Decide if touch position is left, top, right or down from specific point

Question

How do I decide if touch position of user input is (more likely) left, top, right or bottom from specific point? I know how to get position of touch, but don't know how to decide which "way" it is.

@Override
public boolean onTouch(View v, MotionEvent event) {
    if(event.getAction() == MotionEvent.ACTION_DOWN){
        //...
    }
    return false;
}

Demonstration image:

Answer 1

Assuming those are 45 degree angles, then

dy = pointY- currentY
dx = pointX- currentX
if(abs(dy) > abs (dx) && dy <0 ) return bottom
else if(abs(dy) - abs (dx)) return top
else if(dx < 0) return right
else if (dx > 0) return left
else return same point

If those aren't 45 degree angles, you're going to have to use trig to figure out where the boundaries are.