On 19.10.11 14:22, Arno Trautmann wrote: > Is there any technical documentation on how pdfTeX (or, if it differs > in that case, LuaTeX) breaks lines into paragraphs using font > expansion and character protrusion? Thanh's thesis would be your best bet, I guess: <http://www.tug.org/TUGboat/tb21-4/tb69thanh.pdf> Best, -- Robert