在边上创建一个运动的箭头元素时，如何使箭头始终指向当前边的切线方向？ #3151

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What problem does this feature solve?

如案例：https://g6.antv.vision/zh/examples/scatter/edge/ 中所示，我将案例中的原点替换成了一个箭头，但这个箭头始终都是朝左的。如何能够使该箭头始终指向当前边的切线方向？ codesandbox: https://codesandbox.io/s/boring-surf-emgbk?file=/index.js

What does the proposed API look like?

技术咨询。

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