Limited availability
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
The WebXR Device API's XRViewport
interface provides properties used to describe the size and position of the current viewport within the XRWebGLLayer
being used to render the 3D scene.
height
Read only
The height, in pixels, of the viewport.
width
Read only
The width, in pixels, of the viewport.
x
Read only
The offset from the origin of the destination graphics surface (typically a XRWebGLLayer
) to the left edge of the viewport, in pixels.
y
Read only
The offset from the origin of the viewport to the bottom edge of the viewport; WebGL's coordinate system places (0, 0) at the bottom left corner of the surface.
Currently, the only type of surface available is the XRWebGLLayer
. The precise orientation of the coordinate system may vary with other surface types, but in WebGL, the origin (0, 0) is located at the bottom-left corner of the surface. Thus the values specified in an XRViewport
define a rectangle whose bottom-left corner is at (x
, y
) and which extends width
pixels toward the left and height
pixels upward.
These values may be passed directly into the WebGLRenderingContext.viewport()
method:
const xrViewport = xrWebGLLayer.getViewport(xrView);
gl.viewport(xrViewport.x, xrViewport.y, xrViewport.width, xrViewport.height);
Example
This example sets up an animation frame callback using requestAnimationFrame()
. After initial setup, it iterates over each of the views within the viewer's pose, configuring the viewport as dictated by the XRWebGLLayer
.
xrSession.requestAnimationFrame((time, xrFrame) => {
const viewerPose = xrFrame.getViewerPose(xrReferenceSpace);
gl.bindFramebuffer(xrWebGLLayer.framebuffer);
for (const xrView of viewerPose.views) {
const xrViewport = xrWebGLLayer.getViewport(xrView);
gl.viewport(
xrViewport.x,
xrViewport.y,
xrViewport.width,
xrViewport.height,
);
// Now we can use WebGL to draw into a viewport matching
// the viewer's needs
}
});
Specifications Browser compatibility
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4