planning

node_modules/ol/src/easing.js

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+/**
+ * @module ol/easing
+ */
+
+/**
+ * Start slow and speed up.
+ * @param {number} t Input between 0 and 1.
+ * @return {number} Output between 0 and 1.
+ * @api
+ */
+export function easeIn(t) {
+  return Math.pow(t, 3);
+}
+
+/**
+ * Start fast and slow down.
+ * @param {number} t Input between 0 and 1.
+ * @return {number} Output between 0 and 1.
+ * @api
+ */
+export function easeOut(t) {
+  return 1 - easeIn(1 - t);
+}
+
+/**
+ * Start slow, speed up, and then slow down again.
+ * @param {number} t Input between 0 and 1.
+ * @return {number} Output between 0 and 1.
+ * @api
+ */
+export function inAndOut(t) {
+  return 3 * t * t - 2 * t * t * t;
+}
+
+/**
+ * Maintain a constant speed over time.
+ * @param {number} t Input between 0 and 1.
+ * @return {number} Output between 0 and 1.
+ * @api
+ */
+export function linear(t) {
+  return t;
+}
+
+/**
+ * Start slow, speed up, and at the very end slow down again.  This has the
+ * same general behavior as {@link module:ol/easing.inAndOut}, but the final
+ * slowdown is delayed.
+ * @param {number} t Input between 0 and 1.
+ * @return {number} Output between 0 and 1.
+ * @api
+ */
+export function upAndDown(t) {
+  if (t < 0.5) {
+    return inAndOut(2 * t);
+  } else {
+    return 1 - inAndOut(2 * (t - 0.5));
+  }
+}