VRDisplay.requestAnimationFrame()

Experimental: 这是一个实验中的功能
此功能某些浏览器尚在开发中，请参考浏览器兼容性表格以得到在不同浏览器中适合使用的前缀。由于该功能对应的标准文档可能被重新修订，所以在未来版本的浏览器中该功能的语法和行为可能随之改变。

The requestAnimationFrame() method of the VRDisplay interface is a special implementation of Window.requestAnimationFrame containing a callback function that will be called every time a new frame of the VRDisplay presentation is rendered:

When the VRDisplay is not presenting a scene, this is functionally equivalent to Window.requestAnimationFrame.
When the VRDisplay is presenting, the callback is called at the native refresh rate of the VRDisplay.

Syntax

var handle = vrDisplayInstance.requestAnimationFrame(callback);

Parameters

callback: A callback function that will be called every time a new frame of the VRDisplay presentation is rendered.

Return value

A long representing the handle of the requestAnimationFrame() call. This can then be passed to a VRDisplay.cancelAnimationFrame() (en-US) call to unregister the callback.

Examples

TBD.

Specifications

该 API 在旧的 WebVR API（已被 WebXR Device API 取代）中定义。它不再有望成为标准。

在所有浏览器都实现新的 WebXR API (en-US) 之前，建议使用框架（如：A-Frame、Babylon.js 或 Three.js）或 polyfill 来开发适用于所有浏览器的 WebXR 应用程序。[1]

Browser compatibility

BCD tables only load in the browser