Abstract

Assistive technologies need semantic information about the structures and expected behaviors of a document in order to convey appropriate information to persons with disabilities. This specification defines a WAI-ARIA 1.1 [WAI-ARIA] module of core roles specific to web graphics. These semantics allow an author to express the logical structure of the graphic to assistive technologies. Assistive technologies could then enable semantic navigation and adapt styling and interactive features, to provide an optimal experience for the audience. These features complement the graphics and document structure elements defined by HTML [HTML5] and SVG [SVG2].

This document is part of the WAI-ARIA suite described in the WAI-ARIA Overview.

Status of This Document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.

This is a Working Draft of WAI-ARIA Graphics Module 1.0 by the SVG Accessibility Taskforce, a joint task force of the Accessible Rich Internet Applications Working Group and the SVG Working Group.

Feedback on any aspect of the specification is accepted. For this publication, the SVG Accessibility Task Force particularly seeks feedback on the following questions:

To comment, file an issue in the W3C ARIA GitHub repository, using the "graphics" label in the issue. If this is not feasible, send email to public-svg-a11y@w3.org (comment archive). Comments are requested by 30 September 2016. In-progress updates to the document may be viewed in the publicly visible editors' draft.

This document was published by the Accessible Rich Internet Applications Working Group and the SVG Working Group as a Working Draft.

Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This document was produced by groups operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures (Accessible Rich Internet Applications Working Group) and a public list of any patent disclosures (SVG Working Group) made in connection with the deliverables of each group; these pages also include instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

This document is governed by the 1 September 2015 W3C Process Document.

1. Introduction§

This section is non-normative.

WAI-ARIA is a technical specification that provides a framework to improve the accessibility and interoperability of web content and applications. It enables web browsers to map the accessibility semantics in web content to platform-specific accessibility APIs. This enables web content to be interoperable with platform assistive technologies, similar to native platform applications, without requiring authors to include platform dependencies.

This specification is a modular extension of WAI-ARIA [WAI-ARIA] designed to support graphics. The goals of this specification include:

This specification defines the core roles that would be used in all structured graphics or diagrams. It establishes the default roles that can be used to describe graphical markup elements such as shapes and canvases. In combination with WAI-ARIA attributes to provide alternative text and to indicate relationships between elements, this provides a framework for annotating many figures and diagrams. Future work will expand on this framework to enable more detailed annotation of data-rich graphics such as charts or maps.

For a more detailed explanation of WAI-ARIA please refer to the WAI-ARIA Introduction and how it applies to Rich Internet Application Accessibility.

1.1 Target Audience§

This specification defines a module of WAI-ARIA for graphics, consisting of graphics-specific element roles . It impacts several audiences:

Each conformance requirement indicates the audience to which it applies.

1.2 User Agent Support§

This module follows the general User Agent support principles defined in WAI-ARIA [WAI-ARIA]. The roles defined here do not require any change in behavior by user agents other than in the information exposed to the accessibility API. However, the semantics defined here provide the ability for user agents to enhance the general user interface presented to readers. For example, a user agent may provide alternative keyboard navigation suitable to a graphical environment, or may allow users to extract a copy of a graphic from a larger document.

1.3 Co-Evolution of WAI-ARIA and Host Languages§

The WAI-ARIA Graphics module follows the model for co-evolution of WAI-ARIA and host languages defined in WAI-ARIA [WAI-ARIA]. It is intended to augment semantics in supporting languages like HTML [HTML5], SVG [SVG2] and EPUB, or to be used as an accessibility enhancement technology in other markup-based languages that do not explicitly include support for ARIA. WAI-ARIA roles clarify semantics to assistive technologies when authors create new types of objects, via style and script, or use markup languages which describe the visual appearance of a document rather than its meaning.

Although markup languages may provide some of these semantics natively, it is expected that there will be a persistent need for the semantics provided by the WAI-ARIA Graphics module. Some host languages exist to create semantics for features other than the user interface. For example, SVG expresses the semantics behind production of graphical objects, not of user interface components that those objects may represent. Host languages such as these might, by design, not provide native semantics that map to all of this specification's features. In these host languages, the WAI-ARIA Graphics module could be adopted as a long-term approach to add semantic information.

1.4 Authoring Practices§

1.4.1 Authoring Tools§

Many of the requirements in the definitions of the WAI-ARIA and Graphics WAI-ARIA roles, states and properties can be checked automatically during the development process, similar to other quality control processes used for validating code. To assist authors who are creating graphics, these tools can compare the semantic structure of Graphics WAI-ARIA roles from the DOM to that defined in this specification and notify the author of errors or simply create templates that enforce that structure.

1.4.2 Testing Practices and Tools§

The accessibility of interactive content cannot be confirmed by static checks alone. Developers of interactive content should test for device-independent access to widgets and applications, and should verify accessibility API access to all content and changes during user interaction.

1.5 Assistive Technologies§

Programmatic access to accessibility semantics is essential for assistive technologies. For more information, refer to the Assistive Technologies section in WAI-ARIA [WAI-ARIA].

For the graphics roles in particular, two categories of assistive technology are particularly relevant, but have different needs:

The role descriptions suggest which features of an element with that role are considered semantically important and should be conveyed to the reader whenever possible.

2. Conformance§

As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.

The key words MUST, SHOULD, and SHOULD NOT are to be interpreted as described in [RFC2119].

This specification indicates whether a section is normative or informative. Classifying a section as normative or informative applies to the entire section. A statement "This section is normative" or "This section is informative" applies to all sub-sections of that section.

Normative sections provide requirements that authors, user agents and assistive technologies MUST follow for an implementation to conform to this specification.

Informative sections provide information useful to understanding the specification. Such sections may contain examples of recommended practice, but it is not required to follow such recommendations in order to conform to this specification.

3. Important Terms§

This section is non-normative.

While some terms are defined in place, the following definitions are used throughout this document.

Accessibility API

Operating systems and other platforms provide a set of interfaces that expose information about objects and events to assistive technologies. Assistive technologies use these interfaces to get information about and interact with those widgets. Examples of accessibility APIs are Microsoft Active Accessibility [MSAA], Microsoft User Interface Automation [UI-AUTOMATION], MSAA with UIA Express [UIA-EXPRESS], the Mac OS X Accessibility Protocol [AXAPI], the Linux/Unix Accessibility Toolkit [ATK] and Assistive Technology Service Provider Interface [AT-SPI], and IAccessible2 [IAccessible2].

Assistive Technologies

Hardware and/or software that:

  • relies on services provided by a user agent to retrieve and render Web content
  • works with a user agent or web content itself through the use of APIs, and
  • provides services beyond those offered by the user agent to facilitate user interaction with web content by people with disabilities

This definition may differ from that used in other documents.

Examples of assistive technologies that are important in the context of this document include the following:

  • screen magnifiers, which are used to enlarge and improve the visual readability of rendered text and images;
  • screen readers, which are most-often used to convey information through synthesized speech or a refreshable Braille display;
  • text-to-speech software, which is used to convert text into synthetic speech;
  • speech recognition software, which is used to allow spoken control and dictation;
  • alternate input technologies (including head pointers, on-screen keyboards, single switches, and sip/puff devices), which are used to simulate the keyboard;
  • alternate pointing devices, which are used to simulate mouse pointing and clicking.
Attribute

In this specification, attribute is used as it is in markup languages. Attributes are structural features added to elements to provide information about the states and properties of the object represented by the element.

Class

A set of instance objects that share similar characteristics.

Element

In this specification, element is used as it is in markup languages. Elements are the structural elements in markup language that contains the data profile for objects.

Event

A programmatic message used to communicate discrete changes in the state of an object to other objects in a computational system. User input to a web page is commonly mediated through abstract events that describe the interaction and can provide notice of changes to the state of a document object. In some programming languages, events are more commonly known as notifications.

Informative

Content provided for information purposes and not required for conformance. Content required for conformance is referred to as normative.

Normative

Required for conformance. By contrast, content identified as informative or "non-normative" is not required for conformance.

Object

In the context of user interfaces, an item in the perceptual user experience, represented in markup languages by one or more elements, and rendered by user agents.

In the context of programming, the instantiation of one or more classes and interfaces which define the general characteristics of similar objects. An object in an accessibility API may represent one or more DOM objects. Accessibility APIs have defined interfaces that are distinct from DOM interfaces.
Ontology

A description of the characteristics of classes and how they relate to each other.

Property

Attributes that are essential to the nature of a given object, or that represent a data value associated with the object. A change of a property may significantly impact the meaning or presentation of an object. Certain properties (for example, aria-multiline) are less likely to change than states, but note that the frequency of change difference is not a rule. A few properties, such as aria-activedescendant, aria-valuenow, and aria-valuetext are expected to change often. See clarification of states versus properties.

Role

Main indicator of type. This semantic association allows tools to present and support interaction with the object in a manner that is consistent with user expectations about other objects of that type.

Semantics

The meaning of something as understood by a human, defined in a way that computers can process a representation of an object, such as elements and attributes, and reliably represent the object in a way that various humans will achieve a mutually consistent understanding of the object.

State

A state is a dynamic property expressing characteristics of an object that may change in response to user action or automated processes. States do not affect the essential nature of the object, but represent data associated with the object or user interaction possibilities. See clarification of states versus properties.

Taxonomy

A hierarchical definition of how the characteristics of various classes relate to each other, in which classes inherit the properties of superclasses in the hierarchy. A taxonomy can comprise part of the formal definition of an ontology.

User Agent

Any software that retrieves, renders and facilitates end user interaction with Web content. This definition may differ from that used in other documents.

Widget

Discrete user interface object with which the user can interact. Widgets range from simple objects that have one value or operation (e.g., check boxes and menu items), to complex objects that contain many managed sub-objects (e.g., trees and grids).

4. Graphics Roles§

This section defines additions to the WAI-ARIA role taxonomy and describes the characteristics and properties of all roles. See ARIA Roles for descriptions of the fields provided by this module.

Authors are given the ability to influence what is presented to assistive technologies and to influence navigation through the use of roles and properties. This includes the ability to mark elements as having no semantic importance. With graphics, there are many cases where presenting and navigating every element will make the graphic harder to understand and use.

Authors may mark elements for exclusion from the semantic representation of the document (the accessibility tree) by assigning the role none or presentation. The element with this role should be treated transparently by assistive technologies, as if its children or text content were directly contained by its parent element. In addition, certain roles, such as img or graphics-symbol, when assigned to a parent element, will cause all child DOM structure to be omitted from the accessibility tree. This is indicated by the "Children Presentational" value in the role characteristics table. Finally, the native semantics of the graphics language may also default to ignoring DOM structure that does not have semantic data attached; for SVG, this is defined in the SVG Accessibility API Mappings specification [SVG-AAM].

In all cases, to be considered presentational, an element must not be interactive and must not be assigned any accessible properties or alternative text. A role of none or presentation will be ignored for interactive elements or those with WAI-ARIA states and properties.

4.1 Definition of Roles§

Below is an alphabetical list of the WAI-ARIA roles defined in this specification. They would normally be used in combination with other roles defined in WAI-ARIA to annotate graphics within documents and rich internet applications [WAI-ARIA].

graphics-document
A type of document in which the visual appearance or layout of content conveys meaning.
graphics-object
A section of a graphics-document that represents a distinct object or sub-component with semantic meaning. A graphical object may itself have nested sub-components.
graphics-symbol
A graphical object used to convey a simple meaning or category, where the meaning is more important than the particular visual appearance. It may be a component of a larger structured graphic such as a chart or map. The symbol itself is an atomic object; children are presentational.

graphics-document (role)§

A type of document in which the visual appearance or layout of content conveys meaning.

Similar to other document types, the graphics-document role applies to the root element of a region of the page containing related information, where the user's primary interaction mode is expected to be browsing the document rather than controlling an application. The element with this role may be the root element of the document file, or of a nested structure within it.

The graphics-document may be distinguished from similar roles as follows:

  • Relative to other documents, a graphics-document is distinguished by the semantic importance of its visual (usually two-dimensional) representation. User agents and assistive technologies SHOULD take this into consideration when supporting navigation of the graphic. Accessibility technologies that re-format or re-style a document SHOULD NOT alter the layout of a graphics-document except in ways that are consistent with the semantic roles and relationships of its content.

  • Relative to an img, a graphics-document is distinguished by the structured nature of its content. Its child elements may have semantic meaning, and may include links or other interactive widgets.

  • Relative to a graphics-object, a graphics-document is self-contained. Its meaning persists when separated from surrounding content. The element with the graphics-document role defines the scope and context for interpretation of the child content.

In general, authors SHOULD use the graphics-document role for structured graphics such as charts, maps, diagrams, technical drawing, blue prints and instructional graphics. However, if a single large graphic has discrete regions that may be safely re-arranged without sacrificing meaning, each of those regions SHOULD be a distinct graphics-document. An alternative role (such as figure) may be used to group them together. One graphics-document may also be nested inside another, for example a bar chart that is embedded in a map or a matrix of chart panels should have a role of graphics-document. The nested document provides encapsulation; navigation between components of the inner and outer graphics should be explicit.

Note

To support user agents and assistive technologies based on the ARIA 1.0 specification, authors may wish to include the document role as a fallback value, in the form role="graphics-document document".

Future specifications may define more specific roles for particular types of graphical documents with special semantic structures. Those more specific roles would be subclasses of graphics-document.

Example 1
<!-- An SVG diagram of an electrical circuit -->
<svg xmlns="http://www.w3.org/2000/svg" 
     width="400" height="200" viewBox="0 0 200 100"
     role="graphics-document document" >
     <title>A simple circuit</title>
     <desc>A circuit with one source, one switch, and one load</desc>
     <style type="text/css">
        /* omitted */
     </style>
     <g id="battery-1" role="graphics-symbol img" 
        aria-roledescription="source" 
        aria-label="battery"
        aria-flowto="switch-1" 
        transform="translate(20,50)" >
        <path d="M-15,-5 h30 M-5,5 h10" />
     </g>
     <path class="wire" d="M20,45 V20 H90"/>
     <g id="switch-1" role="graphics-symbol img" 
        aria-roledescription="switch" 
        aria-label="single-pole switch"
        aria-flowto="lightbulb-1" >
        <path d="M90,20 L105,30" />
        <circle class="connection" cx="90" cy="20" r="2" />
        <circle class="connection" cx="110" cy="20" r="2" />
     </g>
     <!-- more wires and a light bulb --> 
</svg>

Characteristics:
Characteristic Value
Superclass Role: document
Related Concepts:
Inherited States and Properties:
Name From: author
Accessible Name Required: True
Children Presentational: False

graphics-object (role)§

A section of a graphics-document that represents a distinct object or sub-component with semantic meaning. A graphical object may itself have nested sub-components.

Container elements that instead represent a collection of disconnected objects should instead be given the group or list roles. Grouping elements that do not have semantic meaning and do not alter the semantic context provided by an ancestor SHOULD NOT be given a role, which may be explicitly indicated with the role none or presentation.

Unlike a graphics-document, a graphics-object need not be self-contained, and it does not establish a new context for navigation. However, user agents and assistive technologies SHOULD provide a way for users, particularly non-visual users, to navigate the nested structure of objects in a hierarchical manner, similar to nested lists.

Note

To support user agents and assistive technologies based on the ARIA 1.0 specification, authors may wish to include the group role as a fallback value, in the form role="graphics-object group".

The code that follows is a portion of the markup for a structured graphic. It includes SVG g grouping elements with various roles:

  • graphics-object for distinct objects, such as the house, its door, or roof.
  • group to group together the windows or the trees (multiple distinct objects) with a single label or description.
  • img for the background which is described as a whole.
  • none for elements that apply styles or transformations without having any semantic meaning.

Where a graphical object has multiple sub-components, the group role is provided as an explicit fallback.

<svg xmlns="http://www.w3.org/2000/svg"
     width="600" height="400" viewBox="0 0 600 400"
     role="graphics-document document" xml:lang="en">
    <title>Home</title>
    <g role="img" aria-label="background">
        <desc>Blue sky, sunshine, and green grass</desc>
        <!-- The multiple parts of the background form a single image
             conveyed by that one description. -->
        <rect fill="lightSkyBlue" height="100%" width="100%" />
        <circle fill="yellow" stroke="gold" stroke-width="4"
                cx="0" cy="0" r="50" />
        <path fill="none" stroke="gold" stroke-width="3"
              d="..." />
        <rect fill="#6a2" y="300" width="100%" height="100" />
    </g>
    <g role="graphics-object group"
       aria-labelledby="house-label"
       transform="translate(100,325)">
        <desc>A two-storey brick house, drawn with basic shapes.
        </desc>
        <!-- The house has a number of details worth calling out,
             so it is a graphical object -->

        <rect fill="firebrick" stroke="darkRed"
              width="300" height="200" y="-200"
              role="none" /><!-- the walls of the house are 
                already described thoroughly,
                so no role is required -->

        <g role="graphics-object" aria-label="door"
           transform="translate(30,-90)">
            <desc>The brown door on the left side of the building
                has a window and a round doorknob</desc>
            <!-- The graphical object role allows for further
                 nested sub-components.
                 However, based on the default SVG API mappings,
                 these shapes, which have neither labels nor descriptions,
                 will be treated as presentation. -->
            <rect fill="darkKhaki" stroke="#632"
                  width="50" height="90"/>
            <rect fill="lightSteelBlue" stroke="#632" stroke-width="4" 
                  x="5" y="5" width="40" height="30" />
            <circle fill="gray" stroke="#444" stroke-width="0.7"
                    cx="10" cy="50" r="4" />
        </g>

        <g role="group" aria-label="windows"
           fill="lightSteelBlue" stroke="#632" stroke-width="6">
            <!-- The windows are distinct objects, 
                 grouped together with a common label -->
            <g role="none" transform="translate(0,-85)">
                <rect aria-label="first-floor window"
                      x="100" width="25" height="45">
                    <desc>A small window beside the door</desc>
                </rect>
                <path aria-label="first-floor living-room window"
                      d="M180,0h100v60h-100v-60z
                         m30,0v60 m40,0v-60">
                    <desc>A large three-pane window fills
                    the rest of the first floor</desc>
                </path>
            </g>
            <g role="none" transform="translate(0,-180)">
                <!-- more windows on the second floor -->
            </g>
        </g>
        <!-- more markup for the roof and chimney -->

        <text id="house-label"
              font-family="cursive" font-size="36px" 
              x="70" y="50">My House</text>
    </g>
    <!-- more markup for the trees -->
</svg>
Characteristics:
Characteristic Value
Superclass Role: structure
Subclass Roles:
Related Concepts:
Inherited States and Properties:
Name From:
  • author
  • contents
Accessible Name Required: False
Children Presentational: False

graphics-symbol (role)§

A graphical object used to convey a simple meaning or category, where the meaning is more important than the particular visual appearance. It may be a component of a larger structured graphic such as a chart or map. The symbol itself is an atomic object; children are presentational.

When used as part of a structured symbolic language, the aria-roledescription property (introduced in ARIA 1.1 [WAI-ARIA]) can be used to name the symbol type separately from the name and description for the particular instance of the symbol.

Note

To support user agents and assistive technologies based on the ARIA 1.0 specification, authors may wish to include the img role as a fallback value, in the form role="graphics-symbol img", if that is not already the default semantic role for the element.

Example 2
<!-- Within an HTML document listing a restaurant menu -->
<h2>Appetizers</h2>
<ul>
    <li> Spinach Salad with Strawberry & Almonds
        <img role="graphics-symbol" title="Vegetarian" src="../assets/leaf.svg" />
        <img role="graphics-symbol" title="Contains Nuts" src="../assets/peanut.svg" />
    </li>
    <li> Chicken Satay with Peanut Sauce
        <img role="graphics-symbol" title="Contains Nuts" src="../assets/peanut.svg" />
    </li>
    <!-- … -->
</ul>
Example 3
<!-- Within an SVG diagram of an electrical circuit -->
<g id="lightbulb-1" role="graphics-symbol img" 
   aria-roledescription="load" 
   aria-label="lightbulb"
   aria-describedby="lightbulb-1-label"
   aria-flowto="battery-1" 
   transform="translate(180,50)">
    <text id="lightbulb-1-label"
        x="-15" dy="0.5ex" text-anchor="end" >10W</text>
    <circle r="10" />
    <path d="M0,-10 C0,8 5,8 5,0 C5,-8 0,-8 0,10" />
</g>

Example 4
<!-- Within an architectural blueprint-style SVG diagram -->
<g role="graphics-symbol img">
    <title>Door</title>
    <desc>on West side of South wall</desc>
    <line stroke-width="8" stroke="white" 
          x1="50" y1="275" x2="150" y2="275"/>
    <line stroke-width="4" stroke="#444" 
          x1="50" y1="275" x2="125" y2="225"/>        
</g>
<!-- … -->
<use xlink:href="#outlet" role="graphics-symbol img" 
     x="5" y="130" width="40" height="40">
    <title>Electrical outlet</title>
    <desc>at center of West wall</desc>
</use>

Characteristics:
Characteristic Value
Superclass Role: graphics-object
Related Concepts:
Inherited States and Properties:
Name From: author
Accessible Name Required: True
Children Presentational: True

4.2 Other Roles for Graphics§

The following core ARIA roles, defined in ARIA 1.1 [WAI-ARIA], are also relevant for annotating graphics:

The following examples demonstrate appropriate use of img, figure, and graphics-document in a document.

Within an HTML 5 document, an inline SVG may sometimes represent an atomic img. If the graphics form part of the natural reading flow of the text, then this role is sufficient, as in the first example:

Example 5
<p>A repeating SVG gradient is defined using the
    <code>spreadMethod</code> attribute.  
    A value of <code>repeat</code> causes the color stops
    to repeat in the same order, from beginning to end:</p>
<svg class="inline-example" role="img">
    <title>A repeating linear gradient</title>
    <desc>The gradient starts dark, slowly shifting to light, 
        then quickly dark again.  This pattern repeats four
        times left to right, each time brightening across a large
        region and then getting dark within a short space.
    </desc>
    <linearGradient id="repeat" x2="25%" spreadMethod="repeat">
        <stop offset="0"     stop-color="black" />
        <stop offset="0.8" stop-color="white" />
        <stop offset="1"     stop-color="black" />
    </linearGradient>
    <rect width="100%" height="100%" fill="url(#repeat)" />
</svg>

The following example provides the same content, but now structured as a figure that may be re-positioned separately from the flow of paragraph text.

Example 6
<figure id="fig1" role="figure region">
    <svg id="fig1A" class="nested-figure" role="figure"
         aria-labelledby="fig1-caption, fig1A-caption">
        <!-- markup omitted-->
    </svg>
    <svg id="fig1B" class="nested-figure" role="figure"
         aria-labelledby="fig1-caption, fig1B-caption">
        <linearGradient id="reflect" spreadMethod="reflect"
                        xlink:href="#repeat" />
        <text id="fig1B-caption" class="caption" dy="1em"
              >b) spreadMethod="reflect"</text>
        <rect role="img"
              y="25%" width="100%" height="75%" fill="url(#reflect)" >
            <title>A reflecting linear gradient</title>
            <desc>The gradient again starts dark, slowly shifting to light, 
              then quickly dark again.  However, the next repeat shifts
              quickly to the light, then slowly back dark.  
              The original pattern is then repeated, followed by the reflected
              version again.
            </desc>
        </rect>
    </svg>
    <figcaption id="fig1-caption"
                >Figure 1: Repeating SVG gradients</figcaption>
</figure>

Finally, the last version uses a graphics-document to include complex annotations on the graphic, which is still contained within a figure element. The two sections of the graphic are graphics-object elements, while the annotations have individual labels and descriptions.

Example 7
<figure id="fig1" role="figure region">
    <svg role="graphics-document">
        <title>Repeating versus reflecting linear gradients</title>
        <desc>
            The graphic shows two gradient patterns,
            annotated with text labels and arrows.
            Both gradients use the same series of color stops,
            starting dark, slowly shifting to light, 
            then quickly dark again.
            This cycle covers one-quarter of the width of the graphic,
            starting on the left.
            The two gradients differ in their repeat cycles.
        </desc>
        <defs>
            <!-- markup omitted -->
        </defs>
        <g role="graphics-object" aria-labelledby="repeat-label">
            <!-- markup omitted -->
        </g>            
        <g role="graphics-object" aria-labelledby="reflect-label">
            <desc>
                The gradient stretches across the bottom half of 
                the graphic.
                Each cycle of the gradient alternates direction,
                left-to-right then right-to-left,
                as do the arrows that emphasize the pattern.
            </desc>
            <rect y="50%" width="100%" height="50%" fill="url(#reflect)" />
            </rect>
            <use y="70%" xlink:href="#gradient-vector" >
                <title>1st cycle</title>
                <desc>left-to-right arrow, starting from x="0"</desc>
            </use>
            <use y="70%" x="-50%" transform="scale(-1,1)"
                 xlink:href="#gradient-vector" >
                <title>2nd cycle, reflected</title>
                <desc>right-to-left arrow, ending at x="25%"</desc>
            </use>
            <use y="70%" x="50%" xlink:href="#gradient-vector" >
                <title>3rd cycle</title>
                <desc>left-to-right arrow, starting from x="50%"</desc>
            </use>
            <use y="70%" x="-100%" transform="scale(-1,1)"
                 xlink:href="#gradient-vector" >
                <title>4th cycle, reflected</title>
                <desc>right-to-left arrow, ending at x="75%"</desc>
            </use>
            <text id="reflect-label" class="overlay-text" 
                  aria-label="spreadMethod='reflect'"
                  dy="-0.2em" dx="-0.2em" x="100%" y="100%"
                  >reflect</text>
        </g>
    </svg>
    <figcaption>Figure 1: spreadMethod options for
        repeating SVG gradients</figcaption>
</figure>
Editor's Note

Should we expand on the following example to demonstrate how canvas hit regions create a graphical document?

Example 8
<!-- Within the fallback DOM dynamically constructed
     for an HTML 5 canvas game,
     elements may represent the different images
     that create the composite graphic -->
<canvas role="graphics-document">
    <p id="scene-desc" role="img" 
       aria-label="The Dungeon"
       aria-describedby="scene-desc">
       The door opens into a long hallway.
       Every few steps on either side are barred doors.
       Moisture drips from the stone walls.
    </p>
    <p id="grue-1" role="img"
       aria-label="Grue"
       aria-describedby="grue-1">
       An amorphous and poorly defined, but unmistakably sinister,
       creature blocks the passage.
   </p>
   <!-- more DOM elements representing game controls -->
</canvas>

5. States and Properties§

WAI-ARIA provides a collection of accessibility state and properties which are used to support platform accessibility APIs on various operating system platforms. Assistive technologies may access this information through an exposed user agent DOM or through a mapping to the platform accessibility API. When combined with roles, the user agent can supply the assistive technologies with user interface information to convey to the user at any time. Changes in states or properties will result in a notification to assistive technologies, which could alert the user that a change has occurred.

A. Schemata§

This section is non-normative.

WAI-ARIA attributes are natively incorporated into HTML since HTML 5. Official support for WAI-ARIA in HTML is provided in that and subsequent HTML specifications. WAI-ARIA attributes are natively incorporated into SVG by the SVG 2 specification.

Editor's Note

Validation support for the roles defined in this module will be added once the specification reaches recommendation.

For information on incorporating WAI-ARIA into other grammars, refer to Appendix A of the ARIA 1.1 specification [WAI-ARIA].

Editor's Note

Review whether any additional schemata are necessary for this module.

B. Change Log§

A detailed history of changes committed is available from the github repository for this document. When drafts of this document begin to stabilise, human-readable change logs will be incorporated.

C. WAI-ARIA Role, State, and Property Quick Reference§

This section is non-normative.

The following table provides a quick reference to the supported states and properties for all WAI-ARIA roles that may be used in markup.

In addition to the states and properties shown in the table, the following global states and properties are supported on all roles.

Placeholder for global states and properties

Placeholder for quick reference table

D. Acknowledgments§

This section is non-normative.

The following people contributed to the development of this document.

D.1 Participants active in the SVG accessibility task force at the time of publication§

D.2 Participants active in the PFWG at the time of publication§

D.3 Enabling funders§

This publication has been funded in part with U.S. Federal funds from the Department of Education, National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR), initially under contract number ED-OSE-10-C-0067 and currently under contract number HHSP23301500054C. The content of this publication does not necessarily reflect the views or policies of the U.S. Department of Education, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.

E. References§

E.1 Normative references§

[RFC2119]
S. Bradner. IETF. Key words for use in RFCs to Indicate Requirement Levels. March 1997. Best Current Practice. URL: https://tools.ietf.org/html/rfc2119
[WAI-ARIA]
James Craig; Michael Cooper; Shane McCarron et al. W3C. Accessible Rich Internet Applications (WAI-ARIA) 1.1. W3C Working Draft. URL: http://www.w3.org/TR/wai-aria-1.1/

E.2 Informative references§

[AT-SPI]
The GNOME Project. Assistive Technology Service Provider Interface. URL: https://developer.gnome.org/libatspi/stable/
[ATK]
The GNOME Project. ATK - Accessibility Toolkit. URL: https://developer.gnome.org/atk/stable/
[AXAPI]
Apple Corporation. The Mac OS X Accessibility Protocol Mac OS 10.10. URL: https://developer.apple.com/library/mac/documentation/Cocoa/Reference/ApplicationKit/Protocols/NSAccessibility_Protocol/index.html
[HTML5]
Ian Hickson; Robin Berjon; Steve Faulkner; Travis Leithead; Erika Doyle Navara; Edward O'Connor; Silvia Pfeiffer. W3C. HTML5. 28 October 2014. W3C Recommendation. URL: https://www.w3.org/TR/html5/
[IAccessible2]
Linux Foundation. IAccessible2. URL: http://www.linuxfoundation.org/collaborate/workgroups/accessibility/iaccessible2
[MSAA]
Microsoft Corporation. Microsoft Active Accessibility (MSAA) 2.0. URL: https://msdn.microsoft.com/en-us/library/ms697707.aspx
[SVG-AAM]
Amelia Bellamy-Royds; Richard Schwerdtfeger et al. W3C. SVG2 Accessibility API Mappings 1.0. W3C Working Draft. URL: http://www.w3.org/TR/svg-aam-1.0/
[SVG2]
Nikos Andronikos; Rossen Atanassov; Tavmjong Bah; Amelia Bellamy-Royds; Brian Birtles; Cyril Concolato; Erik Dahlström; Chris Lilley; Cameron McCormack; Doug Schepers; Dirk Schulze; Richard Schwerdtfeger; Satoru Takagi; Jonathan Watt et al. W3C. Scalable Vector Graphics (SVG) 2. W3C Working Draft. URL: http://www.w3.org/TR/2015/WD-SVG2-20150915/
[UI-AUTOMATION]
Microsoft Corporation. UI Automation. URL: https://msdn.microsoft.com/en-us/library/ee684009%28v=vs.85%29.aspx
[UIA-EXPRESS]
Microsoft Corporation. The IAccessibleEx Interface. URL: https://msdn.microsoft.com/en-us/library/windows/desktop/dd561898%28v=vs.85%29.aspx
[WAI-ARIA-IMPLEMENTATION]
Joseph Scheuhammer; Michael Cooper. W3C. WAI-ARIA 1.0 User Agent Implementation Guide. 20 March 2014. W3C Recommendation. URL: https://www.w3.org/TR/wai-aria-implementation/
[WAI-ARIA-PRACTICES]
Joseph Scheuhammer; Michael Cooper. W3C. WAI-ARIA 1.0 Authoring Practices. 14 July 2016. W3C Working Draft. URL: https://www.w3.org/TR/wai-aria-practices/
[WCAG20]
Ben Caldwell; Michael Cooper; Loretta Guarino Reid; Gregg Vanderheiden et al. W3C. Web Content Accessibility Guidelines (WCAG) 2.0. 11 December 2008. W3C Recommendation. URL: https://www.w3.org/TR/WCAG20/