Minor fixes and guard clauses

TODO: Bootstrap ms-* and ps-* can't account for all possible levels of indentation/nesting...

js/scene.js

@@ -93,10 +93,10 @@ function loadNodes(nodes) {
             AppState.clipping.boundingSphere = node.getBound();
         }
 
-        if (!AppState.clipping.boundingSphere) {
-            console.error("There is no computed bounding sphere, clipping will fail. Missing main node?");
-        }
-
         AppState.nodes.push({id: n.label, active: true});
     });
+    
+    if (!AppState.clipping.boundingSphere) {
+        console.error("No bounding sphere computed, clipping will fail. Ensure one node has 'isMain: true'.");
+    }
 }

js/ui.js

@@ -166,8 +166,8 @@ function toggleSettingsPanel(triggerId) {
             <label class="form-check-label" for="shadowsSwitch">Ombre <i class="bi bi-info-circle ms-2 c-hand" title=""></i></label>
         `;
 
-        shadowsSwitch.querySelector('input[type="checkbox"').checked = AppState.shadows;
-        ambientOcclSwitch.querySelector('input[type="checkbox"').checked = AppState.ambientOcclusion;
+        shadowsSwitch.querySelector('input[type="checkbox"]').checked = AppState.shadows;
+        ambientOcclSwitch.querySelector('input[type="checkbox"]').checked = AppState.ambientOcclusion;
 
         ATON.UI.elSidePanel.appendChild(ambientOcclSwitch);
         ATON.UI.elSidePanel.appendChild(shadowsSwitch);

js/utils/clipping.js

@@ -131,6 +131,8 @@ function updateClipper (vector, point) {
 export function resetClipping () {
     AppState.clipping.enabled = false;
     ATON.disableClipPlanes();
+
+    if (AppState.clipping.controls) {
         AppState.clipping.controls.deactivate();
         // Manually remove event listeners from DragControls!!
         AppState.renderer.domElement.removeEventListener( 'pointermove', AppState.clipping.controls.onPointerMove );
@@ -138,9 +140,13 @@ export function resetClipping () {
         AppState.renderer.domElement.removeEventListener( 'pointerup', AppState.clipping.controls.onPointerCancel );
         AppState.renderer.domElement.removeEventListener( 'pointerleave', AppState.clipping.controls.onPointerCancel )
         AppState.clipping.controls = null;
+    }
+
+    if (AppState.clipping.helper) {
         AppState.clipping.helper.removeFromParent();
         AppState.root.remove(AppState.clipping.helper);
         AppState.clipping.helper = null;
+    }
     AppState.clipping.plane = null;
     AppState.clipping.vector = null;
     // Ensure nav controls are reactivated!