ISSUE: <a href="https://github.com/immersive-web/webxr/issues/550">GitHub #550</a> - Additional restrictions, still under discussion, will be applied to the formatting of the {{XRInputSource/gamepad}}'s {{Gamepad/id}} attribute. Until those restrictions have been identified, all {{XRInputSource/gamepad}} {{Gamepad/id}}'s should default to <code>"unknown"</code>.

"xr-standard" Gamepad Mapping {#xr-standard-gamepad-mapping}

-----------------------------

The <dfn enum-value for="GamepadMappingType">xr-standard</dfn> mapping indicates that the layout of the buttons and axes of the {{XRInputSource/gamepad}} corresponds as closely as possible to the tables below.

<thead>

<tr>

<th>Buttons</th>

<th>Required</th>

</tr>

</thead>

</tr>

<tr>

<td>buttons[1]</td>

</tr>

<tr>

<td>buttons[2]</td>

<td>No</td>

</tr>

<tr>

<td>buttons[3]</td>

<td>No</td>

</tr>

</tbody>

<thead>

<tr>

<th>Axes</th>

<th>Required</th>

</tr>

</thead>

<tbody>

<tr>

<td>axes[0]</td>

</tr>

<tr>

<td>axes[1]</td>

</tr>

<tr>

<td>axes[2]</td>

<td>No</td>

</tr>

<tr>

<td>axes[3]</td>

<td>No</td>

</tr>

</tbody>

Devices that lack one of the optional inputs listed in the tables above MUST preserve their place in the {{Gamepad/buttons}} or {{Gamepad/axes}} array, reporting a <dfn>placeholder button</dfn> or <dfn>placeholder axis</dfn>, respectively. A [=placeholder button=] MUST report <code>0</code> for {{GamepadButton/value}}, <code>false</code> for {{GamepadButton/pressed}}, and <code>false</code> for {{GamepadButton/touched}}. A [=placeholder axis=] MUST report <code>0</code>. [=Placeholder buttons=] and [=placeholder axis|axes=] MUST be omitted if they are the last element in the array or all following elements are also [=placeholder buttons=] or [=placeholder axis|axes=].

Layers {#layers}

A user agent MUST dispatch a <dfn event for="XRReferenceSpace">reset</dfn> event on an {{XRReferenceSpace}} when discontinuities of the [=native origin=] or [=effective origin=] occur, i.e. there are significant changes in the origin’s position or orientation relative to the user’s environment. (For example: After user recalibration of their XR device or if the XR device automatically shifts its origin after losing and regaining tracking.) A {{reset}} event MUST also be dispatched when the {{boundsGeometry}} changes for an {{XRBoundedReferenceSpace}}. A {{reset}} event MUST NOT be dispatched if the [=viewer=]'s pose experiences discontinuities but the {{XRReferenceSpace}}'s origin physical mapping remains stable, such as when the [=viewer=] momentarily loses and regains tracking within the same tracking area. A {{reset}} event also MUST NOT be dispatched as an {{unbounded}} reference space makes small adjustments to its [=native origin=] over time to maintain space stability near the user, if a significant discontinuity has not occurred. The event MUST be of type {{XRReferenceSpaceEvent}}, and MUST be dispatched prior to the execution of any [=XR animation frame=]s that make use of the new origin.

Security, Privacy, and Comfort Considerations {#security}

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