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README.md

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+Harmonica
+=========
+
+<p>
+    <a href="https://github.com/charmbracelet/harmonica/releases"><img src="https://img.shields.io/github/release/charmbracelet/harmonica.svg" alt="Latest Release"></a>
+    <a href="https://pkg.go.dev/github.com/charmbracelet/harmonica?tab=doc"><img src="https://godoc.org/github.com/golang/gddo?status.svg" alt="GoDoc"></a>
+    <a href="https://github.com/charmbracelet/harmonica/actions"><img src="https://github.com/charmbracelet/harmonica/workflows/build/badge.svg" alt="Build Status"></a>
+</p>
+
+A simple, efficient spring animation library for smooth, natural motion.
+
+```go
+import "github.com/charmbracelet/harmonica"
+
+// A thing we want to animate.
+sprite := struct{
+    x, xVelocity float64
+    y, yVelocity float64
+}{}
+
+// Where we want to animate it.
+const targetX = 50.0
+const targetY = 100.0
+
+// Initialize a spring with framerate, angular frequency, and damping values.
+spring := harmonica.NewSpring(harmonica.FPS60, 0.8, 0.98)
+
+// Animate!
+for {
+    spring.Update(&sprite.x, &sprite.xVelocity, targetX)
+    spring.Update(&sprite.y, &sprite.yVelocity, targetY)
+    time.Sleep(time.Second/60)
+}
+```
+
+For details, see the [examples][examples] and the [docs][docs].
+
+[examples]: https://github.com/charmbracelet/harmonica/tree/master/examples
+[docs]: https://pkg.go.dev/github.com/charmbracelet/harmonica?tab=doc
+
+## Acknowledgements
+
+This library is a fairly straightforward port of [Ryan Juckett][juckett]’s
+excellent damped simple harmonic oscillator originally writen in C++ in 2008
+and published in 2012. [Ryan’s writeup][writeup] on the subject is fantastic.
+
+[juckett]: https://www.ryanjuckett.com/
+[writeup]: https://www.ryanjuckett.com/damped-springs/
+
+## License
+
+[MIT](https://github.com/charmbracelet/harmonica/raw/master/LICENSE)
+
+***
+
+Part of [Charm](https://charm.sh).
+
+<a href="https://charm.sh/"><img alt="The Charm logo" src="https://stuff.charm.sh/charm-badge-unrounded.jpg" width="400"></a>
+
+Charm热爱开源 • Charm loves open source