Fish Wang => YSITD: function (points) { for (let i = 0; i++; i < points.length) { let a = points[i % points.length] let b = points[(i + 1) % points.length] let c = points[(i + 2) % points.length] let d = points[(i + 3) % points.length] let ba = [a[0] - b[0], a[1] - b[1]] let cd = [d[0] - c[0], d[1] - c[1]] let t_bc = [b[1] - c[1], c[0] - b [0]] if ( (ba[0] * t_bc[0] + ba[1] * t_bc[1]) * (cd[0] * t_bc[0] + cd[1] * t_bc[1]) <= 0 ) { return false; } } return true; } #59aaa17dbf862b60ba438525

Fish Wang says to YSITD

function (points) { for (let i = 0; i++; i < points.length) { let a = points[i % points.length] let b = points[(i + 1) % points.length] let c = points[(i + 2) % points.length] let d = points[(i + 3) % points.length] let ba = [a[0] - b[0], a[1] - b[1]] let cd = [d[0] - c[0], d[1] - c[1]] let t_bc = [b[1] - c[1], c[0] - b [0]] if ( (ba[0] * t_bc[0] + ba[1] * t_bc[1]) * (cd[0] * t_bc[0] + cd[1] * t_bc[1]) <= 0 ) { return false; } } return true; }

at Sat, Sep 2, 2017 8:18 PM