Examples: Expand vertex normals update to include neighbors.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: mrdoob

examples/jsm/sculpt/Sculpt.js

@@ -287,8 +287,9 @@ class Sculpt {
 		}
 
 		const result = new Uint32Array( iVertsInRadius.subarray( 0, acc ) );
-		sm.updateTopology( iFaces, iVerts );
-		sm._updateGeometry( iFaces, iVerts );
+		const iVertsExpanded = sm.getVerticesFromFaces( iFaces );
+		sm.updateTopology( iFaces, iVertsExpanded );
+		sm._updateGeometry( iFaces, iVertsExpanded );
 		return result;
 
 	}
@@ -402,9 +403,10 @@ class Sculpt {
 
 		}
 
-		// Update geometry
+		// Update geometry (expand verts to include neighbors for correct normals)
 		const iFaces = sm.getFacesFromVertices( iVerts );
-		sm._updateGeometry( iFaces, iVerts );
+		const iVertsExpanded = sm.getVerticesFromFaces( iFaces );
+		sm._updateGeometry( iFaces, iVertsExpanded );
 
 	}
 
@@ -499,7 +501,8 @@ class Sculpt {
 			const iVertsDyn = this._dynamicTopology( iVerts );
 			toolDrag( sm, iVertsDyn, this._interPoint, this._rLocal2, this._dragDir );
 			const iFaces = sm.getFacesFromVertices( iVertsDyn );
-			sm._updateGeometry( iFaces, iVertsDyn );
+			const iVertsExpanded = sm.getVerticesFromFaces( iFaces );
+			sm._updateGeometry( iFaces, iVertsExpanded );
 
 		}