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VRFrameData: timestamp property

files/en-us/web/api/vrframedata/timestamp/index.md

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{{APIRef("WebVR API")}}{{Deprecated_Header}}{{Non-standard_Header}}

The timestamp read-only property of the {{domxref("VRFrameData")}} interface returns a constantly increasing timestamp value representing the time a frame update occurred.

[!NOTE] This property was part of the old WebVR API. It has been superseded by the WebXR Device API.

Timestamps are useful for determining if position state data has been updated from the hardware. Since values are monotonically increasing, they can be compared to determine the ordering of updates — newer values will always be greater than or equal to older values.

The timestamp starts at 0 the first time {{domxref("VRDisplay.getFrameData()")}} is invoked for a given {{domxref("VRDisplay")}}.

Value

A {{domxref("DOMHighResTimeStamp")}} object.

Examples

js
const frameData = new VRFrameData();
let vrDisplay;

navigator.getVRDisplays().then((displays) => {
  vrDisplay = displays[0];
  console.log("Display found");
  // Starting the presentation when the button is clicked: It can only be called in response to a user gesture
  btn.addEventListener("click", () => {
    vrDisplay.requestPresent([{ source: canvas }]).then(() => {
      drawVRScene();
    });
  });
});

// WebVR: Draw the scene for the WebVR display.
function drawVRScene() {
  // WebVR: Request the next frame of the animation
  vrSceneFrame = vrDisplay.requestAnimationFrame(drawVRScene);

  // Populate frameData with the data of the next frame to display
  vrDisplay.getFrameData(frameData);

  // grab the current timestamp on each run of the rendering loop
  // and do something with it
  frameData.timestamp;

  // …

  // WebVR: Indicates that we are ready to present the rendered frame to the VR display
  vrDisplay.submitFrame();
}

Specifications

This property was part of the old WebVR API that has been superseded by the WebXR Device API. It is no longer on track to becoming a standard.

Until all browsers have implemented the new WebXR APIs, it is recommended to rely on frameworks, like A-Frame, Babylon.js, or Three.js, or a polyfill, to develop WebXR applications that will work across all browsers. Read Meta's Porting from WebVR to WebXR guide for more information.

Browser compatibility

{{Compat}}

See also