A specific spot with unspecific coordinates

[font=Arial]I modified the falling snow to move upwards to make bubbles, but now I want them to come from a specific spot from movie clip which is moving constantly and roating. They also have to stay within the bounds of the water.
I tried placing it on the spot I want on the movie clip, and alter the code like so:


 onClipEvent (load) {
 	//variables that will modify the rising bubbles
 	i = 1+Math.random()*2;
 	k = -Math.PI+Math.random()*Math.PI;
 	
 	//giving each bubble unique characteristics
 	this._xscale = this._yscale=50+Math.random()*100;
 	this._alpha = 75+Math.random()*100;
 }
 onClipEvent (enterFrame) {
 	//putting it all together
 	rad += (k/180)*Math.PI;
 	this._x -= Math.cos(rad);
 	this._y -= i;
 	if (this._y<=_root.waterLevel) {
 	//go to the clip which duplicates the bubbles
 		this._y = _parent._y;
 		this._x = _parent._x;
 	}
 	if ((this._x>=555) || (this._x<=45)) {
 		this._y = _parent._y;
 		this._x = _parent._x;
 	}
 }
 

But with that, the bubble clip ends up 100 pixels behind where i placed it, and theres no movement or duplication. :h:
[/font]

I hate when I make a forum post and figure part of it out on my own…

I broke the first rule: the movie clip has to be at 0,0 for it work properly

To properly place the bubbles however, I first find the difference in coordinates between the target and what im placing, then instead of

 this._y = _parent._y; 

I change them to

 this._y = _root.target._y + dy 

where dy is target._y - location._y;

But that’s the easy part. Here is the tricky part:
That doesn’t factor in the rotation! (dun dun dun)

The target is rotating at:

Math.sin(timenow+.9)*2;

where timenow is the milliseconds converted into seconds.
So, how does the rotation effect dx and dy? (My trig is rusty :blush: )
----EDIT-----
Ok! I’ll answer my own question again before somsone can point me to this tuitorial

Using my dx and dy, I need to find the hypotenuse of an imaginary right triangle, the hypotenuse is the line beginning from the target._x and _y and stretching to my location._x and _y. Then… I rotate it by the same rotation and convert back to dx and dy, and I do all of this using mathmatics. None of which I can do. I’ll go study now.