rendering performance improvements (#968)

* freeze objects

* component rendering perf work

* use PureComponent where safe

* remove obsolete WorldUtil code

* make brushable histogram a pure component

client/src/util/dataframe/dataframe.js

@@ -127,6 +127,7 @@ class Dataframe {
     this.__id = Dataframe.__getId();
 
     this.__compile(__columnsAccessor);
+    Object.freeze(this);
   }
 
   static __errorChecks(dims, columnarData, rowIndex, colIndex) {
@@ -269,6 +270,7 @@ class Dataframe {
     get.iget = iget;
     get.__id = __id;
 
+    Object.freeze(get);
     return get;
   }
 
@@ -288,6 +290,7 @@ class Dataframe {
       }
       return Dataframe.__compileColumn(column, getRowByOffset, getRowByLabel);
     });
+    Object.freeze(this.__columnsAccessor);
   }
 
   clone() {

client/src/util/stateManager/index.js

@@ -17,7 +17,6 @@ exists to support those concepts.
 export * as ColorHelpers from "./colorHelpers";
 export * as Universe from "./universe";
 export * as World from "./world";
-export * as WorldUtil from "./worldUtil";
 export * as ControlsHelpers from "./controlsHelpers";
 export * as AnnotationsHelpers from "./annotationsHelpers";
 export * as SchemaHelpers from "./schemaHelpers";

client/src/util/stateManager/worldUtil.js

@@ -1,75 +0,0 @@
-/* eslint-disable import/prefer-default-export */
-import _ from "lodash";
-
-/*
-Various utility functions operating on World/Universe
-*/
-
-/*
-Count unique category values, binning first by dim1 then by dim2
-Return:
-
-Map {
-   dim1_val1: Map {
-      dim2_val1: number,
-      dim2_val2: number,
-      ...
-   },
-   ...
-}
-
-Parameters are:
-- dim1: dimension 1 name/label
-- dim2: dimension 2 name/label
-- df: dataframe containing dim1 and dim2 on the column axis
-
-*/
-function _countCategoryValues2D(dim1, dim2, df) {
-  const dimMap = new Map();
-  const col1 = df.col(dim1) ? df.col(dim1).asArray() : null;
-  const col2 = df.col(dim2) ? df.col(dim2).asArray() : null;
-  if (!col1 || !col2) {
-    return dimMap;
-  }
-
-  for (let r = 0, l = df.length; r < l; r += 1) {
-    const val1 = col1[r];
-    const val2 = col2[r];
-    let d2Map = dimMap.get(val1);
-    if (d2Map === undefined) {
-      d2Map = new Map();
-      dimMap.set(val1, d2Map);
-    }
-    let curCount = d2Map.get(val2);
-    if (curCount === undefined) {
-      curCount = 0;
-    }
-    d2Map.set(val2, curCount + 1);
-  }
-  return dimMap;
-}
-
-let __worldUtilMemoId__ = 0;
-function _memoizedId(x) {
-  if (!x.__worldUtilMemoId__) {
-    __worldUtilMemoId__ += 1;
-    x.__worldUtilMemoId__ = __worldUtilMemoId__;
-  }
-  return x.__worldUtilMemoId__;
-}
-function _countCategoryValues2DResolver(...args) {
-  const id = args[0] + args[1] + _memoizedId(args[2]);
-  return id;
-}
-
-export const countCategoryValues2D = _.memoize(
-  _countCategoryValues2D,
-  _countCategoryValues2DResolver
-);
-
-/*
-Clear any cached data within WorldUtil caches, eg, memoized functions
-*/
-export function clearCaches() {
-  countCategoryValues2D.cache.clear();
-}

client/src/util/typedCrossfilter/bitArray.js

@@ -35,6 +35,7 @@ class BitArray {
 
     this.bitmask = new Int32Array(this.width); // dimension allocation mask
     this.bitarray = new Int32Array(this.width * this.length);
+    Object.seal(this);
   }
 
   // Return the number of records that are selected, ie, have a one bit in

client/src/util/typedCrossfilter/crossfilter.js

@@ -47,6 +47,7 @@ export default class ImmutableTypedCrossfilter {
     this.data = data;
     this.selectionCache = selectionCache; /* BitArray */
     this.dimensions = dimensions; /* name: { id, dim, name, selection } */
+    Object.preventExtensions(this);
   }
 
   size() {
@@ -94,6 +95,7 @@ export default class ImmutableTypedCrossfilter {
     }
     const DimensionType = DimTypes[type];
     const dim = new DimensionType(name, data, ...rest);
+    Object.freeze(dim);
     const dimensions = {
       ...this.dimensions,
       [name]: {