From de2139106245304cf0703d12df63c8b91d89ec61 Mon Sep 17 00:00:00 2001
From: Andrew Meadows <andrew@highfidelity.io>
Date: Fri, 7 Jul 2017 09:59:13 -0700
Subject: [PATCH] add script to measure cost of entity lookup by id

---
 .../tests/entityLookupCostMeasurement.js      | 104 ++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 scripts/developer/tests/entityLookupCostMeasurement.js

diff --git a/scripts/developer/tests/entityLookupCostMeasurement.js b/scripts/developer/tests/entityLookupCostMeasurement.js
new file mode 100644
index 0000000000..15697fe13d
--- /dev/null
+++ b/scripts/developer/tests/entityLookupCostMeasurement.js
@@ -0,0 +1,104 @@
+// Creates a large number of entities on the cardinal planes of the octree (all
+// objects will live in the root octree element).  Measures how long it takes
+// to update the properties of the first and last entity.  The difference
+// between the two measurements shows how the cost of lookup changes as a
+// function of the number of entities.  For best results run this in an
+// otherwise empty domain.
+
+var firstId;
+var lastId;
+var NUM_ENTITIES_ON_SIDE = 25;
+
+// create the objects
+createObjects = function () {
+    var STRIDE = 0.75;
+    var WIDTH = 0.5;
+    var DIMENSIONS = { x: WIDTH, y: WIDTH, z: WIDTH };
+    var LIFETIME = 20;
+
+    var properties = {
+        name: "",
+        type : "Box",
+        dimensions : DIMENSIONS,
+        position : { x: 0, y: 0, z: 0},
+        lifetime : LIFETIME,
+        color : { red:255, green: 64, blue: 255 }
+    };
+
+    // xy
+    var planeName = "xy";
+    for (var i = 0; i < NUM_ENTITIES_ON_SIDE; ++i) {
+        for (var j = 0; j < NUM_ENTITIES_ON_SIDE; ++j) {
+            properties.name = "Box-" + planeName + "-" + i + "." + j;
+            properties.position = { x: i * STRIDE, y: j * STRIDE, z: 0 };
+            var red = i * 255 / NUM_ENTITIES_ON_SIDE;
+            var green = j * 255 / NUM_ENTITIES_ON_SIDE;
+            var blue = 0;
+            properties.color = { red: red, green: green, blue: blue };
+            if (i == 0 && j == 0) {
+                firstId = Entities.addEntity(properties);
+            } else {
+                Entities.addEntity(properties);
+            }
+        }
+    }
+
+    // yz
+    var planeName = "yz";
+    for (var i = 0; i < NUM_ENTITIES_ON_SIDE; ++i) {
+        for (var j = 0; j < NUM_ENTITIES_ON_SIDE; ++j) {
+            properties.name = "Box-" + planeName + "-" + i + "." + j;
+            properties.position = { x: 0, y: i * STRIDE, z: j * STRIDE };
+            var red = 0;
+            var green = i * 255 / NUM_ENTITIES_ON_SIDE;
+            var blue = j * 255 / NUM_ENTITIES_ON_SIDE;
+            properties.color = { red: red, green: green, blue: blue };
+            Entities.addEntity(properties);
+        }
+    }
+
+    // zx
+    var planeName = "zx";
+    for (var i = 0; i < NUM_ENTITIES_ON_SIDE; ++i) {
+        for (var j = 0; j < NUM_ENTITIES_ON_SIDE; ++j) {
+            properties.name = "Box-" + planeName + "-" + i + "." + j;
+            properties.position = { x: j * STRIDE, y: 0, z: i * STRIDE };
+            var red = j * 255 / NUM_ENTITIES_ON_SIDE;
+            var green = 0;
+            var blue = i * 255 / NUM_ENTITIES_ON_SIDE;
+            properties.color = { red: red, green: green, blue: blue };
+            lastId = Entities.addEntity(properties);
+        }
+    }
+};
+
+createObjects();
+
+// measure the time it takes to edit the first and last entities many times
+// (requires a lookup by entityId each time)
+changeProperties = function (id) {
+    var newProperties = { color : { red: 255, green: 255, blue: 255 } };
+    Entities.editEntity(id, newProperties);
+}
+
+// first
+var NUM_CHANGES = 10000;
+var firstStart = Date.now();
+for (var k = 0; k < NUM_CHANGES; ++k) {
+    changeProperties(firstId);
+}
+var firstEnd = Date.now();
+var firstDt = firstEnd - firstStart;
+
+// last
+var lastStart = Date.now();
+for (var k = 0; k < NUM_CHANGES; ++k) {
+    changeProperties(lastId);
+}
+var lastEnd = Date.now();
+var lastDt = lastEnd - lastStart;
+
+// print the results
+var numEntities = 3 * NUM_ENTITIES_ON_SIDE * NUM_ENTITIES_ON_SIDE;
+print("numEntities = " + numEntities + "  numEdits = " + NUM_CHANGES + "  firstDt = " + firstDt + "  lastDt = " + lastDt);
+