Name things, and write text in any language

This guide gives the models and groups that matter a name of their own (0.3), so that screen readers and the text view say what they are, and says which language a page's text is in and which way it runs (0.3), so that it is read in the right voice and drawn the right way round.

Give a model or a group a name

Without a name, a screen reader hears a model's id, or its file's name: "shark-1", "boulder.glb". A label names it in words:

<group id="tunnel-fish" label="Fish in the tunnel">
  <model id="shark-1" src="fish/shark.glb" label="Blacktip reef shark" position="-4 4 10" />
  <model src="fish/snapper.glb" label="Mangrove jack" position="2 3 6" />
</group>

• The name is what the outline of the scene lists ("Model: Blacktip reef shark"), what Tab reaches, and what the text view shows.
• A group with a label is in the outline even without an id.
• Name what a visitor would ask about: the fish, the exhibits, the doors. Walls, floors, and rocks can stay unnamed; a model without a name is still in the outline, by its id or file.
• A script can read and change a name: holoml.find('shark-1').label.

Say which language the text is in

Write lang on the root for the whole page, and on any element whose text is in another language. The value is a language tag, as in HTML: en, ar, he, pt-BR, zh-Hant.

<holoml version="0.3" lang="en">
  <scene>
    <label position="0 2 0">Welcome</label>
    <label position="0 1.6 0" lang="fr">Bienvenue</label>
  </scene>
</holoml>

An element without lang takes it from the nearest element around it that has one, as in HTML: a group's lang reaches every label in it. A screen reader reads each text in its language's voice.

Write right-to-left text

For Arabic, Hebrew, and other scripts written from right to left, give dir="rtl" with the language:

<group lang="ar" dir="rtl">
  <label position="-2 1.6 0">أهلاً وسهلاً</label>
  <panel position="2 1.5 0" width="1.2">مرحباً بكم في المعرض. هنا تجدون التماثيل الثلاثة.</panel>
</group>
<hud corner="top-right" lang="he" dir="rtl">ברוכים הבאים</hud>

• A renderer lays such text out from the right: a label's words, a panel's lines (each starts at the right edge), and the screen's text.
• dir="auto" lets the first letter decide, for text that may be in either kind of script, such as a name a script sets.
• dir is inherited as lang is, so a group in one language says both once.

Try it

• Open the text view (in HyperSpace 3D, its top-bar button), and read the names and the text.
• Turn on a screen reader, and Tab through the outline.
• The checker reports a tag it cannot read (en_GB with an underscore, an empty one) and a dir that is not ltr, rtl, or auto.

See also

• The specification: Language and direction, model, group.
• Put text in the scene and on the screen