WebXR XRSession.enabledFeatures missing workaround

examples/src/examples/xr/ar-anchors-persistence/example.mjs

@@ -127,8 +127,8 @@ if (app.xr.supported) {
         }
     });
 
-    app.xr.on('start', function () {
-        message('Immersive AR session has started');
+    app.xr.anchors.on('available', () => {
+        message('Anchors became available');
 
         // restore all persistent anchors
         if (app.xr.anchors.persistence) {
@@ -138,6 +138,10 @@ if (app.xr.supported) {
             }
         }
     });
+
+    app.xr.on('start', function () {
+        message('Immersive AR session has started');
+    });
     app.xr.on('end', function () {
         message('Immersive AR session has ended');
     });

examples/src/examples/xr/ar-hit-test-anchors/example.mjs

@@ -133,9 +133,7 @@ if (app.xr.supported) {
         }
     });
 
-    app.xr.on('start', function () {
-        message('Immersive AR session has started');
-
+    app.xr.hitTest.on('available', () => {
         if (!app.xr.hitTest.supported || !app.xr.anchors.supported) return;
 
         // provide gaze-like way to create anchors
@@ -166,6 +164,10 @@ if (app.xr.supported) {
             createAnchor(lastHitTestResult);
         });
     });
+
+    app.xr.on('start', function () {
+        message('Immersive AR session has started');
+    });
     app.xr.on('end', function () {
         message('Immersive AR session has ended');
     });

examples/src/examples/xr/ar-hit-test/example.mjs

@@ -107,11 +107,7 @@ if (app.xr.supported) {
         }
     });
 
-    app.xr.on('start', function () {
-        message('Immersive AR session has started');
-
-        if (!app.xr.hitTest.supported) return;
-
+    app.xr.hitTest.on('available', () => {
         app.xr.hitTest.start({
             entityTypes: [pc.XRTRACKABLE_POINT, pc.XRTRACKABLE_PLANE],
             callback: function (err, hitTestSource) {
@@ -127,6 +123,10 @@ if (app.xr.supported) {
             }
         });
     });
+
+    app.xr.on('start', function () {
+        message('Immersive AR session has started');
+    });
     app.xr.on('end', function () {
         message('Immersive AR session has ended');
     });

package.json

@@ -56,6 +56,7 @@
       "twgsl": "readonly",
       "webkitAudioContext": "readonly",
       "XRRay": "readonly",
+      "XRRigidTransform": "readonly",
       "XRWebGLLayer": "readonly"
     },
     "parser": "@babel/eslint-parser",

src/framework/xr/xr-anchors.js

@@ -101,6 +101,12 @@ class XrAnchors extends EventHandler {
      */
     _available = false;
 
+    /**
+     * @type {boolean}
+     * @private
+     */
+    _checkingAvailability = false;
+
     /**
      * @type {boolean}
      * @private
@@ -283,7 +289,7 @@ class XrAnchors extends EventHandler {
                 });
         } else {
             this._creationQueue.push({
-                transform: new XRRigidTransform(position, rotation), // eslint-disable-line no-undef
+                transform: new XRRigidTransform(position, rotation),
                 callback: callback
             });
         }
@@ -380,8 +386,24 @@ class XrAnchors extends EventHandler {
      * @ignore
      */
     update(frame) {
-        if (!this._available)
+        if (!this._available) {
+            // enabledFeatures - is not available, requires alternative way to check feature availability
+            if (!this.manager.session.enabledFeatures && !this._checkingAvailability) {
+                this._checkingAvailability = true;
+
+                frame.createAnchor(new XRRigidTransform(), this.manager._referenceSpace)
+                    .then((xrAnchor) => {
+                        // successfully created an anchor - feature is available
+                        xrAnchor.delete();
+                        if (this.manager.active) {
+                            this._available = true;
+                            this.fire('available');
+                        }
+                    })
+                    .catch(() => { }); // stay unavailable
+            }
             return;
+        }
 
         // check if need to create anchors
         if (this._creationQueue.length) {

src/framework/xr/xr-hit-test.js

@@ -111,6 +111,12 @@ class XrHitTest extends EventHandler {
      */
     _available = false;
 
+    /**
+     * @type {boolean}
+     * @private
+     */
+    _checkingAvailability = false;
+
     /**
      * List of active {@link XrHitTestSource}.
      *
@@ -137,10 +143,29 @@ class XrHitTest extends EventHandler {
 
     /** @private */
     _onSessionStart() {
-        const available = this.manager.session.enabledFeatures.indexOf('hit-test') !== -1;
-        if (!available) return;
-        this._available = available;
-        this.fire('available');
+        if (this.manager.session.enabledFeatures) {
+            const available = this.manager.session.enabledFeatures.indexOf('hit-test') !== -1;
+            if (!available) return;
+            this._available = available;
+            this.fire('available');
+        } else if (!this._checkingAvailability) {
+            this._checkingAvailability = true;
+
+            // enabledFeatures - is not available, requires alternative way to check feature availability
+
+            this.manager.session.requestReferenceSpace(XRSPACE_VIEWER).then((referenceSpace) => {
+                this.manager.session.requestHitTestSource({
+                    space: referenceSpace
+                }).then((hitTestSource) => {
+                    hitTestSource.cancel();
+
+                    if (this.manager.active) {
+                        this._available = true;
+                        this.fire('available');
+                    }
+                }).catch(() => { });
+            }).catch(() => {});
+        }
     }
 
     /** @private */
@@ -316,6 +341,9 @@ class XrHitTest extends EventHandler {
      * @ignore
      */
     update(frame) {
+        if (!this._available)
+            return;
+
         for (let i = 0; i < this.sources.length; i++) {
             this.sources[i].update(frame);
         }

src/framework/xr/xr-mesh-detection.js

@@ -120,8 +120,14 @@ class XrMeshDetection extends EventHandler {
      * @ignore
      */
     update(frame) {
-        if (!this._supported || !this._available)
-            return;
+        if (!this._available) {
+            if (!this._manager.session.enabledFeatures && frame.detectedMeshes.size) {
+                this._available = true;
+                this.fire('available');
+            } else {
+                return;
+            }
+        }
 
         // add meshes
         for (const xrMesh of frame.detectedMeshes) {
@@ -159,10 +165,12 @@ class XrMeshDetection extends EventHandler {
 
     /** @private */
     _onSessionStart() {
-        const available = this._manager.session.enabledFeatures.indexOf('mesh-detection') !== -1;
-        if (!available) return;
-        this._available = available;
-        this.fire('available');
+        if (this._manager.session.enabledFeatures) {
+            const available = this._manager.session.enabledFeatures.indexOf('mesh-detection') !== -1;
+            if (!available) return;
+            this._available = available;
+            this.fire('available');
+        }
     }
 
     /** @private */

src/framework/xr/xr-plane-detection.js

@@ -117,10 +117,12 @@ class XrPlaneDetection extends EventHandler {
 
     /** @private */
     _onSessionStart() {
-        const available = this._supported && this._manager.session.enabledFeatures.indexOf('plane-detection') !== -1;
-        if (available) {
-            this._available = true;
-            this.fire('available');
+        if (this._manager.session.enabledFeatures) {
+            const available = this._manager.session.enabledFeatures.indexOf('plane-detection') !== -1;
+            if (available) {
+                this._available = true;
+                this.fire('available');
+            }
         }
     }
 
@@ -145,8 +147,14 @@ class XrPlaneDetection extends EventHandler {
      * @ignore
      */
     update(frame) {
-        if (!this._supported || !this._available)
-            return;
+        if (!this._available) {
+            if (!this._manager.session.enabledFeatures && frame.detectedPlanes.size) {
+                this._available = true;
+                this.fire('available');
+            } else {
+                return;
+            }
+        }
 
         const detectedPlanes = frame.detectedPlanes;
 

src/framework/xr/xr-views.js

@@ -261,6 +261,9 @@ class XrViews extends EventHandler {
         if (this._manager.type !== XRTYPE_AR)
             return;
 
+        if (!this._manager.session.enabledFeatures)
+            return;
+
         this._availableColor = this._manager.session.enabledFeatures.indexOf('camera-access') !== -1;
         this._availableDepth = this._manager.session.enabledFeatures.indexOf('depth-sensing') !== -1;