In a cruel bit of irony for Carmelo Anthony, the Rockets are making an appearance on the Knicks’ preseason schedule, visiting the Garden on Oct. 9. According to widespread reports, Anthony has told the Knicks he is willing to waive his no-trade clause only for the Rockets, who feature his two buddies, Chris Paul and James Harden. Teams such as the Cavaliers, Pelicans and Thunder have expressed interest, and The Post has reported the Knicks have talked to Anthony about expanding his wish list, to no avail. The only deal that makes sense under the salary cap includes Rockets power forward Ryan Anderson as the centerpiece of a trade, with three years and $60 million left on his contract, but he is overpriced and plays the same position as Kristaps Porzingis. Hence, the Rockets and Knicks never got close to a deal and have failed to find another team to join in on a three-team package. The Knicks could be better served waiting until the next important trade marker – Dec. 15 – when all the free agents who signed this summer are eligible to be moved. There’s a chance Anthony will be forced to attend training camp, which starts Sept. 24 in Tarrytown. The Knicks have the leverage now, as their chief objective is developing their young players this season and making the playoffs is not the No. 1 priority. The Knicks have all their first-round draft picks going forward.