### Targeting point

I have to do some calculations.

In short, the math exercise is :
 Double xCurrentPt, yCurrentPt; Double xTargetPt, yTargetPt; Double angle;

Suppose a man is standing at position xCurrentPt, yCurrentPt and with angle "Angle". Now he want to move to position xTargetPt, yTargetPt. Before walking he must rotate himself to a proper angle value. He'll continue to walk with his speed 'fSpeed' until he's reached the Target position (xTargetPt, yTargetPt)

The problem is I can't get the new right angle when the target has been changed.
Eg :
 xCurrentPt = 200; yCurrentPt = 250; Angle = 72ยบ Target : xTargetPt : 125; yTargetPt : 865; Angle : ???????????

How to get the angle (or radian) between the current point and the target point? What the function is used to do this? Help please...
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This might help you: http://en.wikipedia.org/wiki/Triangle#Computing_the_sides_and_angles

As the length of the triangle sides you should use the x and y distance of the man to the target. For example:

 ``12`` ``````double horizontalLine = xTargetPt - xCurrentPt; double verticalLine = yTargetPt - yCurrentPt;``````

Now all you need to do is to calculate the angle between those two lines (think of it as a triangle, which means, connect the end of the horizontalLine with the end of the verticalLine). It probably helps to make a sketch.

By the way: You get all the trigonometric functions you need through the cmath ( http://www.cplusplus.com/reference/clibrary/cmath/ ) library.
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