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diff --git a/devtools/client/memory/components/tree-map/drag-zoom.js b/devtools/client/memory/components/tree-map/drag-zoom.js
new file mode 100644
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+++ b/devtools/client/memory/components/tree-map/drag-zoom.js
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const { debounce } = require("sdk/lang/functional");
+const { lerp } = require("devtools/client/memory/utils");
+const EventEmitter = require("devtools/shared/event-emitter");
+
+const LERP_SPEED = 0.5;
+const ZOOM_SPEED = 0.01;
+const TRANSLATE_EPSILON = 1;
+const ZOOM_EPSILON = 0.001;
+const LINE_SCROLL_MODE = 1;
+const SCROLL_LINE_SIZE = 15;
+
+/**
+ * DragZoom is a constructor that contains the state of the current dragging and
+ * zooming behavior. It sets the scrolling and zooming behaviors.
+ *
+ * @param  {HTMLElement} container description
+ *         The container for the canvases
+ */
+function DragZoom(container, debounceRate, requestAnimationFrame) {
+  EventEmitter.decorate(this);
+
+  this.isDragging = false;
+
+  // The current mouse position
+  this.mouseX = container.offsetWidth / 2;
+  this.mouseY = container.offsetHeight / 2;
+
+  // The total size of the visualization after being zoomed, in pixels
+  this.zoomedWidth = container.offsetWidth;
+  this.zoomedHeight = container.offsetHeight;
+
+  // How much the visualization has been zoomed in
+  this.zoom = 0;
+
+  // The offset of visualization from the container. This is applied after
+  // the zoom, and the visualization by default is centered
+  this.translateX = 0;
+  this.translateY = 0;
+
+  // The size of the offset between the top/left of the container, and the
+  // top/left of the containing element. This value takes into account
+  // the devicePixelRatio for canvas draws.
+  this.offsetX = 0;
+  this.offsetY = 0;
+
+  // The smoothed values that are animated and eventually match the target
+  // values. The values are updated by the update loop
+  this.smoothZoom = 0;
+  this.smoothTranslateX = 0;
+  this.smoothTranslateY = 0;
+
+  // Add the constant values for testing purposes
+  this.ZOOM_SPEED = ZOOM_SPEED;
+  this.ZOOM_EPSILON = ZOOM_EPSILON;
+
+  let update = createUpdateLoop(container, this, requestAnimationFrame);
+
+  this.destroy = setHandlers(this, container, update, debounceRate);
+}
+
+module.exports = DragZoom;
+
+/**
+ * Returns an update loop. This loop smoothly updates the visualization when
+ * actions are performed. Once the animations have reached their target values
+ * the animation loop is stopped.
+ *
+ * Any value in the `dragZoom` object that starts with "smooth" is the
+ * smoothed version of a value that is interpolating toward the target value.
+ * For instance `dragZoom.smoothZoom` approaches `dragZoom.zoom` on each
+ * iteration of the update loop until it's sufficiently close as defined by
+ * the epsilon values.
+ *
+ * Only these smoothed values and the container CSS are updated by the loop.
+ *
+ * @param {HTMLDivElement} container
+ * @param {Object} dragZoom
+ *        The values that represent the current dragZoom state
+ * @param {Function} requestAnimationFrame
+ */
+function createUpdateLoop(container, dragZoom, requestAnimationFrame) {
+  let isLooping = false;
+
+  function update() {
+    let isScrollChanging = (
+      Math.abs(dragZoom.smoothZoom - dragZoom.zoom) > ZOOM_EPSILON
+    );
+    let isTranslateChanging = (
+      Math.abs(dragZoom.smoothTranslateX - dragZoom.translateX)
+      > TRANSLATE_EPSILON ||
+      Math.abs(dragZoom.smoothTranslateY - dragZoom.translateY)
+      > TRANSLATE_EPSILON
+    );
+
+    isLooping = isScrollChanging || isTranslateChanging;
+
+    if (isScrollChanging) {
+      dragZoom.smoothZoom = lerp(dragZoom.smoothZoom, dragZoom.zoom,
+                                 LERP_SPEED);
+    } else {
+      dragZoom.smoothZoom = dragZoom.zoom;
+    }
+
+    if (isTranslateChanging) {
+      dragZoom.smoothTranslateX = lerp(dragZoom.smoothTranslateX,
+                                       dragZoom.translateX, LERP_SPEED);
+      dragZoom.smoothTranslateY = lerp(dragZoom.smoothTranslateY,
+                                       dragZoom.translateY, LERP_SPEED);
+    } else {
+      dragZoom.smoothTranslateX = dragZoom.translateX;
+      dragZoom.smoothTranslateY = dragZoom.translateY;
+    }
+
+    let zoom = 1 + dragZoom.smoothZoom;
+    let x = dragZoom.smoothTranslateX;
+    let y = dragZoom.smoothTranslateY;
+    container.style.transform = `translate(${x}px, ${y}px) scale(${zoom})`;
+
+    if (isLooping) {
+      requestAnimationFrame(update);
+    }
+  }
+
+  // Go ahead and start the update loop
+  update();
+
+  return function restartLoopingIfStopped() {
+    if (!isLooping) {
+      update();
+    }
+  };
+}
+
+/**
+ * Set the various event listeners and return a function to remove them
+ *
+ * @param  {Object} dragZoom
+ * @param  {HTMLElement} container
+ * @param  {Function} update
+ * @return {Function}  The function to remove the handlers
+ */
+function setHandlers(dragZoom, container, update, debounceRate) {
+  let emitChanged = debounce(() => dragZoom.emit("change"), debounceRate);
+
+  let removeDragHandlers =
+    setDragHandlers(container, dragZoom, emitChanged, update);
+  let removeScrollHandlers =
+    setScrollHandlers(container, dragZoom, emitChanged, update);
+
+  return function removeHandlers() {
+    removeDragHandlers();
+    removeScrollHandlers();
+  };
+}
+
+/**
+ * Sets handlers for when the user drags on the canvas. It will update dragZoom
+ * object with new translate and offset values.
+ *
+ * @param  {HTMLElement} container
+ * @param  {Object} dragZoom
+ * @param  {Function} changed
+ * @param  {Function} update
+ */
+function setDragHandlers(container, dragZoom, emitChanged, update) {
+  let parentEl = container.parentElement;
+
+  function startDrag() {
+    dragZoom.isDragging = true;
+    container.style.cursor = "grabbing";
+  }
+
+  function stopDrag() {
+    dragZoom.isDragging = false;
+    container.style.cursor = "grab";
+  }
+
+  function drag(event) {
+    let prevMouseX = dragZoom.mouseX;
+    let prevMouseY = dragZoom.mouseY;
+
+    dragZoom.mouseX = event.clientX - parentEl.offsetLeft;
+    dragZoom.mouseY = event.clientY - parentEl.offsetTop;
+
+    if (!dragZoom.isDragging) {
+      return;
+    }
+
+    dragZoom.translateX += dragZoom.mouseX - prevMouseX;
+    dragZoom.translateY += dragZoom.mouseY - prevMouseY;
+
+    keepInView(container, dragZoom);
+
+    emitChanged();
+    update();
+  }
+
+  parentEl.addEventListener("mousedown", startDrag, false);
+  parentEl.addEventListener("mouseup", stopDrag, false);
+  parentEl.addEventListener("mouseout", stopDrag, false);
+  parentEl.addEventListener("mousemove", drag, false);
+
+  return function removeListeners() {
+    parentEl.removeEventListener("mousedown", startDrag, false);
+    parentEl.removeEventListener("mouseup", stopDrag, false);
+    parentEl.removeEventListener("mouseout", stopDrag, false);
+    parentEl.removeEventListener("mousemove", drag, false);
+  };
+}
+
+/**
+ * Sets the handlers for when the user scrolls. It updates the dragZoom object
+ * and keeps the canvases all within the view. After changing values update
+ * loop is called, and the changed event is emitted.
+ *
+ * @param  {HTMLDivElement} container
+ * @param  {Object} dragZoom
+ * @param  {Function} changed
+ * @param  {Function} update
+ */
+function setScrollHandlers(container, dragZoom, emitChanged, update) {
+  let window = container.ownerDocument.defaultView;
+
+  function handleWheel(event) {
+    event.preventDefault();
+
+    if (dragZoom.isDragging) {
+      return;
+    }
+
+    // Update the zoom level
+    let scrollDelta = getScrollDelta(event, window);
+    let prevZoom = dragZoom.zoom;
+    dragZoom.zoom = Math.max(0, dragZoom.zoom - scrollDelta * ZOOM_SPEED);
+    let deltaZoom = dragZoom.zoom - prevZoom;
+
+    // Calculate the updated width and height
+    let prevZoomedWidth = container.offsetWidth * (1 + prevZoom);
+    let prevZoomedHeight = container.offsetHeight * (1 + prevZoom);
+    dragZoom.zoomedWidth = container.offsetWidth * (1 + dragZoom.zoom);
+    dragZoom.zoomedHeight = container.offsetHeight * (1 + dragZoom.zoom);
+    let deltaWidth = dragZoom.zoomedWidth - prevZoomedWidth;
+    let deltaHeight = dragZoom.zoomedHeight - prevZoomedHeight;
+
+    let mouseOffsetX = dragZoom.mouseX - container.offsetWidth / 2;
+    let mouseOffsetY = dragZoom.mouseY - container.offsetHeight / 2;
+
+    // The ratio of where the center of the mouse is in regards to the total
+    // zoomed width/height
+    let ratioZoomX = (prevZoomedWidth / 2 + mouseOffsetX - dragZoom.translateX)
+      / prevZoomedWidth;
+    let ratioZoomY = (prevZoomedHeight / 2 + mouseOffsetY - dragZoom.translateY)
+      / prevZoomedHeight;
+
+    // Distribute the change in width and height based on the above ratio
+    dragZoom.translateX -= lerp(-deltaWidth / 2, deltaWidth / 2, ratioZoomX);
+    dragZoom.translateY -= lerp(-deltaHeight / 2, deltaHeight / 2, ratioZoomY);
+
+    // Keep the canvas in range of the container
+    keepInView(container, dragZoom);
+    emitChanged();
+    update();
+  }
+
+  container.addEventListener("wheel", handleWheel, false);
+
+  return function removeListener() {
+    container.removeEventListener("wheel", handleWheel, false);
+  };
+}
+
+/**
+ * Account for the various mouse wheel event types, per pixel or per line
+ *
+ * @param  {WheelEvent} event
+ * @param  {Window} window
+ * @return {Number} The scroll size in pixels
+ */
+function getScrollDelta(event, window) {
+  if (event.deltaMode === LINE_SCROLL_MODE) {
+    // Update by a fixed arbitrary value to normalize scroll types
+    return event.deltaY * SCROLL_LINE_SIZE;
+  }
+  return event.deltaY;
+}
+
+/**
+ * Keep the dragging and zooming within the view by updating the values in the
+ * `dragZoom` object.
+ *
+ * @param  {HTMLDivElement} container
+ * @param  {Object} dragZoom
+ */
+function keepInView(container, dragZoom) {
+  let { devicePixelRatio } = container.ownerDocument.defaultView;
+  let overdrawX = (dragZoom.zoomedWidth - container.offsetWidth) / 2;
+  let overdrawY = (dragZoom.zoomedHeight - container.offsetHeight) / 2;
+
+  dragZoom.translateX = Math.max(-overdrawX,
+                                 Math.min(overdrawX, dragZoom.translateX));
+  dragZoom.translateY = Math.max(-overdrawY,
+                                 Math.min(overdrawY, dragZoom.translateY));
+
+  dragZoom.offsetX = devicePixelRatio * (
+    (dragZoom.zoomedWidth - container.offsetWidth) / 2 - dragZoom.translateX
+  );
+  dragZoom.offsetY = devicePixelRatio * (
+    (dragZoom.zoomedHeight - container.offsetHeight) / 2 - dragZoom.translateY
+  );
+}