在基于focla点的坐标系上绘制一条椭圆线?

我正在尝试在Google地图上画一条虚线，所以我不能使用eshape.js.我需要创建一个在坐标系中近似椭圆的点数组.它只是用于显示，因此不必那么精确.

I'm trying to draw a dashed line on a google map, so I can't use eshape.js. I need to create an array of points that approximate an elipse in a coordinate system. It's just for display so it doesn't have to be that precise.

如果有人可以解释一下数学就很好了.如果您在javascript中应用它，会获得额外的信用；)

If someone can just explain the math that's fine. Extra credit if you apply it in javascript ;)