cocoscreater 旋转角度计算

getVectorRadians( x1, y1, x2, y2)

{

let len_y = y2 - y1;

let len_x = x2 - x1;

let tan_yx = tan_yx = Math. abs( len_y)/ Math. abs( len_x);

let angle = 0;

if( len_y > 0 && len_x < 0) {

angle = Math. atan( tan_yx)* 180/ Math.PI - 90;

} else if ( len_y > 0 && len_x > 0) {

angle = 90 - Math. atan( tan_yx)* 180/ Math.PI;

} else if( len_y < 0 && len_x < 0) {

angle = - Math. atan( tan_yx)* 180/ Math.PI - 90;

} else if( len_y < 0 && len_x > 0) {

angle = Math. atan( tan_yx)* 180/ Math.PI + 90;

}

return angle;

},

需要拿走