VRFrameData: timestamp property
Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
The timestamp
read-only property of the 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 It has been superseded by the WebXR Device API.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 VRDisplay.getFrameData()
is invoked for a given VRDisplay
.
Value
A 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This property was part of the old WebVR API that has been superseded by the WebXR Device API.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 [1].
Browser compatibility
BCD tables only load in the browser
See also
- WebVR API homepage
- https://mixedreality.mozilla.org/ — demos, downloads, and other resources from the Mozilla VR team.