The problem is, you're not making any sense, because an angle doesn't face any particular direction. You can say anything you want about "real" angles, but a 30 degree angle isn't going to change if you turn it. I'm now beginning to wonder if you people ever even went to school, as you have no idea what I'm talking about even WITH the subject.
Dude, if you want people to help you out, this is the wrong way to go about it. And yes, I understand that a 30 degree angle is a 30 degree angle no matter which way it's facing. If I misunderstood your problem, it's only because you're withholding information that is relevant in helping you.
Which I now no longer care to do. Good luck.
Edit:
Hey, I think I'm perfectly justified in saying that.
No, you're just being a dick. Try explaining yourself instead of jumping to insults. I assumed you meant you wanted to calculate your sprite animation angle based on the three points, and that's the problem you were having. When I said "real angles" I assumed you understood that Construct's angles were fixed coordinates. What you want is to calculate the relative angle and translate that to Construct's fixed angle.
And again, good luck with that.