public static string ToDebugString(this S2LaxPolygonShape polygon, string loop_separator = ";\n")
{
var sb = new List <String>();
for (var i = 0; i < polygon.NumLoops; ++i)
{
var n = polygon.NumLoopVertices(i);
if (n == 0)
{
sb.Add("full");
}
else
{
sb.Add(AppendVertices(polygon.LoopVertices(i, 0, n), n));
}
}
return(String.Join(loop_separator, sb));
}