step method
返回其 step图形样式坐标点
Implementation
List<Offset> step([double ratio = 0.5]) {
if (_pointList.length <= 1) {
return [..._pointList];
}
List<Offset> list = [];
for (int i = 0; i < _pointList.length - 1; i++) {
Offset cur = _pointList[i];
Offset next = _pointList[i + 1];
list.add(cur);
double x = (cur.dx + next.dx) * ratio;
list.add(Offset(x, cur.dy));
list.add(Offset(x, next.dy));
}
list.add(_pointList[_pointList.length - 1]);
return list;
}