jtBaseApp/node_modules/@cesium/widgets/Source/Animation/Animation.js

import {
  Color,
  defined,
  destroyObject,
  DeveloperError,
  getElement,
} from "@cesium/engine";
import subscribeAndEvaluate from "../subscribeAndEvaluate.js";

const svgNS = "http://www.w3.org/2000/svg";
const xlinkNS = "http://www.w3.org/1999/xlink";

let widgetForDrag;

const gradientEnabledColor0 = Color.fromCssColorString(
  "rgba(247,250,255,0.384)"
);
const gradientEnabledColor1 = Color.fromCssColorString(
  "rgba(143,191,255,0.216)"
);
const gradientEnabledColor2 = Color.fromCssColorString(
  "rgba(153,197,255,0.098)"
);
const gradientEnabledColor3 = Color.fromCssColorString(
  "rgba(255,255,255,0.086)"
);

const gradientDisabledColor0 = Color.fromCssColorString(
  "rgba(255,255,255,0.267)"
);
const gradientDisabledColor1 = Color.fromCssColorString("rgba(255,255,255,0)");

const gradientKnobColor = Color.fromCssColorString("rgba(66,67,68,0.3)");
const gradientPointerColor = Color.fromCssColorString("rgba(0,0,0,0.5)");

function getElementColor(element) {
  return Color.fromCssColorString(
    window.getComputedStyle(element).getPropertyValue("color")
  );
}

const svgIconsById = {
  animation_pathReset: {
    tagName: "path",
    transform: "translate(16,16) scale(0.85) translate(-16,-16)",
    d:
      "M24.316,5.318,9.833,13.682,9.833,5.5,5.5,5.5,5.5,25.5,9.833,25.5,9.833,17.318,24.316,25.682z",
  },
  animation_pathPause: {
    tagName: "path",
    transform: "translate(16,16) scale(0.85) translate(-16,-16)",
    d: "M13,5.5,7.5,5.5,7.5,25.5,13,25.5zM24.5,5.5,19,5.5,19,25.5,24.5,25.5z",
  },
  animation_pathPlay: {
    tagName: "path",
    transform: "translate(16,16) scale(0.85) translate(-16,-16)",
    d: "M6.684,25.682L24.316,15.5L6.684,5.318V25.682z",
  },
  animation_pathPlayReverse: {
    tagName: "path",
    transform: "translate(16,16) scale(-0.85,0.85) translate(-16,-16)",
    d: "M6.684,25.682L24.316,15.5L6.684,5.318V25.682z",
  },
  animation_pathLoop: {
    tagName: "path",
    transform: "translate(16,16) scale(0.85) translate(-16,-16)",
    d:
      "M24.249,15.499c-0.009,4.832-3.918,8.741-8.75,8.75c-2.515,0-4.768-1.064-6.365-2.763l2.068-1.442l-7.901-3.703l0.744,8.694l2.193-1.529c2.244,2.594,5.562,4.242,9.26,4.242c6.767,0,12.249-5.482,12.249-12.249H24.249zM15.499,6.75c2.516,0,4.769,1.065,6.367,2.764l-2.068,1.443l7.901,3.701l-0.746-8.693l-2.192,1.529c-2.245-2.594-5.562-4.245-9.262-4.245C8.734,3.25,3.25,8.734,3.249,15.499H6.75C6.758,10.668,10.668,6.758,15.499,6.75z",
  },
  animation_pathClock: {
    tagName: "path",
    transform: "translate(16,16) scale(0.85) translate(-16,-15.5)",
    d:
      "M15.5,2.374C8.251,2.375,2.376,8.251,2.374,15.5C2.376,22.748,8.251,28.623,15.5,28.627c7.249-0.004,13.124-5.879,13.125-13.127C28.624,8.251,22.749,2.375,15.5,2.374zM15.5,25.623C9.909,25.615,5.385,21.09,5.375,15.5C5.385,9.909,9.909,5.384,15.5,5.374c5.59,0.01,10.115,4.535,10.124,10.125C25.615,21.09,21.091,25.615,15.5,25.623zM8.625,15.5c-0.001-0.552-0.448-0.999-1.001-1c-0.553,0-1,0.448-1,1c0,0.553,0.449,1,1,1C8.176,16.5,8.624,16.053,8.625,15.5zM8.179,18.572c-0.478,0.277-0.642,0.889-0.365,1.367c0.275,0.479,0.889,0.641,1.365,0.365c0.479-0.275,0.643-0.887,0.367-1.367C9.27,18.461,8.658,18.297,8.179,18.572zM9.18,10.696c-0.479-0.276-1.09-0.112-1.366,0.366s-0.111,1.09,0.365,1.366c0.479,0.276,1.09,0.113,1.367-0.366C9.821,11.584,9.657,10.973,9.18,10.696zM22.822,12.428c0.478-0.275,0.643-0.888,0.366-1.366c-0.275-0.478-0.89-0.642-1.366-0.366c-0.479,0.278-0.642,0.89-0.366,1.367C21.732,12.54,22.344,12.705,22.822,12.428zM12.062,21.455c-0.478-0.275-1.089-0.111-1.366,0.367c-0.275,0.479-0.111,1.09,0.366,1.365c0.478,0.277,1.091,0.111,1.365-0.365C12.704,22.344,12.54,21.732,12.062,21.455zM12.062,9.545c0.479-0.276,0.642-0.888,0.366-1.366c-0.276-0.478-0.888-0.642-1.366-0.366s-0.642,0.888-0.366,1.366C10.973,9.658,11.584,9.822,12.062,9.545zM22.823,18.572c-0.48-0.275-1.092-0.111-1.367,0.365c-0.275,0.479-0.112,1.092,0.367,1.367c0.477,0.275,1.089,0.113,1.365-0.365C23.464,19.461,23.3,18.848,22.823,18.572zM19.938,7.813c-0.477-0.276-1.091-0.111-1.365,0.366c-0.275,0.48-0.111,1.091,0.366,1.367s1.089,0.112,1.366-0.366C20.581,8.702,20.418,8.089,19.938,7.813zM23.378,14.5c-0.554,0.002-1.001,0.45-1.001,1c0.001,0.552,0.448,1,1.001,1c0.551,0,1-0.447,1-1C24.378,14.949,23.929,14.5,23.378,14.5zM15.501,6.624c-0.552,0-1,0.448-1,1l-0.466,7.343l-3.004,1.96c-0.478,0.277-0.642,0.889-0.365,1.365c0.275,0.479,0.889,0.643,1.365,0.367l3.305-1.676C15.39,16.99,15.444,17,15.501,17c0.828,0,1.5-0.671,1.5-1.5l-0.5-7.876C16.501,7.072,16.053,6.624,15.501,6.624zM15.501,22.377c-0.552,0-1,0.447-1,1s0.448,1,1,1s1-0.447,1-1S16.053,22.377,15.501,22.377zM18.939,21.455c-0.479,0.277-0.643,0.889-0.366,1.367c0.275,0.477,0.888,0.643,1.366,0.365c0.478-0.275,0.642-0.889,0.366-1.365C20.028,21.344,19.417,21.18,18.939,21.455z",
  },
  animation_pathWingButton: {
    tagName: "path",
    d:
      "m 4.5,0.5 c -2.216,0 -4,1.784 -4,4 l 0,24 c 0,2.216 1.784,4 4,4 l 13.71875,0 C 22.478584,27.272785 27.273681,22.511272 32.5,18.25 l 0,-13.75 c 0,-2.216 -1.784,-4 -4,-4 l -24,0 z",
  },
  animation_pathPointer: {
    tagName: "path",
    d: "M-15,-65,-15,-55,15,-55,15,-65,0,-95z",
  },
  animation_pathSwooshFX: {
    tagName: "path",
    d:
      "m 85,0 c 0,16.617 -4.813944,35.356 -13.131081,48.4508 h 6.099803 c 8.317138,-13.0948 13.13322,-28.5955 13.13322,-45.2124 0,-46.94483 -38.402714,-85.00262 -85.7743869,-85.00262 -1.0218522,0 -2.0373001,0.0241 -3.0506131,0.0589 45.958443,1.59437 82.723058,35.77285 82.723058,81.70532 z",
  },
};

//Dynamically builds an SVG element from a JSON object.
function svgFromObject(obj) {
  const ele = document.createElementNS(svgNS, obj.tagName);
  for (const field in obj) {
    if (obj.hasOwnProperty(field) && field !== "tagName") {
      if (field === "children") {
        const len = obj.children.length;
        for (let i = 0; i < len; ++i) {
          ele.appendChild(svgFromObject(obj.children[i]));
        }
      } else if (field.indexOf("xlink:") === 0) {
        ele.setAttributeNS(xlinkNS, field.substring(6), obj[field]);
      } else if (field === "textContent") {
        ele.textContent = obj[field];
      } else {
        ele.setAttribute(field, obj[field]);
      }
    }
  }
  return ele;
}

function svgText(x, y, msg) {
  const text = document.createElementNS(svgNS, "text");
  text.setAttribute("x", x);
  text.setAttribute("y", y);
  text.setAttribute("class", "cesium-animation-svgText");

  const tspan = document.createElementNS(svgNS, "tspan");
  tspan.textContent = msg;
  text.appendChild(tspan);
  return text;
}

function setShuttleRingPointer(shuttleRingPointer, knobOuter, angle) {
  shuttleRingPointer.setAttribute(
    "transform",
    `translate(100,100) rotate(${angle})`
  );
  knobOuter.setAttribute("transform", `rotate(${angle})`);
}

const makeColorStringScratch = new Color();
function makeColorString(background, gradient) {
  const gradientAlpha = gradient.alpha;
  const backgroundAlpha = 1.0 - gradientAlpha;
  makeColorStringScratch.red =
    background.red * backgroundAlpha + gradient.red * gradientAlpha;
  makeColorStringScratch.green =
    background.green * backgroundAlpha + gradient.green * gradientAlpha;
  makeColorStringScratch.blue =
    background.blue * backgroundAlpha + gradient.blue * gradientAlpha;
  return makeColorStringScratch.toCssColorString();
}

function rectButton(x, y, path) {
  const iconInfo = svgIconsById[path];

  const button = {
    tagName: "g",
    class: "cesium-animation-rectButton",
    transform: `translate(${x},${y})`,
    children: [
      {
        tagName: "rect",
        class: "cesium-animation-buttonGlow",
        width: 32,
        height: 32,
        rx: 2,
        ry: 2,
      },
      {
        tagName: "rect",
        class: "cesium-animation-buttonMain",
        width: 32,
        height: 32,
        rx: 4,
        ry: 4,
      },
      {
        class: "cesium-animation-buttonPath",
        id: path,
        tagName: iconInfo.tagName,
        transform: iconInfo.transform,
        d: iconInfo.d,
      },
      {
        tagName: "title",
        textContent: "",
      },
    ],
  };
  return svgFromObject(button);
}

function wingButton(x, y, path) {
  const buttonIconInfo = svgIconsById[path];
  const wingIconInfo = svgIconsById["animation_pathWingButton"];

  const button = {
    tagName: "g",
    class: "cesium-animation-rectButton",
    transform: `translate(${x},${y})`,
    children: [
      {
        class: "cesium-animation-buttonGlow",
        id: "animation_pathWingButton",
        tagName: wingIconInfo.tagName,
        d: wingIconInfo.d,
      },
      {
        class: "cesium-animation-buttonMain",
        id: "animation_pathWingButton",
        tagName: wingIconInfo.tagName,
        d: wingIconInfo.d,
      },
      {
        class: "cesium-animation-buttonPath",
        id: path,
        tagName: buttonIconInfo.tagName,
        transform: buttonIconInfo.transform,
        d: buttonIconInfo.d,
      },
      {
        tagName: "title",
        textContent: "",
      },
    ],
  };
  return svgFromObject(button);
}

function setShuttleRingFromMouseOrTouch(widget, e) {
  const viewModel = widget._viewModel;
  const shuttleRingDragging = viewModel.shuttleRingDragging;

  if (shuttleRingDragging && widgetForDrag !== widget) {
    return;
  }

  if (
    e.type === "mousedown" ||
    (shuttleRingDragging && e.type === "mousemove") ||
    (e.type === "touchstart" && e.touches.length === 1) ||
    (shuttleRingDragging && e.type === "touchmove" && e.touches.length === 1)
  ) {
    const centerX = widget._centerX;
    const centerY = widget._centerY;
    const svg = widget._svgNode;
    const rect = svg.getBoundingClientRect();
    let clientX;
    let clientY;
    if (e.type === "touchstart" || e.type === "touchmove") {
      clientX = e.touches[0].clientX;
      clientY = e.touches[0].clientY;
    } else {
      clientX = e.clientX;
      clientY = e.clientY;
    }

    if (
      !shuttleRingDragging &&
      (clientX > rect.right ||
        clientX < rect.left ||
        clientY < rect.top ||
        clientY > rect.bottom)
    ) {
      return;
    }

    const pointerRect = widget._shuttleRingPointer.getBoundingClientRect();

    const x = clientX - centerX - rect.left;
    const y = clientY - centerY - rect.top;

    let angle = (Math.atan2(y, x) * 180) / Math.PI + 90;
    if (angle > 180) {
      angle -= 360;
    }
    const shuttleRingAngle = viewModel.shuttleRingAngle;
    if (
      shuttleRingDragging ||
      (clientX < pointerRect.right &&
        clientX > pointerRect.left &&
        clientY > pointerRect.top &&
        clientY < pointerRect.bottom)
    ) {
      widgetForDrag = widget;
      viewModel.shuttleRingDragging = true;
      viewModel.shuttleRingAngle = angle;
    } else if (angle < shuttleRingAngle) {
      viewModel.slower();
    } else if (angle > shuttleRingAngle) {
      viewModel.faster();
    }
    e.preventDefault();
  } else {
    if (widget === widgetForDrag) {
      widgetForDrag = undefined;
    }
    viewModel.shuttleRingDragging = false;
  }
}

//This is a private class for treating an SVG element like a button.
//If we ever need a general purpose SVG button, we can make this generic.
function SvgButton(svgElement, viewModel) {
  this._viewModel = viewModel;
  this.svgElement = svgElement;
  this._enabled = undefined;
  this._toggled = undefined;

  const that = this;
  this._clickFunction = function () {
    const command = that._viewModel.command;
    if (command.canExecute) {
      command();
    }
  };

  svgElement.addEventListener("click", this._clickFunction, true);

  //TODO: Since the animation widget uses SVG and has no HTML backing,
  //we need to wire everything up manually.  Knockout can supposedly
  //bind to SVG, so we we figure that out we can modify our SVG
  //to include the binding information directly.

  this._subscriptions = [
    //
    subscribeAndEvaluate(viewModel, "toggled", this.setToggled, this), //
    subscribeAndEvaluate(viewModel, "tooltip", this.setTooltip, this), //
    subscribeAndEvaluate(
      viewModel.command,
      "canExecute",
      this.setEnabled,
      this
    ),
  ];
}

SvgButton.prototype.destroy = function () {
  this.svgElement.removeEventListener("click", this._clickFunction, true);
  const subscriptions = this._subscriptions;
  for (let i = 0, len = subscriptions.length; i < len; i++) {
    subscriptions[i].dispose();
  }
  destroyObject(this);
};

SvgButton.prototype.isDestroyed = function () {
  return false;
};

SvgButton.prototype.setEnabled = function (enabled) {
  if (this._enabled !== enabled) {
    this._enabled = enabled;

    if (!enabled) {
      this.svgElement.setAttribute("class", "cesium-animation-buttonDisabled");
      return;
    }

    if (this._toggled) {
      this.svgElement.setAttribute(
        "class",
        "cesium-animation-rectButton cesium-animation-buttonToggled"
      );
      return;
    }

    this.svgElement.setAttribute("class", "cesium-animation-rectButton");
  }
};

SvgButton.prototype.setToggled = function (toggled) {
  if (this._toggled !== toggled) {
    this._toggled = toggled;

    if (this._enabled) {
      if (toggled) {
        this.svgElement.setAttribute(
          "class",
          "cesium-animation-rectButton cesium-animation-buttonToggled"
        );
      } else {
        this.svgElement.setAttribute("class", "cesium-animation-rectButton");
      }
    }
  }
};

SvgButton.prototype.setTooltip = function (tooltip) {
  this.svgElement.getElementsByTagName("title")[0].textContent = tooltip;
};

/**
 * <span style="display: block; text-align: center;">
 * <img src="Images/AnimationWidget.png" width="211" height="142" alt="" />
 * <br />Animation widget
 * </span>
 * <br /><br />
 * The Animation widget provides buttons for play, pause, and reverse, along with the
 * current time and date, surrounded by a "shuttle ring" for controlling the speed of animation.
 * <br /><br />
 * The "shuttle ring" concept is borrowed from video editing, where typically a
 * "jog wheel" can be rotated to move past individual animation frames very slowly, and
 * a surrounding shuttle ring can be twisted to control direction and speed of fast playback.
 * Cesium typically treats time as continuous (not broken into pre-defined animation frames),
 * so this widget offers no jog wheel.  Instead, the shuttle ring is capable of both fast and
 * very slow playback.  Click and drag the shuttle ring pointer itself (shown above in green),
 * or click in the rest of the ring area to nudge the pointer to the next preset speed in that direction.
 * <br /><br />
 * The Animation widget also provides a "realtime" button (in the upper-left) that keeps
 * animation time in sync with the end user's system clock, typically displaying
 * "today" or "right now."  This mode is not available in {@link ClockRange.CLAMPED} or
 * {@link ClockRange.LOOP_STOP} mode if the current time is outside of {@link Clock}'s startTime and endTime.
 *
 * @alias Animation
 * @constructor
 *
 * @param {Element|string} container The DOM element or ID that will contain the widget.
 * @param {AnimationViewModel} viewModel The view model used by this widget.
 *
 * @exception {DeveloperError} Element with id "container" does not exist in the document.
 *
 *
 * @example
 * // In HTML head, include a link to Animation.css stylesheet,
 * // and in the body, include: <div id="animationContainer"></div>
 *
 * const clock = new Cesium.Clock();
 * const clockViewModel = new Cesium.ClockViewModel(clock);
 * const viewModel = new Cesium.AnimationViewModel(clockViewModel);
 * const widget = new Cesium.Animation('animationContainer', viewModel);
 *
 * function tick() {
 *     clock.tick();
 *     requestAnimationFrame(tick);
 * }
 * requestAnimationFrame(tick);
 *
 * @see AnimationViewModel
 * @see Clock
 */
function Animation(container, viewModel) {
  //>>includeStart('debug', pragmas.debug);
  if (!defined(container)) {
    throw new DeveloperError("container is required.");
  }
  if (!defined(viewModel)) {
    throw new DeveloperError("viewModel is required.");
  }
  //>>includeEnd('debug');

  container = getElement(container);
  this._viewModel = viewModel;
  this._container = container;
  this._centerX = 0;
  this._centerY = 0;
  this._defsElement = undefined;
  this._svgNode = undefined;
  this._topG = undefined;
  this._lastHeight = undefined;
  this._lastWidth = undefined;

  const ownerDocument = container.ownerDocument;

  // Firefox requires SVG references to be included directly, not imported from external CSS.
  // Also, CSS minifiers get confused by this being in an external CSS file.
  const cssStyle = document.createElement("style");
  cssStyle.textContent =
    ".cesium-animation-rectButton .cesium-animation-buttonGlow { filter: url(#animation_blurred); }\
.cesium-animation-rectButton .cesium-animation-buttonMain { fill: url(#animation_buttonNormal); }\
.cesium-animation-buttonToggled .cesium-animation-buttonMain { fill: url(#animation_buttonToggled); }\
.cesium-animation-rectButton:hover .cesium-animation-buttonMain { fill: url(#animation_buttonHovered); }\
.cesium-animation-buttonDisabled .cesium-animation-buttonMain { fill: url(#animation_buttonDisabled); }\
.cesium-animation-shuttleRingG .cesium-animation-shuttleRingSwoosh { fill: url(#animation_shuttleRingSwooshGradient); }\
.cesium-animation-shuttleRingG:hover .cesium-animation-shuttleRingSwoosh { fill: url(#animation_shuttleRingSwooshHovered); }\
.cesium-animation-shuttleRingPointer { fill: url(#animation_shuttleRingPointerGradient); }\
.cesium-animation-shuttleRingPausePointer { fill: url(#animation_shuttleRingPointerPaused); }\
.cesium-animation-knobOuter { fill: url(#animation_knobOuter); }\
.cesium-animation-knobInner { fill: url(#animation_knobInner); }";

  ownerDocument.head.insertBefore(cssStyle, ownerDocument.head.childNodes[0]);

  const themeEle = document.createElement("div");
  themeEle.className = "cesium-animation-theme";
  themeEle.innerHTML =
    '<div class="cesium-animation-themeNormal"></div>\
<div class="cesium-animation-themeHover"></div>\
<div class="cesium-animation-themeSelect"></div>\
<div class="cesium-animation-themeDisabled"></div>\
<div class="cesium-animation-themeKnob"></div>\
<div class="cesium-animation-themePointer"></div>\
<div class="cesium-animation-themeSwoosh"></div>\
<div class="cesium-animation-themeSwooshHover"></div>';

  this._theme = themeEle;
  this._themeNormal = themeEle.childNodes[0];
  this._themeHover = themeEle.childNodes[1];
  this._themeSelect = themeEle.childNodes[2];
  this._themeDisabled = themeEle.childNodes[3];
  this._themeKnob = themeEle.childNodes[4];
  this._themePointer = themeEle.childNodes[5];
  this._themeSwoosh = themeEle.childNodes[6];
  this._themeSwooshHover = themeEle.childNodes[7];

  const svg = document.createElementNS(svgNS, "svg:svg");
  this._svgNode = svg;

  // Define the XLink namespace that SVG uses
  svg.setAttributeNS("http://www.w3.org/2000/xmlns/", "xmlns:xlink", xlinkNS);

  const topG = document.createElementNS(svgNS, "g");
  this._topG = topG;

  this._realtimeSVG = new SvgButton(
    wingButton(3, 4, "animation_pathClock"),
    viewModel.playRealtimeViewModel
  );
  this._playReverseSVG = new SvgButton(
    rectButton(44, 99, "animation_pathPlayReverse"),
    viewModel.playReverseViewModel
  );
  this._playForwardSVG = new SvgButton(
    rectButton(124, 99, "animation_pathPlay"),
    viewModel.playForwardViewModel
  );
  this._pauseSVG = new SvgButton(
    rectButton(84, 99, "animation_pathPause"),
    viewModel.pauseViewModel
  );

  const buttonsG = document.createElementNS(svgNS, "g");
  buttonsG.appendChild(this._realtimeSVG.svgElement);
  buttonsG.appendChild(this._playReverseSVG.svgElement);
  buttonsG.appendChild(this._playForwardSVG.svgElement);
  buttonsG.appendChild(this._pauseSVG.svgElement);

  const shuttleRingBackPanel = svgFromObject({
    tagName: "circle",
    class: "cesium-animation-shuttleRingBack",
    cx: 100,
    cy: 100,
    r: 99,
  });
  this._shuttleRingBackPanel = shuttleRingBackPanel;

  const swooshIconInfo = svgIconsById["animation_pathSwooshFX"];
  const shuttleRingPointerIconInfo = svgIconsById["animation_pathPointer"];

  const shuttleRingSwooshG = svgFromObject({
    tagName: "g",
    class: "cesium-animation-shuttleRingSwoosh",
    children: [
      {
        tagName: swooshIconInfo.tagName,
        transform: "translate(100,97) scale(-1,1)",
        id: "animation_pathSwooshFX",
        d: swooshIconInfo.d,
      },
      {
        tagName: swooshIconInfo.tagName,
        transform: "translate(100,97)",
        id: "animation_pathSwooshFX",
        d: swooshIconInfo.d,
      },
      {
        tagName: "line",
        x1: 100,
        y1: 8,
        x2: 100,
        y2: 22,
      },
    ],
  });
  this._shuttleRingSwooshG = shuttleRingSwooshG;

  this._shuttleRingPointer = svgFromObject({
    class: "cesium-animation-shuttleRingPointer",
    id: "animation_pathPointer",
    tagName: shuttleRingPointerIconInfo.tagName,
    d: shuttleRingPointerIconInfo.d,
  });

  const knobG = svgFromObject({
    tagName: "g",
    transform: "translate(100,100)",
  });

  this._knobOuter = svgFromObject({
    tagName: "circle",
    class: "cesium-animation-knobOuter",
    cx: 0,
    cy: 0,
    r: 71,
  });

  const knobInnerAndShieldSize = 61;

  const knobInner = svgFromObject({
    tagName: "circle",
    class: "cesium-animation-knobInner",
    cx: 0,
    cy: 0,
    r: knobInnerAndShieldSize,
  });

  this._knobDate = svgText(0, -24, "");
  this._knobTime = svgText(0, -7, "");
  this._knobStatus = svgText(0, -41, "");

  // widget shield catches clicks on the knob itself (even while DOM elements underneath are changing).
  const knobShield = svgFromObject({
    tagName: "circle",
    class: "cesium-animation-blank",
    cx: 0,
    cy: 0,
    r: knobInnerAndShieldSize,
  });

  const shuttleRingBackG = document.createElementNS(svgNS, "g");
  shuttleRingBackG.setAttribute("class", "cesium-animation-shuttleRingG");

  container.appendChild(themeEle);
  topG.appendChild(shuttleRingBackG);
  topG.appendChild(knobG);
  topG.appendChild(buttonsG);

  shuttleRingBackG.appendChild(shuttleRingBackPanel);
  shuttleRingBackG.appendChild(shuttleRingSwooshG);
  shuttleRingBackG.appendChild(this._shuttleRingPointer);

  knobG.appendChild(this._knobOuter);
  knobG.appendChild(knobInner);
  knobG.appendChild(this._knobDate);
  knobG.appendChild(this._knobTime);
  knobG.appendChild(this._knobStatus);
  knobG.appendChild(knobShield);

  svg.appendChild(topG);
  container.appendChild(svg);

  const that = this;
  function mouseCallback(e) {
    setShuttleRingFromMouseOrTouch(that, e);
  }
  this._mouseCallback = mouseCallback;

  shuttleRingBackPanel.addEventListener("mousedown", mouseCallback, true);
  shuttleRingBackPanel.addEventListener("touchstart", mouseCallback, true);
  shuttleRingSwooshG.addEventListener("mousedown", mouseCallback, true);
  shuttleRingSwooshG.addEventListener("touchstart", mouseCallback, true);
  ownerDocument.addEventListener("mousemove", mouseCallback, true);
  ownerDocument.addEventListener("touchmove", mouseCallback, true);
  ownerDocument.addEventListener("mouseup", mouseCallback, true);
  ownerDocument.addEventListener("touchend", mouseCallback, true);
  ownerDocument.addEventListener("touchcancel", mouseCallback, true);
  this._shuttleRingPointer.addEventListener("mousedown", mouseCallback, true);
  this._shuttleRingPointer.addEventListener("touchstart", mouseCallback, true);
  this._knobOuter.addEventListener("mousedown", mouseCallback, true);
  this._knobOuter.addEventListener("touchstart", mouseCallback, true);

  //TODO: Since the animation widget uses SVG and has no HTML backing,
  //we need to wire everything up manually.  Knockout can supposedly
  //bind to SVG, so we we figure that out we can modify our SVG
  //to include the binding information directly.

  const timeNode = this._knobTime.childNodes[0];
  const dateNode = this._knobDate.childNodes[0];
  const statusNode = this._knobStatus.childNodes[0];
  let isPaused;
  this._subscriptions = [
    //
    subscribeAndEvaluate(viewModel.pauseViewModel, "toggled", function (value) {
      if (isPaused !== value) {
        isPaused = value;
        if (isPaused) {
          that._shuttleRingPointer.setAttribute(
            "class",
            "cesium-animation-shuttleRingPausePointer"
          );
        } else {
          that._shuttleRingPointer.setAttribute(
            "class",
            "cesium-animation-shuttleRingPointer"
          );
        }
      }
    }),

    subscribeAndEvaluate(viewModel, "shuttleRingAngle", function (value) {
      setShuttleRingPointer(that._shuttleRingPointer, that._knobOuter, value);
    }),

    subscribeAndEvaluate(viewModel, "dateLabel", function (value) {
      if (dateNode.textContent !== value) {
        dateNode.textContent = value;
      }
    }),

    subscribeAndEvaluate(viewModel, "timeLabel", function (value) {
      if (timeNode.textContent !== value) {
        timeNode.textContent = value;
      }
    }),

    subscribeAndEvaluate(viewModel, "multiplierLabel", function (value) {
      if (statusNode.textContent !== value) {
        statusNode.textContent = value;
      }
    }),
  ];

  this.applyThemeChanges();
  this.resize();
}

Object.defineProperties(Animation.prototype, {
  /**
   * Gets the parent container.
   *
   * @memberof Animation.prototype
   * @type {Element}
   * @readonly
   */
  container: {
    get: function () {
      return this._container;
    },
  },

  /**
   * Gets the view model.
   *
   * @memberof Animation.prototype
   * @type {AnimationViewModel}
   * @readonly
   */
  viewModel: {
    get: function () {
      return this._viewModel;
    },
  },
});

/**
 * @returns {boolean} true if the object has been destroyed, false otherwise.
 */
Animation.prototype.isDestroyed = function () {
  return false;
};

/**
 * Destroys the animation widget.  Should be called if permanently
 * removing the widget from layout.
 */
Animation.prototype.destroy = function () {
  if (defined(this._observer)) {
    this._observer.disconnect();
    this._observer = undefined;
  }

  const doc = this._container.ownerDocument;

  const mouseCallback = this._mouseCallback;
  this._shuttleRingBackPanel.removeEventListener(
    "mousedown",
    mouseCallback,
    true
  );
  this._shuttleRingBackPanel.removeEventListener(
    "touchstart",
    mouseCallback,
    true
  );
  this._shuttleRingSwooshG.removeEventListener(
    "mousedown",
    mouseCallback,
    true
  );
  this._shuttleRingSwooshG.removeEventListener(
    "touchstart",
    mouseCallback,
    true
  );
  doc.removeEventListener("mousemove", mouseCallback, true);
  doc.removeEventListener("touchmove", mouseCallback, true);
  doc.removeEventListener("mouseup", mouseCallback, true);
  doc.removeEventListener("touchend", mouseCallback, true);
  doc.removeEventListener("touchcancel", mouseCallback, true);
  this._shuttleRingPointer.removeEventListener(
    "mousedown",
    mouseCallback,
    true
  );
  this._shuttleRingPointer.removeEventListener(
    "touchstart",
    mouseCallback,
    true
  );
  this._knobOuter.removeEventListener("mousedown", mouseCallback, true);
  this._knobOuter.removeEventListener("touchstart", mouseCallback, true);

  this._container.removeChild(this._svgNode);
  this._container.removeChild(this._theme);
  this._realtimeSVG.destroy();
  this._playReverseSVG.destroy();
  this._playForwardSVG.destroy();
  this._pauseSVG.destroy();

  const subscriptions = this._subscriptions;
  for (let i = 0, len = subscriptions.length; i < len; i++) {
    subscriptions[i].dispose();
  }

  return destroyObject(this);
};

/**
 * Resizes the widget to match the container size.
 * This function should be called whenever the container size is changed.
 */
Animation.prototype.resize = function () {
  const parentWidth = this._container.clientWidth;
  const parentHeight = this._container.clientHeight;
  if (parentWidth === this._lastWidth && parentHeight === this._lastHeight) {
    return;
  }

  const svg = this._svgNode;

  //The width and height as the SVG was originally drawn.
  const baseWidth = 200;
  const baseHeight = 132;

  let width = parentWidth;
  let height = parentHeight;

  if (parentWidth === 0 && parentHeight === 0) {
    width = baseWidth;
    height = baseHeight;
  } else if (parentWidth === 0) {
    height = parentHeight;
    width = baseWidth * (parentHeight / baseHeight);
  } else if (parentHeight === 0) {
    width = parentWidth;
    height = baseHeight * (parentWidth / baseWidth);
  }

  const scaleX = width / baseWidth;
  const scaleY = height / baseHeight;

  svg.style.cssText = `width: ${width}px; height: ${height}px; position: absolute; bottom: 0; left: 0; overflow: hidden;`;
  svg.setAttribute("width", width);
  svg.setAttribute("height", height);
  svg.setAttribute("viewBox", `0 0 ${width} ${height}`);

  this._topG.setAttribute("transform", `scale(${scaleX},${scaleY})`);

  this._centerX = Math.max(1, 100.0 * scaleX);
  this._centerY = Math.max(1, 100.0 * scaleY);

  this._lastHeight = parentWidth;
  this._lastWidth = parentHeight;
};

/**
 * Updates the widget to reflect any modified CSS rules for theming.
 *
 * @example
 * //Switch to the cesium-lighter theme.
 * document.body.className = 'cesium-lighter';
 * animation.applyThemeChanges();
 */
Animation.prototype.applyThemeChanges = function () {
  // Since we rely on computed styles for themeing, we can't actually
  // do anything if the container has not yet been added to the DOM.
  // Set up an observer to be notified when it is added and apply
  // the changes at that time.

  const doc = this._container.ownerDocument;

  if (!doc.body.contains(this._container)) {
    if (defined(this._observer)) {
      //Already listening.
      return;
    }
    const that = this;
    that._observer = new MutationObserver(function () {
      if (doc.body.contains(that._container)) {
        that._observer.disconnect();
        that._observer = undefined;
        that.applyThemeChanges();
      }
    });
    that._observer.observe(doc, { childList: true, subtree: true });
    return;
  }

  const buttonNormalBackColor = getElementColor(this._themeNormal);
  const buttonHoverBackColor = getElementColor(this._themeHover);
  const buttonToggledBackColor = getElementColor(this._themeSelect);
  const buttonDisabledBackColor = getElementColor(this._themeDisabled);
  const knobBackColor = getElementColor(this._themeKnob);
  const pointerColor = getElementColor(this._themePointer);
  const swooshColor = getElementColor(this._themeSwoosh);
  const swooshHoverColor = getElementColor(this._themeSwooshHover);

  const defsElement = svgFromObject({
    tagName: "defs",
    children: [
      {
        id: "animation_buttonNormal",
        tagName: "linearGradient",
        x1: "50%",
        y1: "0%",
        x2: "50%",
        y2: "100%",
        children: [
          //add a 'stop-opacity' field to make translucent.
          {
            tagName: "stop",
            offset: "0%",
            "stop-color": makeColorString(
              buttonNormalBackColor,
              gradientEnabledColor0
            ),
          },
          {
            tagName: "stop",
            offset: "12%",
            "stop-color": makeColorString(
              buttonNormalBackColor,
              gradientEnabledColor1
            ),
          },
          {
            tagName: "stop",
            offset: "46%",
            "stop-color": makeColorString(
              buttonNormalBackColor,
              gradientEnabledColor2
            ),
          },
          {
            tagName: "stop",
            offset: "81%",
            "stop-color": makeColorString(
              buttonNormalBackColor,
              gradientEnabledColor3
            ),
          },
        ],
      },
      {
        id: "animation_buttonHovered",
        tagName: "linearGradient",
        x1: "50%",
        y1: "0%",
        x2: "50%",
        y2: "100%",
        children: [
          {
            tagName: "stop",
            offset: "0%",
            "stop-color": makeColorString(
              buttonHoverBackColor,
              gradientEnabledColor0
            ),
          },
          {
            tagName: "stop",
            offset: "12%",
            "stop-color": makeColorString(
              buttonHoverBackColor,
              gradientEnabledColor1
            ),
          },
          {
            tagName: "stop",
            offset: "46%",
            "stop-color": makeColorString(
              buttonHoverBackColor,
              gradientEnabledColor2
            ),
          },
          {
            tagName: "stop",
            offset: "81%",
            "stop-color": makeColorString(
              buttonHoverBackColor,
              gradientEnabledColor3
            ),
          },
        ],
      },
      {
        id: "animation_buttonToggled",
        tagName: "linearGradient",
        x1: "50%",
        y1: "0%",
        x2: "50%",
        y2: "100%",
        children: [
          {
            tagName: "stop",
            offset: "0%",
            "stop-color": makeColorString(
              buttonToggledBackColor,
              gradientEnabledColor0
            ),
          },
          {
            tagName: "stop",
            offset: "12%",
            "stop-color": makeColorString(
              buttonToggledBackColor,
              gradientEnabledColor1
            ),
          },
          {
            tagName: "stop",
            offset: "46%",
            "stop-color": makeColorString(
              buttonToggledBackColor,
              gradientEnabledColor2
            ),
          },
          {
            tagName: "stop",
            offset: "81%",
            "stop-color": makeColorString(
              buttonToggledBackColor,
              gradientEnabledColor3
            ),
          },
        ],
      },
      {
        id: "animation_buttonDisabled",
        tagName: "linearGradient",
        x1: "50%",
        y1: "0%",
        x2: "50%",
        y2: "100%",
        children: [
          {
            tagName: "stop",
            offset: "0%",
            "stop-color": makeColorString(
              buttonDisabledBackColor,
              gradientDisabledColor0
            ),
          },
          {
            tagName: "stop",
            offset: "75%",
            "stop-color": makeColorString(
              buttonDisabledBackColor,
              gradientDisabledColor1
            ),
          },
        ],
      },
      {
        id: "animation_blurred",
        tagName: "filter",
        width: "200%",
        height: "200%",
        x: "-50%",
        y: "-50%",
        children: [
          {
            tagName: "feGaussianBlur",
            stdDeviation: 4,
            in: "SourceGraphic",
          },
        ],
      },
      {
        id: "animation_shuttleRingSwooshGradient",
        tagName: "linearGradient",
        x1: "50%",
        y1: "0%",
        x2: "50%",
        y2: "100%",
        children: [
          {
            tagName: "stop",
            offset: "0%",
            "stop-opacity": 0.2,
            "stop-color": swooshColor.toCssColorString(),
          },
          {
            tagName: "stop",
            offset: "85%",
            "stop-opacity": 0.85,
            "stop-color": swooshColor.toCssColorString(),
          },
          {
            tagName: "stop",
            offset: "95%",
            "stop-opacity": 0.05,
            "stop-color": swooshColor.toCssColorString(),
          },
        ],
      },
      {
        id: "animation_shuttleRingSwooshHovered",
        tagName: "linearGradient",
        x1: "50%",
        y1: "0%",
        x2: "50%",
        y2: "100%",
        children: [
          {
            tagName: "stop",
            offset: "0%",
            "stop-opacity": 0.2,
            "stop-color": swooshHoverColor.toCssColorString(),
          },
          {
            tagName: "stop",
            offset: "85%",
            "stop-opacity": 0.85,
            "stop-color": swooshHoverColor.toCssColorString(),
          },
          {
            tagName: "stop",
            offset: "95%",
            "stop-opacity": 0.05,
            "stop-color": swooshHoverColor.toCssColorString(),
          },
        ],
      },
      {
        id: "animation_shuttleRingPointerGradient",
        tagName: "linearGradient",
        x1: "0%",
        y1: "50%",
        x2: "100%",
        y2: "50%",
        children: [
          {
            tagName: "stop",
            offset: "0%",
            "stop-color": pointerColor.toCssColorString(),
          },
          {
            tagName: "stop",
            offset: "40%",
            "stop-color": pointerColor.toCssColorString(),
          },
          {
            tagName: "stop",
            offset: "60%",
            "stop-color": makeColorString(pointerColor, gradientPointerColor),
          },
          {
            tagName: "stop",
            offset: "100%",
            "stop-color": makeColorString(pointerColor, gradientPointerColor),
          },
        ],
      },
      {
        id: "animation_shuttleRingPointerPaused",
        tagName: "linearGradient",
        x1: "0%",
        y1: "50%",
        x2: "100%",
        y2: "50%",
        children: [
          {
            tagName: "stop",
            offset: "0%",
            "stop-color": "#CCC",
          },
          {
            tagName: "stop",
            offset: "40%",
            "stop-color": "#CCC",
          },
          {
            tagName: "stop",
            offset: "60%",
            "stop-color": "#555",
          },
          {
            tagName: "stop",
            offset: "100%",
            "stop-color": "#555",
          },
        ],
      },
      {
        id: "animation_knobOuter",
        tagName: "linearGradient",
        x1: "20%",
        y1: "0%",
        x2: "90%",
        y2: "100%",
        children: [
          {
            tagName: "stop",
            offset: "5%",
            "stop-color": makeColorString(knobBackColor, gradientEnabledColor0),
          },
          {
            tagName: "stop",
            offset: "60%",
            "stop-color": makeColorString(knobBackColor, gradientKnobColor),
          },
          {
            tagName: "stop",
            offset: "85%",
            "stop-color": makeColorString(knobBackColor, gradientEnabledColor1),
          },
        ],
      },
      {
        id: "animation_knobInner",
        tagName: "linearGradient",
        x1: "20%",
        y1: "0%",
        x2: "90%",
        y2: "100%",
        children: [
          {
            tagName: "stop",
            offset: "5%",
            "stop-color": makeColorString(knobBackColor, gradientKnobColor),
          },
          {
            tagName: "stop",
            offset: "60%",
            "stop-color": makeColorString(knobBackColor, gradientEnabledColor0),
          },
          {
            tagName: "stop",
            offset: "85%",
            "stop-color": makeColorString(knobBackColor, gradientEnabledColor3),
          },
        ],
      },
    ],
  });

  if (!defined(this._defsElement)) {
    this._svgNode.appendChild(defsElement);
  } else {
    this._svgNode.replaceChild(defsElement, this._defsElement);
  }
  this._defsElement = defsElement;
};
export default Animation;