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diff --git a/client/splash/vendor/geometry_helper.js b/client/splash/vendor/geometry_helper.js
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+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+/**
+ * @fileoverview Helper class implementing various utilities for THREE.js
+ * geometry.
+ */
+
+function GeometryHelper() {}
+
+GeometryHelper.prototype = {
+    constructor: GeometryHelper,
+
+    // Computes vertex normals on THREE.js buffer geometry, even when the mesh
+    // uses triangle strip connectivity.
+    computeVertexNormals: function (bufferGeometry) {
+      if (bufferGeometry.drawMode === THREE.TrianglesDrawMode) {
+        bufferGeometry.computeVertexNormals();
+        return;
+      } else if (bufferGeometry.drawMode === THREE.TriangleStripDrawMode) {
+        if (bufferGeometry.attributes.position === undefined) {
+          return;
+        }
+        const inPositions = bufferGeometry.attributes.position.array;
+        if (bufferGeometry.attributes.normal === undefined) {
+          bufferGeometry.addAttribute(
+              'normal',
+              new THREE.BufferAttribute(new Float32Array(inPositions.length),
+                                        3));
+        } else {
+          // Reset existing normals to zero.
+          const array = bufferGeometry.attributes.normal.array;
+          for (let i = 0; i < array.length; ++i) {
+            array[ i ] = 0;
+          }
+        }
+        let outNormals = bufferGeometry.attributes.normal.array;
+
+        let pos0 = new THREE.Vector3();
+        let pos1 = new THREE.Vector3();
+        let pos2 = new THREE.Vector3();
+        let posDif0 = new THREE.Vector3(), posDif1 = new THREE.Vector3();
+        let localNormal = new THREE.Vector3();
+
+        const stripIndices = bufferGeometry.index.array;
+        for (let i = 2; i < stripIndices.length; ++i) {
+          let index0 = stripIndices[i - 2] * 3;
+          let index1 = stripIndices[i - 1] * 3;
+          let index2 = stripIndices[i] * 3;
+          // Skip degenerate triangles.
+          if (index0 === index1 || index0 === index2 || index1 === index2) {
+            continue;
+          }
+          if ((i & 1) !== 0) {
+            // Swap index 1 and 0 on odd indexed triangles.
+            const tmpIndex = index1;
+            index1 = index2;
+            index2 = tmpIndex;
+          }
+
+          // Get position values.
+          pos0.fromArray(inPositions, index0);
+          pos1.fromArray(inPositions, index1);
+          pos2.fromArray(inPositions, index2);
+
+          // Position differences
+          posDif0.subVectors(pos2, pos0);
+          posDif1.subVectors(pos1, pos0);
+
+          // Weighted normal.
+          localNormal.crossVectors(posDif1, posDif0);
+
+          // Update normals on vertices
+          outNormals[index0] += localNormal.x;
+          outNormals[index0 + 1] += localNormal.y;
+          outNormals[index0 + 2] += localNormal.z;
+
+          outNormals[index1] += localNormal.x;
+          outNormals[index1 + 1] += localNormal.y;
+          outNormals[index1 + 2] += localNormal.z;
+
+          outNormals[index2] += localNormal.x;
+          outNormals[index2 + 1] += localNormal.y;
+          outNormals[index2 + 2] += localNormal.z;
+        }
+        bufferGeometry.normalizeNormals();
+        bufferGeometry.attributes.normal.needsUpdate = true;
+      }
+    },
+};