Uncharted Territory #3: Using Diegetic UI in VR Games?

In our last Uncharted Territory article, we talked about how important standardisation is to an emerging industry. Which makes it very interesting when the virtual reality games industry seems to resist all attempts to standardize, as it does with locomotion!


As our explorations in VR movement revealed, sometimes this is due to VR’s unprecedented level of immersion and proximity, which means every user’s experience is so deeply personal and unique to them and their setup, that no one size will ever fit all.


Conversely, sometimes a design principle is so well-received that it does become the golden standard to hit—but the standard is too specific, or too complex, and the primary barrier to widespread adoption is just how dang difficult it is to pull off. Diegetic UI is one of those loved-by-all, understood-by-few topics, and one we’d like to shed some light on today.


But wait...what is diegetic UI? Despite its “buzziness,” is it a valuable design principle for games, let alone VR? If so, how do we practically apply it to our titles?


We’re here to help unpack all of that for you, starting with the basics!


Screenshot from virtual reality game DOOM 3: VR Edition, a Cyberdemon enemy towers over the player, illuminated by a flashlight. The player aims a futuristic gun at the enemy. There is a glowing interface on the gun that displays ammo.

What the heck does diegetic mean?


Diegetic is an odd-ball term that originated in ancient Greece, of all places (the root word meaning “narration”) and is generally understood as a film or theatrical term.


In films, the concept of diegesis helps to differentiate between elements of the film that appear in the literal world of the story, versus elements that exist only on the “meta” level, to enhance the experience of the viewer.


A still from the film The Lord of the Rings: Return of the King. In the final battle scene at the Black Gate of Mordor, the character Aragorn holds his sword high and charges into the battlefield of waiting orcs.

For instance, in The Return of the King (2003), when our hero Aragorn leads the heroic charge into battle, he’s accompanied by a heart-wrenching swell of soaring, orchestral music. It’s beautiful! But we as the viewers understand there isn’t a literal orchestra in the scene, sawing at their violins on the battlefield. The music exists in our imagined version of the story, not the literal cinematic world; it is non-diegetic.


A still from the film TRON: Legacy. In a futuristic club lit by TRON-like white lights, the members of the band Daft Punk play music from a disc jockey booth in the wall.

Conversely, in TRON: Legacy (2010), there is a scene where a fight breaks out in a dance club. The camera cuts conspicuously to a pair of disc jockeys (Daft Punk in their notorious cameo) who begin to play music from their booth as the fight occurs. It’s heavily implied that this music exists in the literal world of the film, and can be heard by the characters inside this club: the music is diegetic.


That’s all well and good when it comes to film, but how does diegesis apply to games? There are many answers to this, but one of the most common game elements designed diegetically is UI, or the User Interface.


Okay, cool. Now what the heck is diegetic UI?

For the sake of expediency, we’ll assume you have a foundational understanding of user interface (UI), especially as it pertains to the larger user experience (UX) within games. If not, here’s a slick primer to get you started!


To cement these ideas, let's take a look at a clever example of how UI can affect UX, which can be found in Red Dead Redemption 2.

A screenshot from the video game, Red Dead Redemption 2. Four cowboys ride on horseback down a snowy mountain ridge. In the lower left corner, a user interface element appears, displaying the characters' location in the world map.
A screenshot from the video game Red Dead Redemption 2, featuring a weatherworn signpost in a dusty canyon. It points to three in-game locations: Fort Wallace, Valentine, and Emerald Ranch.

If the player turns off the default “GPS-style” map-markers, suddenly NPCs start giving practical directions to locations as they might in the real world, and signposts that were once just set decoration are now vital to the player as they navigate the world as a 1890s cowpoke might. UI directly influences UX in a visceral, immersive way.


In some ways, those signposts become a type of diegetic UI, guiding the player to where they need to go without pasting a non-diegetic map to their screen. Neat!


Another famous example is Dead Space, where the player’s health is displayed as a literal bar on the spine of the player character, Isaac. This increases immersion by removing the need for a heads up display (HUD) while keeping critical information at the player’s fingertips!

A screenshot from the video game Dead Space. The player character, Isaac Clarke, fights a necromorph enemy in a broken-down spaceship corridor. The gun he is pointing displays the ammo count as a floating display, and a glowing bar on the back of his suit displays the player's health.

How does diegetic UI apply to VR?

Ever since the infamous “Exit Burrito” in Owlchemy Labs’ Job Simulator (players literally eat a burrito to exit the game, as opposed to navigating through a menu) diegesis has been a significant pillar of VR game design.

A gif of the virtual reality video game, Job Simulator. The player character opens a a suitcase to reveal a burrito that says "exit" on it in sauce. The player takes a bite from the burrito, revealing text inside the burrito that says "really?" They take another bite, and the scene fades away.

It’s important to note that, when we apply diegetic UI to VR games, the concept splits into two similar, but unique types of implementation: diegetic and spatial. For today, let’s define diegetic as meaning “actually exists within the game world” and spatial as “is displayed within the game world, but might not literally exist within it.”


Our underwater adventure game, FREEDIVER: Triton Down, gives us handy examples of both!


A screenshot from the virtual reality video game, FREEDIVER: Triton Down. The player character is holding a glowstick, and extends their arm to illuminate a wall carving. Various interface elements appear on the arm, including an oxygen meter and a mission display screen that reads "INVESTIGATE CAVE, Depth: 41 M""

In an effort to reduce the need for menus, the game makes heavy use of body-based inventory. UI elements such as the wrist-mounted oxygen meter literally exist within the game world, and are therefore diegetic.

Another still from the VR video game, FREEDIVER: Triton Down. A large menu board appears in the game world, hovering above the water of a lagoon. In the background, a ship that reads TRITON EXPEDITION on the side appears.

However, the big tutorial screen at the beginning of the game is technically displayed within the world, but does not literally exist in the world of the game. This makes it spatial.


For the record, we think both are neat! More specifically, both have their strengths and weaknesses, and their place within VR games depending on what works best.


The best path forward is to prototype and test until you find the solution that works best for your experience.


Ensuring that our UI remained helpful to the user without hurting immersion was a key design principle in FREEDIVER: Triton Down, and something we carried into our latest project, DOOM 3: VR Edition. (Hint, hint...more on that later!)


How does VR benefit from well-implemented diegetic UI?

Diegetic UI in "flat" games means the interface is integrated in the literal game world, which heightens the player’s sense of immersion. When applied in VR, diegetic UI takes that immersion one step further: it merges player, world, and interface, which in turn connects the player viscerally with the experience. Not only does the world become the interface, but the player becomes the controller.

A gif from the VR game, FREEDIVER: Triton Down. The player swims into a dark vent, pauses to light a glowstick, then places the glowstick on their arm so that they can continue swimming.

When that happens, the barrier between player and experience is wildly reduced, and immersion skyrockets. This is the fundamental promise of VR gaming, especially when it comes to RPGs and hyper-realistic simulators!


On a less conceptual level, it also helps to increase comfort, and pave the way for intuitive gameplay in a world that responds to the player’s impulses, much like the real world.


Designing diegetically in DOOM

As luck would have it, our latest VR title also happens to be a prime case study in practical design of diegetic UI and gameplay: DOOM 3: VR Edition.

Promotional key art for the VR video game, DOOM 3: VR Edition, featuring the Hell Knight enemy glowering over the game logo. Sparks and smoke appear around the enemy.

Earlier this year, we had the opportunity to work with the massively talented folks at Bethesda Softworks and id Software to bring their iconic DOOM title to PlayStation VR. As the VR adventure guides, our mission is to not only partner with the best teams in the biz, but to figure out the features their games need to be successful and fun in VR.


Here’s a look at how we tackled this amazing challenge...


Step One: Identifying requirements and roadblocks

When it came to DOOM 3: VR Edition, our priority was to bring the UI into VR while keeping the gameplay and overall feel of the original intact. The first step was to feel around the edges of the project, and identify the challenges we’d face when putting DOOM in VR.


The VR UI would need to...

A gif from the VR game DOOM 3: VR Edition. Standing in a hellish landscape, the player holds a shotgun and rotates it so they can better see the ammo display.
  • Maintain the core information required by players

  • Be easily accessed at any time

  • Not obstruct the player’s view

  • Be consistent

  • Be flexible for edge cases

  • Have a modern feel, but still respect the original vision

  • Surpass the expectation of long-time DOOM 3 fans

Step Two: Working with what you’ve got

Since DOOM 3: VR Edition is a PlayStation VR exclusive, we were able to quickly identify interesting challenges and opportunities presented by the hardware…

  • 270 degrees of tracking (not 360 degrees, or “room-scale”)

  • The seated experience needed to be as good as the standing experience

  • The trackable DualShock4 would allow for intuitive ducking, crouching, and independent gun movement

  • Using the PS VR Aim Controller would elevate immersion even more

A promotional image for the PlayStation VR Aim Controller, showing a player wearing the PlayStation VR headset, a pair of headphones, and holding the white Aim Controller like a gun at the ready.

Bethesda had also chosen the perfect DOOM title to adapt to VR. DOOM 3 is an action/horror game, with a relatively slow pace compared to the franchise’s modern entries. We knew that players wouldn’t be moving around at breakneck speeds, and the more gradual movement style would allow more room and flexibility while navigating the interface.


Step Three: Prototyping solutions

Rubber, meet road!


Once we understood what was possible with the hardware, and what the redesigned UI would need to achieve, we began to tackle the challenges and prototype solutions. (Let’s see how many of them turned out to be diegetic...)


A screenshot from the VR Game DOOM 3: VR Edition. The player reaches out with their hand to interact with a touch-screen medical station. On their wrist, a large watch-like device shows the player's health, armour, and flashlight battery.

An easy early win was the “wrist watch,” a deceptively simple feature that peeled the core information off the screen (ammo, health, flashlight battery, etc.) and packed it into an arm-mounted device. This kept the information handily available, even in the heat of battle, and helped to drive immersion.


Working from there, we also took the flashlight and placed it directly on the weapons, rather than forcing the player to select and hold it separately from their weapons.

A gif from the VR game, DOOM 3: VR Edition. The player moves through a poorly lit futuristic corridor, gun at the ready. An enemy appears nearby behind a flight of metal stairs, startling the player and forcing them to shine a weapon-mounted flashlight at the enemy.

This was a bit of a bold decision, given how it affects the tension of choosing between one’s weapons and the flashlight, but we aren’t the first ones to make it, and believe it was the right one for a VR adaptation.


The player must always come first; by placing the flashlight on the weapons (and adding a handy set of laser sights on top) we avoided cognitive overload for the player, and kept the experience fun, smooth, and intuitive.

We had the privilege of working with a world-class team at Bethesda Softworks/id Software (come on, they basically invented the FPS as we know it) and so were able to collaborate on these solutions until we had solid implementations in-game. DOOM 3: VR Edition is available now, if you want to check it out!


A screenshot from the VR game, DOOM 3: VR Edition. The boss enemy Sabaoth rises up to strike the player, who takes aim with a futuristic weapon.

Diegetic UI: A design standard to keep your VR train on the track

That’s just one example of the many decisions we had to make while adapting this game for virtual reality. As you can imagine, it might be easy to get overwhelmed, even if you’re making similar decisions for your own original VR game!


This is why standards and basic principles are so important: by prioritizing comfort and immersion, and understanding how a design principle like diegetic UI is so often a fast track to those core values, we were able to stay focused on making a great VR adaptation, and making intuitive, easily implemented solutions to decently complex challenges.


Now that you’ve unwrapped the mystery that is diegetic UI, and how it can be a strong compass point for your VR game design decisions, we hope you can consider it a helpful tool in your gamedev belt! (Or, if you’re a player, now you can be extra savvy when you see a bit of diegetic UI in your next game.)


A screenshot from the VR game Evasion. The player battles a flying robotic drone enemy with a futuristic gun. The gun conveys its ammo count with a diegetic display.

If you learned something new today, or have any questions for us, let us know over in the Archiact Discord! And don’t forget to stay tuned for our next installment of Uncharted Territory, this time taking a close look at another tool for your growing design belt, Emotional Design.