From 92f91816b9a8040f02107df21daaa3d4f558b627 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rodrigo=20Gir=C3=A3o=20Serr=C3=A3o?=
 <rodrigogiraoserrao@gmail.com>
Date: Sat, 4 Sep 2021 22:47:45 +0100
Subject: [PATCH] Add script that generates test data for easings.

---
 tools/gen_easings_tests.ts | 233 +++++++++++++++++++++++++++++++++++++
 1 file changed, 233 insertions(+)
 create mode 100644 tools/gen_easings_tests.ts

diff --git a/tools/gen_easings_tests.ts b/tools/gen_easings_tests.ts
new file mode 100644
index 000000000..ceb5de02a
--- /dev/null
+++ b/tools/gen_easings_tests.ts
@@ -0,0 +1,233 @@
+/*
+ * Easing functions from http://easings.net;
+ * This script generates the data points used to test the _easing.py functions.
+ */
+
+function easeInSine(x: number): number {
+    return 1 - cos((x * PI) / 2);
+}
+
+function easeOutSine(x: number): number {
+    return sin((x * PI) / 2);
+}
+
+function easeInOutSine(x: number): number {
+    return -(cos(PI * x) - 1) / 2;
+}
+
+
+function easeInQuad(x: number): number {
+    return x * x;
+}
+
+function easeOutQuad(x: number): number {
+    return 1 - (1 - x) * (1 - x);
+}
+
+function easeInOutQuad(x: number): number {
+    return x < 0.5 ? 2 * x * x : 1 - pow(-2 * x + 2, 2) / 2;
+}
+
+
+function easeInCubic(x: number): number {
+    return x * x * x;
+}
+
+function easeOutCubic(x: number): number {
+    return 1 - pow(1 - x, 3);
+}
+
+function easeInOutCubic(x: number): number {
+    return x < 0.5 ? 4 * x * x * x : 1 - pow(-2 * x + 2, 3) / 2;
+}
+
+
+function easeInQuart(x: number): number {
+    return x * x * x * x;
+}
+
+function easeOutQuart(x: number): number {
+    return 1 - pow(1 - x, 4);
+}
+
+function easeInOutQuart(x: number): number {
+    return x < 0.5 ? 8 * x * x * x * x : 1 - pow(-2 * x + 2, 4) / 2;
+}
+
+
+function easeInQuint(x: number): number {
+    return x * x * x * x * x;
+}
+
+function easeOutQuint(x: number): number {
+    return 1 - pow(1 - x, 5);
+}
+
+function easeInOutQuint(x: number): number {
+    return x < 0.5 ? 16 * x * x * x * x * x : 1 - pow(-2 * x + 2, 5) / 2;
+}
+
+
+function easeInExpo(x: number): number {
+    return x === 0 ? 0 : pow(2, 10 * x - 10);
+}
+
+function easeOutExpo(x: number): number {
+    return x === 1 ? 1 : 1 - pow(2, -10 * x);
+}
+
+function easeInOutExpo(x: number): number {
+    return x === 0
+      ? 0
+      : x === 1
+      ? 1
+      : x < 0.5 ? pow(2, 20 * x - 10) / 2
+      : (2 - pow(2, -20 * x + 10)) / 2;
+}
+
+
+function easeInCirc(x: number): number {
+    return 1 - sqrt(1 - pow(x, 2));
+}
+
+function easeOutCirc(x: number): number {
+    return sqrt(1 - pow(x - 1, 2));
+}
+
+function easeInOutCirc(x: number): number {
+    return x < 0.5
+      ? (1 - sqrt(1 - pow(2 * x, 2))) / 2
+      : (sqrt(1 - pow(-2 * x + 2, 2)) + 1) / 2;
+}
+
+
+function easeInBack(x: number): number {
+    const c1 = 1.70158;
+    const c3 = c1 + 1;
+
+    return c3 * x * x * x - c1 * x * x;
+}
+
+function easeOutBack(x: number): number {
+    const c1 = 1.70158;
+    const c3 = c1 + 1;
+
+    return 1 + c3 * pow(x - 1, 3) + c1 * pow(x - 1, 2);
+}
+
+function easeInOutBack(x: number): number {
+    const c1 = 1.70158;
+    const c2 = c1 * 1.525;
+
+    return x < 0.5
+      ? (pow(2 * x, 2) * ((c2 + 1) * 2 * x - c2)) / 2
+      : (pow(2 * x - 2, 2) * ((c2 + 1) * (x * 2 - 2) + c2) + 2) / 2;
+}
+
+
+function easeInElastic(x: number): number {
+    const c4 = (2 * Math.PI) / 3;
+
+    return x === 0
+      ? 0
+      : x === 1
+      ? 1
+      : -pow(2, 10 * x - 10) * sin((x * 10 - 10.75) * c4);
+}
+
+function easeOutElastic(x: number): number {
+    const c4 = (2 * Math.PI) / 3;
+
+    return x === 0
+      ? 0
+      : x === 1
+      ? 1
+      : pow(2, -10 * x) * sin((x * 10 - 0.75) * c4) + 1;
+}
+
+function easeInOutElastic(x: number): number {
+    const c5 = (2 * Math.PI) / 4.5;
+
+    return x === 0
+      ? 0
+      : x === 1
+      ? 1
+      : x < 0.5
+      ? -(pow(2, 20 * x - 10) * sin((20 * x - 11.125) * c5)) / 2
+      : (pow(2, -20 * x + 10) * sin((20 * x - 11.125) * c5)) / 2 + 1;
+
+}
+
+
+function easeInBounce(x: number): number {
+    return 1 - easeOutBounce(1 - x);
+}
+
+function easeOutBounce(x: number): number {
+    const n1 = 7.5625;
+    const d1 = 2.75;
+
+    if (x < 1 / d1) {
+        return n1 * x * x;
+    } else if (x < 2 / d1) {
+        return n1 * (x -= 1.5 / d1) * x + 0.75;
+    } else if (x < 2.5 / d1) {
+        return n1 * (x -= 2.25 / d1) * x + 0.9375;
+    } else {
+        return n1 * (x -= 2.625 / d1) * x + 0.984375;
+    }
+}
+
+function easeInOutBounce(x: number): number {
+    return x < 0.5
+      ? (1 - easeOutBounce(1 - 2 * x)) / 2
+      : (1 + easeOutBounce(2 * x - 1)) / 2;
+}
+
+
+const funcs = [
+    easeInSine, easeOutSine, easeInOutSine, easeInQuad, easeOutQuad, easeInOutQuad,
+    easeInCubic, easeOutCubic, easeInOutCubic, easeInQuart, easeOutQuart, easeInOutQuart,
+    easeInQuint, easeOutQuint, easeInOutQuint, easeInExpo, easeOutExpo, easeInOutExpo,
+    easeInCirc, easeOutCirc, easeInOutCirc, easeInBack, easeOutBack, easeInOutBack,
+    easeInElastic, easeOutElastic, easeInOutElastic, easeInBounce, easeOutBounce, easeInOutBounce
+];
+
+const points = [
+    0.0,
+    0.05,
+    0.1,
+    0.15,
+    0.2,
+    0.25,
+    0.3,
+    0.35,
+    0.4,
+    0.45,
+    0.5,
+    0.55,
+    0.6,
+    0.65,
+    0.7,
+    0.75,
+    0.8,
+    0.85,
+    0.9,
+    0.95,
+    1.0
+];
+
+let PI = Math.PI;
+let cos = Math.cos;
+let sin = Math.sin;
+let pow = Math.pow;
+let sqrt = Math.sqrt;
+
+for (func of funcs) {
+    console.log(func.name);
+    let values = [];
+    for (point of points) {
+        values.push(func(point));
+    }
+    console.log(values);
+}