XRWebGLLayer: fixedFoveation property

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

See full compatibility

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

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The fixedFoveation property of the XRWebGLLayer interface is a number indicating the amount of foveation used by the XR compositor. Fixed Foveated Rendering (FFR) renders the edges of the eye textures at a lower resolution than the center and reduces the GPU load.

It is most useful for low contrast textures, such as background images but less for high contrast ones such as text or detailed images. Authors can adjust the level on a per frame basis to achieve the best tradeoff between performance and visual quality.

Value

A number between 0 and 1.

The minimum amount of foveation is indicated by 0 (full resolution).
The maximum amount of foveation is indicated by 1 (the edges render at lower resolution).

It's up to the user agent how to interpret the numbers in this range. When changing the foveation level, the effect will visible in the next XRFrame.

Note that some user agents might implement certain levels of foveation, so you might need to adjust the foveation level in large increments to see an effect. Example levels:

0: no foveation
1/3: low foveation
2/3: medium foveation
1.0: maximum foveation

Some devices don't support foveated rendering. In that case fixedFoveation is null and setting it will not do anything.

Examples

Dynamically setting the level of fixed foveation rendering

The fixedFoveation property allows you to set the level of foveation at runtime and for each frame. To set the maximum foveation for a given XRWebGLLayer, use a value of 1.

let glLayer = xrSession.renderState.baseLayer;
glLayer.fixedFoveation = 1; // maximum foveation

Specifications

Specification
WebXR Device API # dom-xrwebgllayer-fixedfoveation

Browser compatibility

	desktop					mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on iOS	Samsung Internet	WebView Android	WebView on iOS
`fixedFoveation` Experimental	Chrome – No support Chrome footnote No support	Edge – No support Edge footnote No support	Firefox – No support Firefox footnote No support	Opera – No support Opera footnote No support	Safari – No support Safari footnote No support	Chrome Android – No support Chrome Android footnote No support	Firefox for Android – No support Firefox for Android footnote No support	Opera Android – No support Opera Android footnote No support	Safari on iOS – No support Safari on iOS footnote No support	Samsung Internet – No support Samsung Internet footnote No support	WebView Android – No support WebView Android footnote No support	WebView on iOS – No support WebView on iOS footnote No support

Tip: you can click/tap on a cell for more information.

No support: No support
: Experimental. Expect behavior to change in the future.