Accessibility

Canvas graphics do not expose their visual meaning to assistive technology. Presenter.js addresses this with accessible descriptions that update as the current slide and build change.

Add description to a slide for its overall purpose, and to non-text objects that carry information:

import { Rectangle, Slide, Text } from "presenter";

const title = Text("Sign-Ups", {
  /* ... additional properties ... */
});

const bar = Rectangle({
  description: "First quarter: 200 sign-ups.",
  /* ... additional properties ... */
});

const slide = Slide({
  description: "A bar chart showing sign-ups for the past several quarters.",
  objects: [
    title,
    bar,
    /* ... additional objects ... */
  ],
});

Visible Text objects are described automatically from their content. Set a text object's description when the description of the text should differ from the visible wording.

Descriptions are collected in object order. Objects with opacity: 0 or drawn: 0 are omitted until they become visible, including objects in a group that is not yet visible.