在此页

• 句法
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

这是 实验性技术
检查 浏览器兼容性表格 要小心谨慎在生产中使用这之前。

leftBounds 特性为 VRLayerInit interface (dictionary) defines the left texture bounds of the canvas whose contents will be presented by the VRDisplay .

句法

var myVRLayerInit = { };
myVRLayerInit.leftBounds = [0.0, 0.0, 0.5, 1.0];
					

值

An array of four floating point values, which can take values from 0.0–1.0:

• The left offset of the bounds.
• The top offset of the bounds.
• The width of the bounds.
• The height of the bounds.

若 leftBounds is not specified in the dictionary, the default value used is [0.0, 0.0, 0.5, 1.0] .

范例

// currently returns an empty array
var layers = vrDisplay.getLayers();
if(navigator.getVRDisplays) {
  console.log('WebVR 1.1 supported');
  // Then get the displays attached to the computer
  navigator.getVRDisplays().then(function(displays) {
    // If a display is available, use it to present the scene
    if(displays.length > 0) {
      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', function() {
        vrDisplay.requestPresent([{ source: canvas }]).then(function() {
          console.log('Presenting to WebVR display');
          // Here it returns an array of VRLayerInit objects
          var layers = vrDisplay.getLayers();
          ...
        });
      });
    }
  });
}
					

VRLayerInit objects look something like this:

{
  leftBounds : [ ... ],
  rightBounds: [ ... ],
  source: canvasReference
}
					

注意 ： canvasReference refers to the <canvas> element itself, not the WebGL context associated with the canvas. The other two members are arrays

规范

规范	状态	注释
WebVR 1.1 The definition of 'leftBounds' in that specification.	草案	初始定义

浏览器兼容性

更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
leftBounds 弃用	Chrome No	Edge ≤18 — 79	Firefox 55 55 Windows support was enabled in Firefox 55. 64 macOS support was enabled in Firefox 64.	IE No	Opera ?	Safari No	WebView Android No	Chrome Android 56 — 80 Disabled 不支持 56 — 80 Disabled Only works in an experimental version of Chrome . (Other builds won't return any devices when Navigator.getVRDisplays() is invoked.) Daydream View supported in Chrome 56. Google Cardboard supported in Chrome 57. Disabled From version 56 until version 80 (exclusive): this feature is behind the WebVR preference. To change preferences in Chrome, visit chrome://flags.	Firefox Android 55	Opera Android ?	Safari iOS ?	Samsung Internet Android 6.0 6.0 Google Cardboard supported in Samsung Internet 7.0.

图例

完整支持

完整支持

不支持

不支持

兼容性未知 ?

兼容性未知

实验。期望将来行为有所改变。

实验。期望将来行为有所改变。

弃用。不要用于新网站。

弃用。不要用于新网站。

见实现注意事项。

用户必须明确启用此特征。

用户必须明确启用此特征。

另请参阅

• WebVR API homepage
• MozVr.com — demos, downloads, and other resources from the Mozilla VR team.

元数据

• 最后修改： 2019 年 3 月 23 日

相关话题

1. WebVR API
2. VRLayerInit
3. 特性

   1. leftBounds
   2. rightBounds
   3. source
4. Related pages for WebVR API

   1. Gamepad.displayId
   2. Navigator.activeVRDisplays
   3. Navigator.getVRDisplays()
   4. VRDisplay
   5. VRDisplayCapabilities
   6. VRDisplayEvent
   7. VREyeParameters
   8. VRFieldOfView
   9. VRFrameData
   10. VRPose
   11. VRStageParameters