Matrix performance

CHANGES.md

@@ -9,6 +9,10 @@
 - `scene.drillPick` now uses a breadth-first search strategy instead of depth-first. This may change which entities are picked when
   using large values of `width` and `height` when providing a `limit`, prioritizing entities closer to the camera.
 
+#### Additions :tada:
+
+- Matrices are now backed by `Float64Array`'s, making operations up to 2x faster, resulting in performance improvements across the board. [#12973](https://github.com/CesiumGS/cesium/pull/12973)
+
 #### Fixes :wrench:
 
 - Fix issues with label background when updating properties while `label.show` is `false`. [#12138](https://github.com/CesiumGS/cesium/issues/12138)

packages/engine/Source/Core/Matrix3.js

@@ -2,6 +2,7 @@ import Cartesian3 from "./Cartesian3.js";
 import Check from "./Check.js";
 import defined from "./defined.js";
 import DeveloperError from "./DeveloperError.js";
+import freezeMatrix from "./freezeMatrix.js";
 import CesiumMath from "./Math.js";
 
 /**
@@ -35,28 +36,30 @@ import CesiumMath from "./Math.js";
  * @see Matrix2
  * @see Matrix4
  */
-function Matrix3(
-  column0Row0,
-  column1Row0,
-  column2Row0,
-  column0Row1,
-  column1Row1,
-  column2Row1,
-  column0Row2,
-  column1Row2,
-  column2Row2,
-) {
-  this[0] = column0Row0 ?? 0.0;
-  this[1] = column0Row1 ?? 0.0;
-  this[2] = column0Row2 ?? 0.0;
-  this[3] = column1Row0 ?? 0.0;
-  this[4] = column1Row1 ?? 0.0;
-  this[5] = column1Row2 ?? 0.0;
-  this[6] = column2Row0 ?? 0.0;
-  this[7] = column2Row1 ?? 0.0;
-  this[8] = column2Row2 ?? 0.0;
+class Matrix3 extends Float64Array {
+  constructor(
+    column0Row0,
+    column1Row0,
+    column2Row0,
+    column0Row1,
+    column1Row1,
+    column2Row1,
+    column0Row2,
+    column1Row2,
+    column2Row2,
+  ) {
+    super(9);
+    this[0] = column0Row0 ?? 0.0;
+    this[1] = column0Row1 ?? 0.0;
+    this[2] = column0Row2 ?? 0.0;
+    this[3] = column1Row0 ?? 0.0;
+    this[4] = column1Row1 ?? 0.0;
+    this[5] = column1Row2 ?? 0.0;
+    this[6] = column2Row0 ?? 0.0;
+    this[7] = column2Row1 ?? 0.0;
+    this[8] = column2Row2 ?? 0.0;
+  }
 }
-
 /**
  * The number of elements used to pack the object into an array.
  * @type {number}
@@ -1665,26 +1668,6 @@ Matrix3.equalsEpsilon = function (left, right, epsilon) {
   );
 };
 
-/**
- * An immutable Matrix3 instance initialized to the identity matrix.
- *
- * @type {Matrix3}
- * @constant
- */
-Matrix3.IDENTITY = Object.freeze(
-  new Matrix3(1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0),
-);
-
-/**
- * An immutable Matrix3 instance initialized to the zero matrix.
- *
- * @type {Matrix3}
- * @constant
- */
-Matrix3.ZERO = Object.freeze(
-  new Matrix3(0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0),
-);
-
 /**
  * The index into Matrix3 for column 0, row 0.
  *
@@ -1835,4 +1818,25 @@ Matrix3.prototype.toString = function () {
     `(${this[2]}, ${this[5]}, ${this[8]})`
   );
 };
+
+/**
+ * An immutable Matrix3 instance initialized to the identity matrix.
+ *
+ * @type {Readonly<Matrix3>}
+ * @constant
+ */
+Matrix3.IDENTITY = freezeMatrix(
+  new Matrix3(1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0),
+);
+
+/**
+ * An immutable Matrix3 instance initialized to the zero matrix.
+ *
+ * @type {Readonly<Matrix3>}
+ * @constant
+ */
+Matrix3.ZERO = freezeMatrix(
+  new Matrix3(0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0),
+);
+
 export default Matrix3;