It only checks a dot's x and y values. Instead, it should check the dot's flow position at the current beat.
To replicate, add a dot with a dot type with Eight to Five Static. The dot marches forward. Go forward a couple of beats. You will be unable to select the dot unless you click the position where the dot started at.
https://github.com/calband/calchart-redesign/blob/master/src/tools/BaseTool.ts#L61
It only checks a dot's x and y values. Instead, it should check the dot's flow position at the current beat.
To replicate, add a dot with a dot type with Eight to Five Static. The dot marches forward. Go forward a couple of beats. You will be unable to select the dot unless you click the position where the dot started at.