files/en-us/web/api/xrviewport/y/index.md
{{APIRef("WebXR Device API")}}{{SecureContext_Header}}
The read-only {{domxref("XRViewport")}} interface's
y property indicates the offset from the bottom edge of
the destination surface (typically a {{domxref("XRWebGLLayer")}}) to the bottom edge of
the viewport within the surface into which WebXR content is to be rendered. The
viewport's {{domxref("XRViewport.x", "x")}} property identifies the x
component of the origin, and its is given by the {{domxref("XRViewPort.width", "width")}}
and {{domxref("XRViewport.height", "height")}} properties.
The offset from the bottom edge of the rendering surface to the bottom edge of the viewport, in pixels.
[!NOTE] Although other web APIs typically consider the
yaxis to begin at the top and grow larger progressing downward, WebGL reverses this, withygrowing larger as it goes upward on the screen.
See the main {{domxref("XRViewport")}} page for examples.
{{Specifications}}
{{Compat}}