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copied!<h2>A note on your actual question</h2> <p>Paths already do that. Lines, arcs, curves, etc. are all added from the current point. It looks like you are passing the current point for the x and y arguments in <code>CGPathAddArc(...)</code> but those arguments are used for the center of the arc, not the start.</p> <hr> <h1>A much better way of doing a donut chart.</h1> <p>That said, there is a much better way of doing donut charts. First you do the single arc in te center of the donut then you create a new path by stroking that arc. This allows you to customize the width of the donut very easily. I've described this and broken down the code in great detail in <a href="https://stackoverflow.com/a/15868472/608157">this answer</a> but here is a shorter version of the shape itself.</p> <h2>Code to do this</h2> <p>Create the arc in the center of the donut (orange line in the below image)</p> <p><img src="https://i.stack.imgur.com/3RRdU.png" alt="enter image description here"></p> <pre><code>CGMutablePathRef arc = CGPathCreateMutable(); CGPathMoveToPoint(arc, NULL, startPoint.x, startPoint.y); CGPathAddArc(arc, NULL, centerPoint.x, centerPoint.y, radius, startAngle, endAngle, YES); </code></pre> <p>Create a new path by stroking that path (dotted shape in the image above and filled shape in the image below):</p> <p><img src="https://i.stack.imgur.com/9IPag.png" alt="enter image description here"></p> <pre><code>CGFloat lineWidth = 10.0; CGPathRef strokedArc = CGPathCreateCopyByStrokingPath(arc, NULL, lineWidth, kCGLineCapButt, kCGLineJoinMiter, // the default 10); // 10 is default miter limit </code></pre>

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