ions != null) {
  if (textureCoordinates != null &amp;&amp; textureCoordinates.length != positions.length)
    throw new ArgumentError(&#39;&quot;positions&quot; and &quot;textureCoordinates&quot; lengths must match.&#39;);
  if (colors != null &amp;&amp; colors.length != positions.length)
    throw new ArgumentError(&#39;&quot;positions&quot; and &quot;colors&quot; lengths must match.&#39;);
  if (indices != null &amp;&amp; indices.any((int i) =&gt; i &lt; 0 || i &gt;= positions.length))
    throw new Argu