flow like the river

BACK_BACK/node_modules/d3-ease/src/cubic.js

@@ -0,0 +1,11 @@
+export function cubicIn(t) {
+  return t * t * t;
+}
+
+export function cubicOut(t) {
+  return --t * t * t + 1;
+}
+
+export function cubicInOut(t) {
+  return ((t *= 2) <= 1 ? t * t * t : (t -= 2) * t * t + 2) / 2;
+}