1. Set the [=XR compatible=] boolean of all {{WebGLRenderingContextBase}} instances to <code>false</code>.

To <dfn>populate the pose</dfn> of an {{XRSpace}} |space| in an {{XRSpace}} |baseSpace| at the time represented by an {{XRFrame}} |frame| into an {{XRPose}} |pose|, the user agent MUST run the following steps:

1. If |frame|'s [=active=] boolean is <code>false</code>, throw an {{InvalidStateError}} and abort these steps.

1. Query the [=/XR device=]'s tracking system for |space|'s pose relative to |baseSpace| at the time represented by |frame|, then perform the following steps:

<dl class="switch">

<dt> If the tracking system provides a [=6DoF=] pose whose position is actively tracked or statically known for |space|'s pose relative to |baseSpace|:

<dd> Set |transform|'s {{XRRigidTransform/orientation}} to the orientation of |space|'s [=effective origin=] in |baseSpace|'s [=coordinate system=].

<dd> Set |transform|'s {{XRRigidTransform/position}} to the position of |space|'s [=effective origin=] in |baseSpace|'s [=coordinate system=].

<dd> Set |pose|'s {{XRPose/emulatedPosition}} to <code>false</code>.

<dt> Else if the tracking system provides a [=3DoF=] pose or a [=6DoF=] pose whose position is neither actively tracked nor statically known for |space|'s pose relative to |baseSpace|:

<dd> Set |transform|'s {{XRRigidTransform/orientation}} to the orientation of |space|'s [=effective origin=] in |baseSpace|'s [=coordinate system=].

<dd> Set |transform|'s {{XRRigidTransform/position}} to the tracking system's best estimate of the position of |space|'s [=effective origin=] in |baseSpace|'s [=coordinate system=]. This MAY include a computed offset such as a neck or arm model. If a position estimate is not available, the last known position MUST be used.

<dd> Set |pose|'s {{XRPose/emulatedPosition}} to <code>true</code>.

<dt> Else if |space|'s pose relative to |baseSpace| has been determined in the past:

<dd> Set |transform|'s {{XRRigidTransform/position}} to the last known position of |space|'s [=effective origin=] in |baseSpace|'s [=coordinate system=].

<dd> Set |transform|'s {{XRRigidTransform/orientation}} to the last known orientation of |space|'s [=effective origin=] in |baseSpace|'s [=coordinate system=].

<dd> Set |pose|'s {{XRPose/emulatedPosition}} boolean to <code>true</code>.

<dt> Else if |space|'s pose relative to |baseSpace| has never been determined:

<dd> Set |pose| to <code>null</code>.

</dl>

NOTE: The {{XRPose}}'s {{XRPose/emulatedPosition}} boolean does not indicate whether |baseSpace|'s position is emulated or not, only whether evaluating |space|'s position relative to |baseSpace| relies on emulation. For example, a controller with [=3DoF=] tracking would report poses with an {{XRPose/emulatedPosition}} of <code>true</code> when its {{targetRaySpace}} or {{gripSpace}} are queried against an {{XRReferenceSpace}}, but would report an {{XRPose/emulatedPosition}} of <code>false</code> if the pose of the {{targetRaySpace}} was queried in {{gripSpace}}, because the relationship between those two spaces should be known exactly.

- Passing a type of <dfn enum-value for="XRReferenceSpaceType">local-floor</dfn> creates an {{XRReferenceSpace}} instance. It represents a tracking space with a [=native origin=] at the floor in a safe position for the user to stand. The <code>y</code> axis equals <code>0</code> at floor level, with the <code>x</code> and <code>z</code> position and orientation initialized based on the conventions of the underlying platform. If the floor level isn't known it MUST be estimated. When using this reference space the user is not expected to move beyond their initial position much, if at all, and tracking is optimized for that purpose. For devices with [=6DoF=] tracking, {{local-floor}} reference spaces should emphasize keeping the origin stable relative to the user's environment.

The origin of an {{XRBoundedReferenceSpace}} MUST be positioned at the floor, such that the <code>y</code> axis equals <code>0</code> at floor level. The <code>x</code> and <code>z</code> position and orientation are initialized based on the conventions of the underlying platform, typically expected to be near the center of the room facing in a logical forward direction.

NOTE: The {{XRView/transform}} can be used to position camera objects in many rendering libraries. If a more traditional view matrix is needed by the application one can be retrieved by calling <code>view.transform.inverse.matrix</code>.

The <dfn attribute for="XRPose">emulatedPosition</dfn> attribute is <code>false</code> when the {{XRPose/transform}} represents an actively tracked [=6DoF=] pose based on sensor readings, or <code>true</code> if its {{XRRigidTransform/position}} value includes a computed offset, such as that provided by a neck or arm model.

NOTE: This diagram demonstrates how two potential controllers would be exposed with the {{GamepadMappingType/xr-standard}} mapping. <img src="images/xr-standard-mapping.svg" alt="Simple 'xr-standard' controller and Advanced 'xr-standard' controller">

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.

NOTE: Jumps in [=viewer=] position can be handled by the application by observing the {{XRPose/emulatedPosition}} boolean. If a jump in [=viewer=] position coincides with {{XRPose/emulatedPosition}} switching from <code>true</code> to <code>false</code>, it indicates that the [=viewer=] has regained tracking and their new position represents a correction from the previously emulated values. For experiences without a "teleportation" mechanic, where the [=viewer=] can move through the virtual world without moving physically, this is generally the application's desired behavior. However, if an experience does provide a "teleportation" mechanic, it may be needlessly jarring to jump the [=viewer=]'s position back after tracking recovery. Instead, when such an application recovers tracking, it can simply resume the experience from the [=viewer=]'s current position in the virtual world by absorbing that sudden jump in position into its teleportation offset. To do so, the developer calls {{getOffsetReferenceSpace()}} to create a replacement reference space with its |originOffset| adjusted by the amount that the [=viewer=]'s position jumped since the previous frame.