refactor: only add ar-hit-test if not disabled

This conforms to the proper pattern of only adding webxr features through
systems/components

Author: hi-liang

index.html

@@ -50,8 +50,6 @@
             renderer="antialias: true; maxCanvasWidth: 3840; maxCanvasHeight: 3840;"
             webxr="optionalFeatures: dom-overlay, computerVision, mesh-detection, plane-detection; overlayElement: overlay;"
             webxr-device-manager
-            ar-hit-test="enabled:true; src: static/images/blank-pixel.png; mapSize: 0.005 0.005;"
-            ar-hit-test-listener
             gltf-model="dracoDecoderPath: /static/vendor/draco-1.5.4/;"
             inspector="url: static/vendor/aframe-inspector.min.js;"
             xr-mode-ui="XRMode:xr"

src/systems/core/arena.js

@@ -680,9 +680,13 @@ AFRAME.registerSystem('arena-scene', {
                 }, 10);
             }
 
-            if (sceneOptions['ar-hit-test']?.enabled === false) {
-                sceneEl.removeAttribute('ar-hit-test-listener');
-                sceneEl.removeAttribute('ar-hit-test');
+            if (sceneOptions['ar-hit-test']?.enabled !== false) {
+                sceneEl.setAttribute('ar-hit-test', {
+                    enabled: true,
+                    src: 'static/images/blank-pixel.png',
+                    mapSize: { x: 0.005, y: 0.005 },
+                });
+                sceneEl.setAttribute('ar-hit-test-listener', { enabled: true });
             }
 
             // deal with scene attribution