continuum.
- Responsiveness to player movements. As players enter each level and reach different checkpoints, several unique visuals and audio elements respond to player movements. For example, when players look through tinted windows, the visuals appear darker.
- Responsive sound. During several moments, the virtual world responds to various sounds that the players initiate. For example, when firing a gun or making loud movements, the zombies react by swarming to the player’s exact location. Enforcing stealth in the game can result in players actually holding their breath, a good sign that the game’s interface is working as intended.
Figure 5. The ubiquitous zombies are programmed to swarm and are attracted to players’ noises.
Beyond Novelty—Do Something New!
Being first at something isn’t enough for a game to succeed. Merely developing VR aspects in a dull game means it’s still, at core, a dull game. Arizona Sunshine solves this dilemma by providing a main character that players cheer on and want to make successful. This provides a story arc that players can follow to propel the main character to a satisfying conclusion while he interacts with players through sarcastic asides that often mimic exactly what the player might be thinking.
To keep the immersion alive and engaging—rather than merely impressive—developers should mimic reality by enabling interaction with nearly everything in the virtual world. This offers good game play that is independent of technology, making VR interactions core to the experience and easing the player quickly and smoothly into the virtual world.
Because Arizona Sunshine offers tough challenges and an interesting storyline, players engage in their mission and are willing to do anything to achieve it. Two key features enable this level of immersion:
- Ubiquitous interactions. Throughout the game, players find that the virtual world respects their ability to interact with the playing environment and allows for interaction with almost every object. For example, unless the object is locked, nearly everything with a handle can be opened and closed. The downside of this feature is that a creaking hinge or a squeaking door knob could be the tiny noise that brings the zombie horde immediately to the player.
- Captivating interactions. Aside from ubiquitous and constant interactions, the game also provides realistic challenges that capture the player’s interest and evoke unexpected emotion in almost every scene. For example, a player might innocently pick up a grenade, which could set off a fiery explosion. This not only heightens the sense of danger but also injects a dose of adrenaline and subsequent pragmatism to heighten playability.
Follow the Rules, Reap the Rewards
Arizona Sunshine embraces Intel’s Guidelines for Immersive VR Experiences and genuinely delights players in its post-apocalyptic world. By following Intel’s basic guidelines, the game is more than just an early VR success; it is a blueprint for future designers. Simply porting yet another zombie shooter might guarantee some level of profitability, just by being early to market. To truly turn heads, Arizona Sunshine stays simple in approach but complex in implementation; and it takes full advantage of the technology available. When played on powerful Intel gaming systems that are optimized to balance the load between processing and graphics, the result is an immersive, addicting first-person shooter game that shines as a great example of harnessing the power of new technologies.
About the Author
Hope Idaewor has been an intern with Intel immersive user experience team, and currently a student at Georgia Institute of Technology.