isVerticalLine method
check if the drawn line on a vertical track
Implementation
bool isVerticalLine(List<LetterOffset> offsets) {
if (offsets.isEmpty) {
return false;
}
double firstX = offsets.first.getSmallerOffset.dx;
for (LetterOffset offset in offsets) {
if (offset.getSmallerOffset.dx != firstX) {
return false;
}
}
return true;
}