class="keyword">function</span> removeClickFromStack(obj, x, y)
            position = obj.indexOf(x, y);

            <span class="keyword">if</span> position == -1
                <span class="comment">% The point doesn't exist, so can't remove it</span>
                <span class="keyword">return</span>
            <span class="keyword">end</span>

            obj.stack(position, :) = [];
        <span class="keyword">end</span>
</pre><h2>paint<a name="13"></a></h2><p>Add a point to the CData and update