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import EventHandlerBase from './fill/EventHandlerBase.js'
/*
A Reality represents a view of the world, be it the real world via sensors or a virtual world that is rendered with WebGL or WebGPU.
*/
export default class Reality extends EventHandlerBase {
constructor(xr, name, isShared, isPassthrough){
super()
this._xr = xr
this._name = name
this._isShared = isShared
this._isPassthrough = isPassthrough
this._anchors = new Map()
}
get name(){ return this._name }
get isShared(){ return this._isShared }
get isPassthrough(){ return this._isPassthrough }
getCoordinateSystem(...types){
//XRCoordinateSystem? getCoordinateSystem(XRFrameOfReferenceType type, ...); // Tries the types in order, returning the first match or null if none is found
throw new Error('Not implemented')
}
/*
Called when at least one active XRSession is using this Reality
*/
_start(){
throw new Error('Exending classes should implement _start')
}
/*
Called when no more active XRSessions are using this Reality
*/
_stop(){
throw new Error('Exending classes should implement _stop')
}
/*
Called by a session before it hands a new XRPresentationFrame to the app
*/
_handleNewFrame(){}
/*
Create an anchor hung in space
*/
_addAnchor(anchor, display){
// returns DOMString anchor UID
throw new Error('Exending classes should implement _addAnchor')
}
/*
Create an anchor attached to a surface, as found by a ray
returns a Promise that resolves either to an AnchorOffset or null if the hit test failed
normalized screen x and y are in range 0..1, with 0,0 at top left and 1,1 at bottom right
*/
_findAnchor(normalizedScreenX, normalizedScreenY, display){
throw new Error('Exending classes should implement _findAnchor')
}
/*
Find an XRAnchorOffset that is at floor level below the current head pose
returns a Promise that resolves either to an AnchorOffset or null if the floor level is unknown
*/
_findFloorAnchor(display, uid=null){
// Copy the head model matrix for the current pose so we have it in the promise below
const headModelMatrix = new Float32Array(display._headPose.poseModelMatrix)
return new Promise((resolve, reject) => {
// For now, just create an anchor at origin level. Maybe in the future search for a surface?
const coordinates = new XRCoordinates(display, display._trackerCoordinateSystem)
headModelMatrix[13] = 0 // Set height to 0
coordinates.poseMatrix = headModelMatrix
const anchor = new XRAnchor(coordinates, uid)
this._addAnchor(anchor, display)
resolve(new XRAnchorOffset(anchor.uid))
})
}
_getAnchor(uid){
return this._anchors.get(uid) || null
}
_removeAnchor(uid){
// returns void
throw new Error('Exending classes should implement _removeAnchor')
}
// attribute EventHandler onchange;
}