Epic has announced that it's significantly raised the revenue ceiling for its Unreal Development Kit, the free version of its popular Unreal Engine 3.Since 2009, the company's been making UE3 available to anyone with interest in exploring game development, from students and hobbyists to independents, for free via the UDK program -- and did not collect royalties on revenues from products made with UDK until that revenue exceeded $5,000.Now, however, that threshold is set at $50,000, the company revealed on its developer forums "We're really excited about folks making some amazing things with UDK and we realize that a lot of you are just started in the business, so not having to pay royalties on your first $50,000 should help you get a financial footing toward building a quality game development business," said Epic VP Mark Rein.Rein also clarified that the royalties Epic collects come from the wholesale revenues -- the amount developers receive after the (typically 30 percent) retailer cut.Creators using UDK still need to sign an official licensing agreement, under which Epic receives 25 percent of revenue after the first $50,000 is made.