#!/usr/local/bin/perl -n

@x = ( { Begin => "{", End => "}" }, "(?:Attribute|Motion|Transform|World|Frame)" );

$i-- if(/^\s*$x[1]End/ && $i);

/^\s*\#/?s/^\s*//:s/^\s*/" "x(4*$i)/e;
s/^(\s*$x[1](Begin|End).*)$/$1.(m|\#[\{\}]$|?"":" #$x[0]{$2}")/e;

print;

$i++ if(/^\s*$x[1]Begin/);