">77</a></span><span class="t">        <span class="com"># Move to top-left corner, possibly offset if c0 is exposed</span>&nbsp;</span><span class="r"></span></p>
    <p class="pln"><span class="n"><a id="t78" href="#t78">78</a></span><span class="t">        <span class="com"># (meaning both top and left edges are external).</span>&nbsp;</span><span class="r"></span></p>
    <p class="mis show_mis"><span class="n"><a id="t79" href="#t79">79</a></span><span class="t">        <span class="nam">start_x</span>