public override int Compare(VertexKey a, VertexKey b)
{
return(Comparer.CombinedCompare(
floatComparer,
a.normal.x, a.normal.y, a.normal.z, a.uv.x, a.uv.y,
b.normal.x, b.normal.y, b.normal.z, b.uv.x, b.uv.y));
}