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    <h3>Steps</h3> <p>Here are a few steps in order to move your rectangle along a circle's rim <strong>when the user taps and holds</strong> to the side of the circle:<br> <strong>1.</strong> Obtain direction desired.<br> <strong>2.</strong> Obtain angle from current x and y coordinates.<br> <strong>3.</strong> Add direction (+1 if counterclockwise, -1 if clockwise) to angle.<br> <strong>4.</strong> Calculate new x and y coordinates.<br> <strong>5.</strong> Update/display rectangle. </p> <h3>Details</h3> <p><strong>1.</strong> In pseudocode, <code>direction = sign(Rectangle1.x - UsersFingerPosition.x)</code>. Here sign is a function returning -1 if the number was negative, 0 if it is 0, and 1 if it is positive. Note that <code>sign(0)</code> will only result when the user is on the exact x and y of your rectangle's location. In that case, the rectangle would not move (which should be good). In Java, the sign function is <code>Math.signum()</code>.</p> <p><strong>2.</strong> To obtain the current angle use the following java code:</p> <pre><code>double angle = Math.toDegrees(Math.atan2(Circle.y-Rectangle1.y, Rectangle1.x-Circle.x)); </code></pre> <p>Note the order of <code>Circle.y-Rectangle.y</code> and <code>Rectangle.x...Circle.x</code>. This is a result of the coordinate (0, 0) being in the top left corner instead of the center of the screen. </p> <p><strong>3.</strong> Simple enough, just add direction to angle. If desired, do something like</p> <pre><code>angle += direction*2; //So it will move more quickly </code></pre> <p><strong>4.</strong> To get the new x and y coordinates of your rectangle, use the trigonometric functions sine and cosine:</p> <pre><code>Rectangle1.x = Math.cos(Math.toRadians(angle))*Circle.radius + Circle.x - Rectangle1.width; Rectangle1.y = Math.sin(Math.toRadians(angle))*Circle.radius + Circle.y - Rectangle1.height; </code></pre> <p>(where Circle.x and Circle.y are the coordinates of the center of your circle and Circle.radius is naturally it's radius).</p> <p><strong>5.</strong> This one you'll have to take care of (or have already) :)!</p> <p>Hope this helps you!</p>
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    1. COthanks. in #2 should it not be (usersfingerposition.y, usersfingerposition.x), otherwise angle will always be the same?
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    2. COI'm sorry about #2, I messed it up! However, it should not be `users...` because `angle` is the angle from the center of the circle to the (x,y) coords of the rectangle. In that way you can 'rotate' the angle, which would move the rectangle around the circle. I'll edit #2 so that it is correct.
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    3. COIt's corrected!
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