Equation For Specific Line Length Needed

[bplus]

Ah yes, when my = heroY then the difference is 0 and will get division by 0 error, unless _ATAN2() can "tolerate" that condition which is possible if _ATAN2() were good because that is likely problem. So test my code and see if throws error when mouse is level with HeroY.

Update: Yeah, seems OK when my = HeroY so _ATAN2() can handle 0 in the 2nd argument. It has no problem drawing horizontal swords.