Of all those at the high table, only Sansa Stark was not smiling. He could have loved her for that, but if truth be told the Stark girl’s eyes were far away, as if she had not even seen the ludicrous riders loping toward her.
Ok, this is where I get to “the show is more explicit but the books are crueler.” The riders were more obscene in the show; they mocked more characters and more deaths more horribly. The Red Wedding and Renly/Loras are the other two subjects most clearly mocked in the show’s version of Joffery’s joust. In the show, no one is smiling but Joffery, Cersei, and a few extras.
In the books, Tyrion is all alone. He’s being mocked by everyone, and there’s no one else subjected to it. So however much more initially shocking the show’s scene is, the scene in the book is so much more painful to read.