mirror of
https://kevinblog.sytes.net/Code/Jibo-Revival-Group/RoboCommander.git
synced 2026-06-15 19:16:01 +00:00
16 lines
243 B
JavaScript
16 lines
243 B
JavaScript
|
export default function(polygon) {
|
||
|
|
var i = -1,
|
||
|
|
n = polygon.length,
|
||
|
|
a,
|
||
|
|
b = polygon[n - 1],
|
||
|
|
area = 0;
|
||
|
|
|
||
|
|
while (++i < n) {
|
||
|
|
a = b;
|
||
|
|
b = polygon[i];
|
||
|
|
area += a[1] * b[0] - a[0] * b[1];
|
||
|
|
}
|
||
|
|
|
||
|
|
return area / 2;
|
||
|
|
}
|