improve calculateInvariantBoundingSphere

src/mol-gl/renderable/util.ts

 /**
- * Copyright (c) 2018-2022 mol* contributors, licensed under MIT, See LICENSE file for more info.
+ * Copyright (c) 2018-2023 mol* contributors, licensed under MIT, See LICENSE file for more info.
  *
  * @author Alexander Rose <alexander.rose@weirdbyte.de>
  */
@@ -10,6 +10,10 @@ import { BoundaryHelper } from '../../mol-math/geometry/boundary-helper';
 import { TextureFilter } from '../webgl/texture';
 import { arrayMinMax } from '../../mol-util/array';
 
+// avoiding namespace lookup improved performance in Chrome (Aug 2020)
+const v3fromArray = Vec3.fromArray;
+const v3transformMat4Offset = Vec3.transformMat4Offset;
+
 export function calculateTextureInfo(n: number, itemSize: number) {
     n = Math.max(n, 2); // observed issues with 1 pixel textures
     const sqN = Math.sqrt(n);
@@ -137,21 +141,21 @@ export function calculateInvariantBoundingSphere(position: Float32Array, positio
 
     boundaryHelper.reset();
     for (let i = 0, _i = positionCount * 3; i < _i; i += step) {
-        Vec3.fromArray(v, position, i);
+        v3fromArray(v, position, i);
         boundaryHelper.includePosition(v);
     }
     boundaryHelper.finishedIncludeStep();
     for (let i = 0, _i = positionCount * 3; i < _i; i += step) {
-        Vec3.fromArray(v, position, i);
+        v3fromArray(v, position, i);
         boundaryHelper.radiusPosition(v);
     }
 
     const sphere = boundaryHelper.getSphere();
 
-    if (positionCount <= 98) {
+    if (positionCount <= 14) {
         const extrema: Vec3[] = [];
         for (let i = 0, _i = positionCount * 3; i < _i; i += step) {
-            extrema.push(Vec3.fromArray(Vec3(), position, i));
+            extrema.push(v3fromArray(Vec3(), position, i));
         }
         Sphere3D.setExtrema(sphere, extrema);
     }
@@ -174,28 +178,28 @@ export function calculateTransformBoundingSphere(invariantBoundingSphere: Sphere
     const { center, radius, extrema } = invariantBoundingSphere;
 
     // only use extrema if there are not too many transforms
-    if (extrema && transformCount < 50) {
+    if (extrema && transformCount <= 14) {
         for (let i = 0, _i = transformCount; i < _i; ++i) {
             for (const e of extrema) {
-                Vec3.transformMat4Offset(v, e, transform, 0, 0, i * 16);
+                v3transformMat4Offset(v, e, transform, 0, 0, i * 16);
                 boundaryHelper.includePosition(v);
             }
         }
         boundaryHelper.finishedIncludeStep();
         for (let i = 0, _i = transformCount; i < _i; ++i) {
             for (const e of extrema) {
-                Vec3.transformMat4Offset(v, e, transform, 0, 0, i * 16);
+                v3transformMat4Offset(v, e, transform, 0, 0, i * 16);
                 boundaryHelper.radiusPosition(v);
             }
         }
     } else {
         for (let i = 0, _i = transformCount; i < _i; ++i) {
-            Vec3.transformMat4Offset(v, center, transform, 0, 0, i * 16);
+            v3transformMat4Offset(v, center, transform, 0, 0, i * 16);
             boundaryHelper.includePositionRadius(v, radius);
         }
         boundaryHelper.finishedIncludeStep();
         for (let i = 0, _i = transformCount; i < _i; ++i) {
-            Vec3.transformMat4Offset(v, center, transform, 0, 0, i * 16);
+            v3transformMat4Offset(v, center, transform, 0, 0, i * 16);
             boundaryHelper.radiusPositionRadius(v, radius);
         }
     }