UX | Horizon Zero Dawn’s use of diegetic and non-diegetic UIs

During my review of Horizon Zero Dawn I touched on the way it uses different Diegetic and Non-Diegetic UI elements to communicate to the player what information is available to the player character Aloy and what information is intended for the player themselves. I quickly referenced it in my review as details about UI/UX is certainly not what people read my reviews for, so I’m taking some time here to expand on how Horizon Zero Dawn successfully uses details to both separate these UIs whilist fitting them perfectly into the universe.

HZD separates it’s UI into two distinct styles: One is Holographic and presented by an in-world item known as a “Focus” and the second is styled as cave drawing-esque chalk lines and is fixed the the camera. While we see plenty of titles that have utilised diegetic interfaces, Dead Space and The Division being the first to spring to mind, HZD is one of the only titles I can think of that blends the use of both so seemlessly. The information relevent to the Diegetic UI is relevent to the world and canon, only information that could possibly be handled by it in-world is presented, data such as analysis of in-world creatures whilst the Non-Diagetic UI handles all information that gamers are used to having, such as health bars, weapon selection and waypoints.

Aloy’s “Focus” provides the titles Diegetic UI. It is presented as a holographic spacial overlay in-side the in-game world. For those who are fresh to the idea of a Diegetic UI and Diegetic UI elements, these are pieces of information that are presented for the benefit of the player but exist within the game world. The way HZD separates this UI from the Non-Diegetic one by complete separating the stylisation allows the player to immediately know what information is known to the Aloy and is revelevent to the world she is in.

Tying such data into a in-game item allows for a much deeper explanation of how and why the player character knows things and how they’re able to achieve the things they can. Have you ever had to re-try a certain section of a game or puzzle multiple times until you got it right, the challenge of the section being more a matter of learning what to do rather than a matter of reflex or preparation? In the context of the game world doesn’t this raise flags of continuity? How did the character achieve this first time without fail? I find these occurances are damaging to the imesrsion of games; particularly those who emphasise story and engagement. Suspension of dis-belief is stilted somewhat if it’s simply not possible for a person to do or know something in a particular context. Inserting information like target weakpoints and information into a plot centric Diegetic interface simply and easily explains why the character can know this infomation in the context of the narative. I found this integral to Gurilla’s ability to craft a world and further draw the player into the universe; elements of the plot were actively assisting in gameplay and how the player had to think, the player is less a puppeteer sitting back and pulling the strings and more as a foot in the experience, sharing this UI with the protagonist.

This is in direct contrast to how the Non-Diegetic UI is presented to the player. With the stylisation being that of chalk and cave drawings the styling draws from the world that is being presented while giving the player a distinct separation between it and the holographic UI. Elements in this user interface focus around typical game UI elements: Control interfaces, Weapon selectors and ammo counters and interaction with the system. Whilst some of these, such as ammo count, could theoretically be handled by a diagetic tech-based UI, these elements are distintly not available to the player character in their graphical form.

Maintaining both user interfaces while keeping them so distincting visually separate allowed for Gurella to keep all world relevenet data still active and contextual to the game world, while still supplying the player a user interface that they’re used to and can immediately engage with. Gurella cleverly used a combination of these UI methodolies to further engage the player in the world that they were presenting, drawing then in deeper to the experience by having them co-op part of the UI side-by-side with the protagonist while not alienating traditional UI stylings and expectations by completely abadoning standard Non-Diegetic UI elements. Horizon Zero Dawn is a stellar example of UI design and worth a look for anyone with a passion for it.