PointerEvent: altitude angle property

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The altitude angle read-only property of the PointerEvent interface represents the angle between a transducer (a pointer or stylus) axis and the X-Y plane of a device screen. The altitude angle describes whether the transducer is perpendicular to the screen, parallel, or at some angle in between.

Depending on the specific hardware and platform, user agents will likely only receive one set of values for the transducer orientation relative to the screen plane — either tiltX and tiltY or altitudeAngle and azimuthAngle.

The azimuth angle of a pointer compared to the altitude angle

For an additional illustration of this property, see Figure 4 in the specification.

Value

An angle in radians between 0 and π/2 where 0 is parallel to the device surface (X-Y plane), and π/2 is perpendicular to the surface. Defaults to π/2 (perpendicular to the surface) which differs from the altitudeAngle in touch events which defaults to 0 (parallel to the surface). For hardware and platforms that do not report tilt or angle, the value is π/2.

Example

js

someElement.addEventListener(
  "pointerdown",
  (event) => {
    process_angles(event.altitudeAngle, event.azimuthAngle);
  },
  false
);

Specifications

Specification
Pointer Events
# dom-pointerevent-altitudeangle

Browser compatibility

BCD tables only load in the browser

See also