Add existing to tracked

2026-08-11 09:53:42 -04:00
parent afe07f3055
commit ffd6e3d73c
8531 changed files with 4396230 additions and 0 deletions
@@ -0,0 +1,116 @@
+import defined from "../Core/defined.js";
+import Event from "../Core/Event.js";
+
+/**
+ * A {@link Property} whose value does not change with respect to simulation time.
+ *
+ * @alias ConstantProperty
+ * @constructor
+ *
+ * @param {*} [value] The property value.
+ *
+ * @see ConstantPositionProperty
+ */
+function ConstantProperty(value) {
+  this._value = undefined;
+  this._hasClone = false;
+  this._hasEquals = false;
+  this._definitionChanged = new Event();
+  this.setValue(value);
+}
+
+Object.defineProperties(ConstantProperty.prototype, {
+  /**
+   * Gets a value indicating if this property is constant.
+   * This property always returns <code>true</code>.
+   * @memberof ConstantProperty.prototype
+   *
+   * @type {boolean}
+   * @readonly
+   */
+  isConstant: {
+    value: true,
+  },
+  /**
+   * Gets the event that is raised whenever the definition of this property changes.
+   * The definition is changed whenever setValue is called with data different
+   * than the current value.
+   * @memberof ConstantProperty.prototype
+   *
+   * @type {Event}
+   * @readonly
+   */
+  definitionChanged: {
+    get: function () {
+      return this._definitionChanged;
+    },
+  },
+});
+
+/**
+ * Gets the value of the property.
+ *
+ * @param {JulianDate} [time] The time for which to retrieve the value.  This parameter is unused since the value does not change with respect to time.
+ * @param {object} [result] The object to store the value into, if omitted, a new instance is created and returned.
+ * @returns {object} The modified result parameter or a new instance if the result parameter was not supplied.
+ */
+ConstantProperty.prototype.getValue = function (time, result) {
+  return this._hasClone ? this._value.clone(result) : this._value;
+};
+
+/**
+ * Sets the value of the property.
+ *
+ * @param {*} value The property value.
+ */
+ConstantProperty.prototype.setValue = function (value) {
+  const oldValue = this._value;
+  if (oldValue !== value) {
+    const isDefined = defined(value);
+    const hasClone = isDefined && typeof value.clone === "function";
+    const hasEquals = isDefined && typeof value.equals === "function";
+
+    const changed = !hasEquals || !value.equals(oldValue);
+    if (changed) {
+      this._hasClone = hasClone;
+      this._hasEquals = hasEquals;
+      this._value = !hasClone ? value : value.clone(this._value);
+      this._definitionChanged.raiseEvent(this);
+    }
+  }
+};
+
+/**
+ * Compares this property to the provided property and returns
+ * <code>true</code> if they are equal, <code>false</code> otherwise.
+ *
+ * @param {Property} [other] The other property.
+ * @returns {boolean} <code>true</code> if left and right are equal, <code>false</code> otherwise.
+ */
+ConstantProperty.prototype.equals = function (other) {
+  return (
+    this === other || //
+    (other instanceof ConstantProperty && //
+      ((!this._hasEquals && this._value === other._value) || //
+        (this._hasEquals && this._value.equals(other._value))))
+  );
+};
+
+/**
+ * Gets this property's value.
+ *
+ * @returns {*} This property's value.
+ */
+ConstantProperty.prototype.valueOf = function () {
+  return this._value;
+};
+
+/**
+ * Creates a string representing this property's value.
+ *
+ * @returns {string} A string representing the property's value.
+ */
+ConstantProperty.prototype.toString = function () {
+  return String(this._value);
+};
+export default ConstantProperty;