One of the most important tools for accessible design are captions and subtitles. Captions connote text appearing in the same language as spoken dialog while subtitles usually refer to text translated into a different language than the spoken dialog. These tools assist a wide set of audience members, from those experiencing hearing loss, those with cognitive disabilities, those who speak different languages, to general users who prefer to read dialogue rather than listen.
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Unfortunately, there is no universal font for captions and subtitles. In fact, industry guidelines recommend you provide several fonts and enable users to select from a variety of fonts to meet their needs. Industry guidelines recommend serif, sans serif, mono spaced, along with a few others. However, as a general rule, sans serif fonts (fonts that don’t have serifs or extending markings at the ends of the characters) can be more legible than serif and stylized fonts.
You can also consider fonts like OpenDyslexic, Arial, and Comic Sans that are easier to read for people with dyslexia. It’s always recommended to have caption and subtitle functionality but these are more accessible and effective if users can select their preferred font.
Caption font size should be customizable to match the user’s visual ability. It’s generally recommended to include three settings for font size:
If resources allow, additional customization options would improve your app’s accessibility even further. For 2D media, it is recommended to set your font size to take up about 10% of your screen. For VR applications, font sizing can vary depending on whether you enable users to move the location of the subtitles closer or farther from their viewpoint. We recommend using 10% as a baseline and tweaking the size as needed based on user testing.
There are many vectors to consider when setting the location of your captions and subtitles. While we always recommend providing people the option to move the captions closer or farther, in general you can spatialize them about an arms length away from the user in virtual space. Again, you can use this distance as a guideline and edit it as needed per your playtests, but this distance is generally enough to give the user a sufficient amount of space while maintaining a legible distance.
If you would prefer to avoid placing your captions at a fixed distance from the user, you can explore other options like speech bubbles, placing the text above or below characters who are speaking, or any other design options that align with your app’s look and feel.
It is also important to explore options for movement such as whether the subtitles are head-locked, meaning they move as the user’s head moves, or whether they are locked in space, meaning they stay in a fixed location. We recommend a combination of both. When subtitles are locked in space, they can be used to focus the user’s attention. However, when they look away, you might render a small arrow or visual cue directing them to the main event/caption. This enables players the agency to explore the space while still retaining the captions and subtitles in a legible location. This also allows you as the developer to have more control over the user’s attention and how the subtitles will appear within the scene.
As different applications will have different design and accessibility needs, we highly recommend that you experiment with different locations and movement options for captions and subtitles. Throughout testing, ask yourself, do my captions cover any important visuals? Are my captions too far away from elements that should get the user’s attention? Will I need to move or rotate in an uncomfortable way in order to read my captions?
Feel free to share insights and learnings from these experiments in the Accessibility category in the Developer Forum so that others might learn from your implementations.
To ensure that people who require captions and subtitling have a similar experience to those who do not, we recommend either displaying the words in unison with the dialogue or displaying complete sentences as they are spoken. Make sure the sentences are provided in easily understood blocks, such as 2-3 sentences at a time, and allow pauses where they are required for either dramatic tension or to simply give readers a break.
To fully utilize the 360 space, consider using visual indicators, arrows, or any other objects/signals, in addition to audio, to direct players towards the source of a sound or next game event. For example, add arrows that point toward the character speaking or onomatopoeia (e.g. cuckoo, bam, sizzle, etc.) accompanied by arrows to show where an object crashes in space. Visual indicators can also point users towards where they should pay the most attention to in order to fully understand the narrative.
Tricks to drive focus are key in virtual reality storytelling and even more so when sound is not an option. As you design for VR, consider how these narrative cues contribute to the overall experience, and imagine how the user would feel if they were progressing through the experience without one or both of them. If you can add visual cues to help the user locate audible events in the 360 world, the user will have an easier time navigating and understanding your experience.
Try playing through your experience while relying on captions and visual cues alone. Are you still able to properly experience the full narrative? If not, consider redesigning these aspects for additional clarity and a more complete experience.
When choosing caption and subtitle colors, the most important factors are contrast and legibility. On most platforms (films/television, 2D games, etc.) lighter colors are preferred because darker tones and black are displayed more frequently than large planes of white and other lighter tones. Hence, lighter colored font for captions and subtitles has become the industry standard to ensure user legibility.
You can still use darker tones if you feel it helps improve legibility for your specific content. However, we highly encourage testing the subtitles and captions before launching your application. Try playtesting your game without any audio with someone who has never seen it or has no insight into the interactions/storylines. Can they still figure out the mechanics just by reading the captions? Did they generally understand your narrative? Were they able to read what the character was saying?
Regardless of the color you select for your captions, you should always consider having an outline or text background box to separate your captions from the environment. Especially in VR, players could miss your captions depending on where they are focused at the time and where they are within the space, and drawing more attention to them will help users more effectively move through the experience. To ensure a balance of user needs, we recommend providing some sort of custom settings for text contrast and background color, this will help ensure your captions and subtitles are displayed for maximum usability and accessibility.