我有这样的代码:
<defs>
<g id="g0">
<circle cx="0" cy="1" r="16" fill="blue" id="pr0" stroke-width="0" stroke="#2986dc"/>
<circle cx="0" cy="0" r="14" fill="red" id="pp0" />
</g>
</defs>
<use x="603" y="484" id="u0" href="#g0">
<animateTransform attributeName="transform" attributeType="XML" type="rotate" id="t0" dur="30s" repeatCount="indefinite" from="0 494 494" to="360 494 494"/>
</use>
如何使用 JavaScript 在动画期间获取组的坐标?