Hi, according to the LuaTeX manual for node.setglue:

When you pass values, only arguments that are numbers are assigned so node.setglue(n,655360,false,65536) will only adapt the width and shrink.

This does not correspond to the actual behaviour. In practise, arguments which are not numbers are treated as zero: \directlua{ local n = node.new'glue' node.setglue(n, 100000, 100000, 100000, 2, 2) print('BEFORE', node.getglue(n)) node.setglue(n, 655360, false, 655360) print('AFTER', node.getglue(n)) node.free(n) } \bye prints BEFORE 100000 100000 100000 2 2 AFTER 655360 0 655360 0 0 The documentation should probably be adjusted to reflect the actual behaviour. - Marcel