You can actually fire between the dots also.
If you want to fire when the line is , for an exampel, in the middle of of 2 and 3 dot you need to fire just when his line crosses yours at same point, Between his 2-3 dot also. The dots are there more just as an reference for you. But it would be easier if there was numbers on the line like a ruler.
But iam not sure if that is possible to mod cuz the line is not linier. Its dynamic. It change dependant what speed and direction you and the target have and also what speed you set your torps on.
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