PositionSensorVRDevice: getImmediateState() method
Deprecated
Avoid using this feature in new projects. Development of the WebVR API halted in favor of WebXR. This feature may be a candidate for removal from web standards or browsers.
Consider using the following features instead: WebXR.
Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.
The getImmediateState() method of the VRDisplay interface returns the current instantaneous position sensor state. This is intended to only be used rarely, for certain special uses, for example sampling the immediate position of a hand orientation sensor — or at least it will be, in the future.
For most standard uses, you'll probably want to use PositionSensorVRDevice.getState instead.
Syntax
getImmediateState()
Parameters
None.
Return value
A VRPose object.
Examples
The following demo uses the WebVR API to update the view of a simple CanvasRenderingContext2D scene on each frame of a requestAnimationFrame loop. The main function that updates the view data is as follows:
function setView() {
const posState = gPositionSensor.getImmediateState();
if (posState.hasPosition) {
posPara.textContent = `Position: x${roundToTwo(
posState.position.x,
)} y${roundToTwo(posState.position.y)} z${roundToTwo(posState.position.z)}`;
xPos = -posState.position.x * WIDTH * 2;
yPos = posState.position.y * HEIGHT * 2;
zPos = -posState.position.z > 0.01 ? -posState.position.z : 0.01;
}
if (posState.hasOrientation) {
orientPara.textContent = `Orientation: x${roundToTwo(
posState.orientation.x,
)} y${roundToTwo(posState.orientation.y)} z${roundToTwo(
posState.orientation.z,
)}`;
xOrient = posState.orientation.x * WIDTH;
yOrient = -posState.orientation.y * HEIGHT * 2;
zOrient = posState.orientation.z * 180;
}
}
Here we are grabbing a VRPose object using getImmediateState() and storing it in posState (the actual live demo uses getState(), but both seem to do the same thing currently.) We then check to make sure that position and orientation info is present in the current frame using VRPose.position and VRPose.orientation (these return null if, for example the head mounted display is turned off or not pointing at the position sensor, which would cause an error.)
We then output the x, y and z position and orientation values for informational purposes, and use those values to update the xPos, yPos, zPos, xOrient, yOrient, and zOrient variables, which are used to update the scene rendering on each frame.