多边形每边的中心

Question

嗨，我有一个带坐标的多边形

[
    [-73.9280684530257, 40.8099975343718],
    [-73.9282820374729, 40.8100875554645],
    [-73.9280124002104, 40.8103130893677],
    [-73.927875543761, 40.8102554080229],
    [-73.9280684530257, 40.8099975343718]
]

如何使用javascript查找此多边形每边的中心？

Answer 1

你可以通过取平均值来占据中心位置。

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var polygon = [[-73.9280684530257, 40.8099975343718], [-73.9282820374729, 40.8100875554645], [-73.9280124002104, 40.8103130893677], [-73.927875543761, 40.8102554080229], [-73.9280684530257, 40.8099975343718]],
    centers = polygon.map(function (point, i, points) {
        var neighbour = points[(i + 1) % points.length];
        return point.map(function (value, j) {
            return (value + neighbour[j]) / 2;
        });
    });

console.log(centers);

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.as-console-wrapper { max-height: 100% !important; top: 0; }

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Answer 2

另一种解决方案可以是这种形式

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var vertexArray = [[-73.9280684530257, 40.8099975343718], [-73.9282820374729, 40.8100875554645], [-73.9280124002104, 40.8103130893677], [-73.927875543761, 40.8102554080229], [-73.9280684530257, 40.8099975343718]];

var centerArray = [];
for(i=0;i<vertexArray .length;i++){
   nextIndex = (i+1)%vertexArray.length;
   centerArray[i] = [] ;
   centerArray[i][0] = (vertexArray [i][0] + vertexArray[nextIndex][0])/2;
    centerArray[i][1] = (vertexArray[i][1] + vertexArray[nextIndex][1])/2

}
console.log(centerArray);

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