operator * method
定位参数有值的倍数相乘
Implementation
operator *(double scale) {
double? start;
double? end;
double? center;
if (this.start != null) {
start = this.start! * scale;
}
if (this.end != null) {
end = this.end! * scale;
}
if (this.center != null) {
center = this.center! * scale;
}
return BubblePosition._(start, end, center);
}