He was the most likable of the young things in the “Taming of the Shrew”-derived teenage comedy “10 Things I Hate About You,” with his curly hair, high forehead and the permanent intimation of a smirk on his thin-lipped, angled mouth. And as often happens with young actors in Hollywood, his good looks and easy charm looked like a ticket to the commercial big time. Dutifully, but also with sparks of playful, eager energy, he played period golden boys in “The Patriot” and “A Knight’s Tale,” a misbegotten (but not entirely unenjoyable) entry in the ever-silly costume-action genre.