Introduction

Interface generally refers to the interconnective boundary between different areas, spheres, or spaces, and is in human-computer interaction an established term used to define those aspects of a computer system that allow the user to interact with the computer. Human-computer interaction traditionally separates between a virtual software interface and a physical hardware interface, in which the virtual interface refers to the graphical user interface consisting of audiovisual features relating to menus and head-up displays, while the physical interface refers to the material hardware components such as controllers, mouse and keyboard, and display. As research on game interfaces is diverse and spans from media philosophy to computer science, there is no common definition to which all fields subscribe. This entry will provide a brief overview of some of the central debates surrounding interfaces in games research, and shortly describe some of the main areas of research on game interfaces.

Etymology and usage

The word interface is a composite consisting of the prefix inter- ("among, between, betwixt, in the midst of") and the noun face (appearance, expression, front of the head), which again is a derivative of the verb face (see, look) (Harper n.d.), and has been used in physics to describe "the meeting and metamorphosis of two structures" (McLuhan 1962, 149). In modern usage, interface is associated with communication technology where the term is used to describe the virtual or physical surface that allows for interaction between the user and the computer. Today it involves a number of technologies including gesture-based, tangible, voice-based, as well as graphical user interfaces (Preece, Rogers and Sharp 2015, 158). Likewise, video game discourse has traditionally differentiated between the physical interface consisting of game controllers and display, and the virtual interface consisting of the graphical user interface.

The physical game interface consists of hardware input and output devices such as game controllers and display, spanning a range of different input devices traditionally including keyboard/mouse and console controllers, to more recently mimetic interfaces, gestural interfaces, and output devices such as screens and head-mounted interfaces.

In video games, interface has traditionally been used to describe the graphical user interface relating to menus, head-up displays (HUDs), and pointers, but may also involve game system information that is visually integrated into the gameworld environment, such as names above character heads in the virtual world. Some would even consider in-world elements such as floating power-ups a part of the interface (Jørgensen 2013, 23, 154). There is a tendency in game studies discourse to distinguish such graphical user interface elements from the virtual gameworld environment, emphasizing the gameword as a fictive world to which the graphical user interface provides access. The influences of conventions from visual fictive media such as cinema and comic books give further weight to the understanding of digital game interfaces not simply as a relational tool for interaction, navigation, and control, but as a metareferential aspect that characterizes digital games as a medium.

Game interface design paradigms

Game interface design has been dominated by two distinct ideals; the first celebrates a subtle communication that presents system information to the player through inconspicuous and implicit means, while the second stresses a discernible style that communicates through unveiled and explicit information (Fragoso & Amaro 2017; 87; Jørgensen 2013, 7-10; Llanos & Jørgensen 2011).

The first approach adheres to the visual style of digital media that digital media scholars Bolter and Grusin call immediacy, which is a "style of visual representation whose goal is to make the viewer forget the presence of the medium" (1999, 272). This style is grounded in the idea of representational realism, which supports presenting the gameworld environment to the player pristine and untouched, uncontaminated by foreign or intrusive elements (Wilson 2006). This is an approach to interface design that avoids the use of overlaid menus and other forms of superimposed information and instead focuses on integrating the game information into the gameworld environment itself. Borrowing a term from narrative theory and film analysis, many scholars refer to such information as diegetic, indicating that it exists in and originates from the diegesis or storyworld of the videogame (see Galloway 2008, 941; Jørgensen 2010; 2013, 65-67; Waszkiewicz 2022, 40-41).

The second style follows what Bolter and Grusin call hypermediacy, which is a "style of visual representation whose goal is to remind the viewer of the medium" (1999, 272-273). This style prioritizes clear and efficient communication over a visual representation that is in line with a consistent and coherent fictive world, based in the idea that videogames are designed systems in which players interact through technologies that are not intuitive or automatically understood. On this basis, this approach stresses that the affordances of the game and the game environment must be communicated to the player through explicit means, such as through overlaid menus and monitoring systems, including Head-Up Displays (HUDs). Such information is also often referred to as non-diegetic or extra-diegetic, indicating that it does not exist within the fictional world of the game (see Galloway 2008, 947; Jørgensen 2010; 2013, 65-67; Waszkiewicz 2022, 40-41).

In practice, most game interface designers must treat these two ideals as the extremes of a continuum, spanning from game information that easily integrates into the fictional environment (such as using environmental features to indicate where the game space is traversable), to game information that breaks with the logics of a consistent fictional world (such as using overlay information to indicate how many lives the player has left) (Jørgensen 2013, 29-31). For this reason, most modern interfaces will to an extent be a hybrid between these two ideals, using the gameworld environment to provide clear information whenever possible but also augmenting it with extra emphatic information when needed. For most games this means adding a HUD, player-activated menus, and dynamic interfaces that show up in given situations such as highlights surrounding important object (compare Saunders & Novak 2006, 66) to support the player experience by ensuring that the player has access to all relevant gameplay information when needed. Further, the choice of interface style is also highly dependent on the genre and what needs the game in question has for providing relevant gameplay information. This means that a horror game may deliberately need an interface that provides little information to maintain suspense, while a competitive real-time strategy game may need to communicate precise and detailed information.

Example interfaces

An example of a game interface close to the immediacy ideal on the continuum is found in Alien: Isolation (Creative Assembly 2014). As a first-person perspective game, it allows the merger between the player's and the avatar's perspective, removing the avatar as visible vehicle in front of the camera. The game features a static interface consisting of a weapon and ammo indicator, and otherwise uses dynamic interface features such as overlay textual updates relating to quests and usable items. The player can also access certain menus relating to equipment and crafting. Taking damage is marked by a red filter on the screen. The most important informational tool of the game is a motion tracker that can be used to track the whereabouts of the alien monster, but it can also be tracked by listening to its movements in the ventilation shafts ([see figure 1]{.mark}). The example could be compared with the approach used in the third-person perspective game Dead Space (EA Redwood Shores 2008), in which virtually all information is treated as diegetic. The game has no overlay health bar, but visualizes the avatar's relative health level as a tube attached to the avatar's spine. Likewise, the inventory menu is shown to the avatar as an augmented reality interface floating in the air.

Fig. 1 – Screenshot of Alien Isolation.

A different approach that stresses representational realism, but not by sacrificing clear communication is the action-adventure game God of War (Ready at Dawn 2018). In this game, the default gameplay state offers a screen with only diegetic information augmented with a navigational compass, otherwise using environmental details (signifiers (Fagerholt & Lorentzon 2009, 52; Norman 2008; 2010, 89)) to signal different affordances, or possibilities for interaction, in the gameworld, and using context-sensitive overlays. For example, if a rock can be climbed, ledges and the presence of chains are used to signify this possibility, and dialogue is used to present cues and provide contextual information. Also symbols with a fictive status in the gameworld are used. However, certain interface elements are used for securing clarity, but draw attention towards the medium: For example, if the player draws a weapon, a minimal overlay HUD showing the weapon in question and a health/energy bar will appear. Also, if the player must use a designated button to carry out a particular action, such as pushing open a door, an overlay symbol showing the button in question will temporarily occur to signal this ([see figure]{.mark} 2).

Fig.2 – Screenshot of God Of War (2018)

An example that illustrates a game interface closer to the hypermediacy ideal is the real-time strategy game Crusader Kings 3 (Paradox 2020). Here all gameplay is based on the activation of different contextual menus and options from a complex HUD. The HUD frames the gameworld, represented by a map that uses dynamic highlighting to indicate which regions the player currently holds and which one they currently have activated. Diegetic information is scarcely used, apart from situations when the interfaces dealing with individual characters open, such as dialogue prompts or when selecting roles for individuals. In such situations, the diegetic information is quite limited, showing animated or still portraits, sometimes displayed in front of a scenery. The dialogue itself is also diegetic, but presented in text next to the animated or still character. In combat, the camera zooms in towards the map while maintaining a top-down view, showing oversized animated soldiers fighting, but they remain too large to be easily interpreted as diegetic. They are also accompanied by non-diegetic icons that indicate troop movement ([see figure]{.mark} 3). While real-time strategy games do not have an avatar that can be used as a proxy for communication to the player, MMORPGs such as World of Warcraft (Blizzard 2004) often also used HUD-based interfaces due to the need to micromanage several processes simultaneously, in particular in large-group raiding situations.

Fig.3 – Screenshot of Crusader Kings 3.

A hybrid approach is taken by the action-adventure open world game Horizon: Forbidden West (Guerilla Games 2022), which adheres to a graphical user interface style that combines augmented reality-style overlays with icons withing the geometry of the game environment, as well as a HUD showing health, weapons, and quest information, but frames it within the fictional context of the game. All interface is thus explained as part of an augmented reality interface available for the avatar, which allows for heavy interface use without compromising the idea of a coherent fictional world ([see figure]{.mark} 4).

Fig. 4 – Screenshot of Horizon: Forbiden West.

Game interface research

Research on game interfaces can broadly be separated into two main fields; digital humanities research, and human-computer interaction research.

Digital humanities-oriented interface research

The digital humanities-oriented research includes conceptual and ontological approaches (Jørgensen 2013; Therrien 2017; Waszkiewicz 2020; Willumsen & Backe 2015) as well as phenomenological and embodied approaches (Blomberg 2018; Farrow & Iacovides 2012; Grodal & Gregersen 2009). This area of research has also seen some research on the physical interface involving game controllers, typically from an ontological or embodied perspective (Willumsen & Jaćević 2019; Marcotte 2018), but focus has remained largely on the virtual or graphical user interface. A commonality of this research is that they discuss game interfaces from a philosophy of media standpoint, focusing on game interfaces on a conceptual level. Research typically involves the in between-ness of the interface in which questions deal with the status of interfaces with respect to the fictional world, what they represent, and what they can be said to be an interface between.

An overarching debate concerns the question of the delimitation and definition of the game interface. Is the interface restricted to superimposed elements such as HUDs and menus, or does it also include system information that is integrated into the gameworld environment, but which has no fictional status in the gameworld? Examples of elements that inspire such questions are health packs floating above the ground, question marks above quest givers' heads, and highlighting and frames that indicate important elements or current target. Other borderline features may be effects such as the screen turning red when the avatar is injured, or the use of sound effects used for informative purposes rather than for purposes of authenticity. Also, whether the avatar should be considered part of the interface is also a debated question (Jørgensen 2009; Klevjer 2007; Waszkiewicz 2020).

The answer to these questions is dependent on what we may understand the game interface to be an interface to. The idea that the gameworld itself should be considered part of the interface has also been postulated (Jørgensen 2013), bringing attention towards the idea that the game's visual representation as a whole -- here including both world environment and overlays -- may be considered representative of the game system, in contrast to the idea that the HUD and other system information represent aspects of the gameworld environment. The idea that all visuals represent the game system can be considered a system-oriented perspective on game interfaces, while the idea that the HUD represents the gameworld is a fiction-oriented perspective (compare Galloway 2008; Jørgensen 2013, 4-5). In this sense, this debate also connects with debates about representation and virtuality in videogames (Backe 2018; Klevjer 2017).

The discussions of the game interface also reflect the immediacy-hypermediacy ideals by debating whether game interfaces create a sense of alienation or defamiliarization from the fictional and narrative aspects of the gameworld (Walther 2007), or whether they should be considered a necessary disturbance and convention of the medium that results from the fact that they are user systems (Jørgensen 2013; Waszkiewicz 2022, 47). A prevalent debate is the meta-fictional element of game interfaces, relating to the idea that interfaces are an intermediary that provides information about the virtual environment and enables a player located in physical space have agency in the virtual environment. This positions the interface not within the realm of fictive elements, but neither as completely external to fiction, thereby giving it a quasi-fictional status.

Scholars have introduced different terms to describe different types of interface features, such as intraface (Galloway 2008; 2012, 39-40), transdiegetic elements (Jørgensen 2007, 74-76; 2010), and metaludicity (Ensslin 2014) while others have described them by using terminology developed for other media, such as the term metalepsis adapted from narratology (e.g. Barkman 2021; Ensslin 2015; Harpold 2007; Waszkiewicz 2022, 28-30). Others stress the self-reflexive (Gualeni 2016) or metareferential character of videogames (Backe 2018; Jannidis 2009; Waszkiewicz 2022). Some argue that videogames by definition are self-referential (Walther 2007), pointing to interface features involving situations in which system information breaks into the game's fiction, exemplified by avatars which address the player or HUD alerts indicating occurrences in the gameworld (Jørgensen 2009). Such situations are often referred to as the breaking of the fourth wall, or as an indication that games have no fourth wall (e.g. Conway 2010; Jørgensen 2013, 125; Waszkiewicz 2020; 2022), here using a theatrical concept that refers to the imaginary fourth wall separating the stage from the audience.

Human-computer interaction-based interface research

From the perspective of human-computer interaction, research on game interfaces tend to be experimental and thus focuses on how to make interfaces that enable players to better interact with the system. A characteristic of much of this research is that it does not attend specifically to the graphical or the physical user interface, but treats the total software or hardware prototype as an interface, reflecting the idea that the total gameworld representation can be understood as part of the interface (Jørgensen 2013). Thus, rather than dealing with the interface as a part of the system in a narrow sense, this research often deals with the affordances for interaction offered by the prototype.

Some of this research values the ideal of immediacy. This is often connected to the idea of intuitive or natural forms of interaction; or alternatively to the idea that such interfaces may support a higher sense of immersion and enjoyment. Examples of this is research on gesture-based game interfaces (Gerling et al 2010; Pirker et al 2017), mixed and virtual reality interfaces (Sra et al 2018; Rahimian et al 2014), and voice interaction in games (Allison et al 2018; Jung et al 2019). Another example is research on affective game interfaces, which aims to bring emotions and physical response into the design and evaluation of computer systems (Picard 2000). While some researchers focus on designing systems that can respond to emotion, for example face recognition software that can detect the emotional responses in the facial expressions of users (Lankes et al 2008; Obaid et al 2008; Sekhavat et al 2021), or biofeedback in which player interacts with the gameworld through controlling their physiological responses (Gilleade et al 2005), other researchers focus on designing games that engage through the emotions that they create (Isbister 2016).

Other research in this domain focused on accessibility and usability, and can thus be associated with the hypermediacy ideal in that functionality tends to be prioritized over representational realism. Examples of this is research on game interfaces for disabled people, such as game interfaces that allows for brain control (Lopetegui et al 2011; Mason et al 2004; Szajerman et al 2016; van Vlijt et al 2012), or auditory interfaces for the blind (Garcia & Neris 2013; Islam et al 2020; Mangiron & Zhang 2016). Also research that assesses the usability of game systems (Torpe et al 2019) and the practices of including usability in games among videogame companies (Rajanen & Tapani 2018).

Final words

Game interfaces is a topic that has inspired diverse research from multiple areas of research, which have approached the concept of the game interface from different perspectives spanning from conceptual, philosophical research to applied design research. This research is characterized by the diverse understandings of what the game interface is, and there is currently no shared comprehension across the disciplines of how game interface best can be defined and delimited.

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Citation Information

Jørgensen, K. (2022). Interface. In Grabarczyk, P. (ed.), Encyclopedia of Ludic Terms (Spring 2023 Edition). URL: eolt.org/articles/game-feel

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