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web api interface

RelativeOrientationSensor

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Secure context

The RelativeOrientationSensor interface of the Sensor APIs describes the device’s physical orientation without regard to the Earth’s reference coordinate system.

To use this sensor, the user must grant permission to the 'accelerometer', and 'gyroscope' device sensors through the Permissions API. In addition, this feature may be blocked by a Permissions Policy set on your server.

Constructor

Instance properties

No specific properties; inherits properties from its ancestors OrientationSensor and Sensor.

Instance methods

No specific methods; inherits methods from its ancestors OrientationSensor and Sensor.

Events

No specific events; inherits events from its ancestor, Sensor.

Examples

Basic Example

The following example, which is loosely based on Intel’s Orientation Phone demo, instantiates a RelativeOrientationSensor with a frequency of 60 times a second.

[!NOTE] The Intel demo this is based on uses the AbsoluteOrientationSensor. On each reading it uses quaternion to rotate a visual model of a phone.

const options = { frequency: 60, referenceFrame: "device" };
const sensor = new RelativeOrientationSensor(options);

sensor.addEventListener("reading", () => {
  // model is a Three.js object instantiated elsewhere.
  model.quaternion.fromArray(sensor.quaternion).inverse();
});
sensor.addEventListener("error", (error) => {
  if (event.error.name === "NotReadableError") {
    console.log("Sensor is not available.");
  }
});
sensor.start();

Permissions Example

Using orientation sensors requires requesting permissions for multiple device sensors. Because the Permissions interface uses promises, a good way to request permissions is to use all.

const sensor = new RelativeOrientationSensor();
Promise.all([
  navigator.permissions.query({ name: "accelerometer" }),
  navigator.permissions.query({ name: "gyroscope" }),
]).then((results) => {
  if (results.every((result) => result.state === "granted")) {
    sensor.start();
    // …
  } else {
    console.log("No permissions to use RelativeOrientationSensor.");
  }
});

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.