VR Interface Metaphors

What are Interface Metaphors?

metaphor /ˈmɛtəfɔː/ noun
- a figure of speech in which a word or phrase is applied to an object or action to which it is not literally applicable.
- a thing regarded as representative or symbolic of something else.

The purpose of the Interface (UI) metaphor is to help users interact with the user interface more intuitively. It also lets users know instantaneously what those UI elements are meant to do. Metaphors are created to resemble physical objects but also have their own properties that are relevant to the technology they live in.

A good example of a UI metaphor would be desktop where the computer screen acts as person’s desktop with files and folders placed on it. Folders and files here are also metaphors that represent the file system of an operating system.

VR Interface Metaphors

VR is a rather new technology, and currently, there is no commonly established interaction methods for it — meaning VR interface metaphors are yet to be formed.

Using metaphors, users have to be able to interact with objects and navigate around. Some of the actions that can use metaphors include creating, deleting, editing, viewing, searching, navigating, organizing, moving, etc.

The challenging part here is to consider all unique digital possibilities that can exist (or co-exist) in VR. The list of interactions can span from using hands and gestures, eyes movement, voice control, to body movement and positions to interact. All of these can also expand further: gestures that tap, pinch, swipe, toss, throw, stick, etc. The technical possibilities also influence the interface objects: should menus resemble shelves, bags, watches, books, smart phones, or should they even exist at all?

Discovery around UI metaphors for VR would of course require a lot of research, testing what makes an intuitive and well understood method, and measuring how well accepted those methods are for the users.

For the UI metaphor to be widely accepted it has to be:

1. Well known among target users;
2. Have matching properties to their original physical representative;
3. Based on an activity or an object (or combination) to help users understand the ‘unfamiliar’;
4. Understood within the new digital environment.

Sources for UI Metaphors

Metaphors from pop culture

Pop culture, movies, literature, songs can introduce a number of metaphors that may be well accepted by users due to being well known:

• Hermione Bag (“Harry Potter”) — as a menu that can be carried around and contain an unlimited amount of items of different sizes;
• Wand — for various interactions that are not within the reach of the hands, or interactions that one would not normally do with their regular gestures;
• Howler (“Harry Potter”) — as a messenger.

Howler metaphor as a messenger

Metaphors from everyday modern life

Simulating everyday objects and actions can also make VR more real.

More specifically, architecture, interior or environmental metaphors specifically might be suitable for VR, because they would reside in the 3D space more naturally. Navigating in VR space with such metaphors would put a user in a more familiar environment, and thus make the new experience more intuitive. For example:

• Shelf — as a menu with objects, tools, colours, etc.;
• Purse — as a carry on menu or inventory;
• Tabs — as menu categories in the archived shelves or folders;
• Door / portal— as a portal to new experiences, or apps;
• Books / glasses / globes — these can also be portals to apps or experiences, especially with shelves as menus;
• Lab / work space / workshop / kitchen / office / library — as a space with an access to various objects, elements or experiences.

Glasses stand metaphor as a library of different apps and experiences

Metaphors from history

Each new era in human development introduced new discoveries, inventions and reforms which also had to be communicated and accepted widely at a time. Using similar metaphors might also be accepted in VR.

• Gathering, farming, crafting — for different types of accumulating objects;
• Stamp — for confirmation of sending / shipping;
• Trading, import, export, goods — for interactions with objects.

Farming metaphor as collecting objects into inventory

Conclusion

• UI metaphors let users understand interactions within the digital world, using their existing knowledge and experiences of the real world.
• There is a lack of UI metaphors in VR now.
• To create VR interface metaphors there has to be done research, testing if metaphors are understood, and measuring how well accepted those are for the users.