line"><a id="l00141" name="l00141"></a><span class="lineno">  141</span>    c.z = (box.upper.z + box.lower.z) * 0.5;</div>
<div class="line"><a id="l00142" name="l00142"></a><span class="lineno">  142</span>    <span class="keywordflow">return</span> c;</div>
<div class="line"><a id="l00143" name="l00143"></a><span class="lineno">  143</span>}</div>
<div class="line"><a id="l00144" name="l00144"></a><span class="lineno">  144</span> </div>
<div class="line"><a id="l00145" name="l00145"></a><span class="line