The PlayStation 4 release of Skullgirls Encore, Lab Zero Games' 2D fighting game, will let fighting game aficionados use their existing PlayStation 3 arcade sticks, thanks to a custom USB driver. And fans of other fighting games might benefit as well, as the developer says it will let others use its PS4 driver in their games, free of charge.

"Lab Zero feels very strongly about this: we think it's better for the consumer and the industry that you be able to spend your hard-earned money buying games instead of buying a new fight stick," Peter Bartholow, CEO of Lab Zero Games said in a statement.

Support for previous-generation arcade sticks and controllers on PS4 is not an official Sony feature, the Skullgirls developer says. Skullgirls Encore's support for PS3 sticks on PS4 will likely come with some limitations, too. But Lab Zero says it will be testing a variety of arcade sticks to ensure broader compatibility.

"Any stick that reads as a Generic USB GamePad or Joystick will work," Bartholow said in an email to Polygon. "This covers MadCatz TEs, which are the majority of what the fighting game community uses right now, as well as many other smaller brands and custom options such as the GodLike Controls' Cthulhu boards.

"With all the different custom sticks out there, we won't be able to test everything ourselves. So we'll be building out the compatibility list through public testing and listing it online, so people know what will work beforehand."

Bartholow says any device that identifies itself as a DualShock 3, instead of something more generic, won't work with its driver. The popular PS360+ board and Inpin PS2 to PS3 adapter will not work for this reason, Bartholow says. There's also no way to support PS4-specific features like the DualShock 4's Home and Share buttons, so players will need to rely on a standard controller for those functions. (That may actually be a benefit in tournament situations, where errant presses of the Home button might interrupt play.)

Otherwise, the driver is said to be basically plug and play, letting users swap controllers in and out.

Public testing for Lab Zero's USB driver kicks off this weekend and will continue at events like Sony's PlayStation Experience in Las Vegas this December. Lab Zero plans to have PS3 controller compatibility in place when Skullgirls Encore hits PS4 sometime next year. A compatibility list will be available online at a future date.

While the software that enables PS3 controller compatibility on PS4 isn't officially supported by Sony, it was developed by someone with intimate knowledge of PlayStation platforms. Naughty Dog programmer John "Cowboy" Bellomy wrote the new USB driver for Lab Zero in his free time, Lab Zero says, because it "sounded neat."

Once work on the PS3 to PS4 USB driver is complete, Lab Zero plans to let other developers use their code. There's no fee to do so, and other developers can build upon and adapt the driver. They just have to share their work with Lab Zero in return.

Here's a quick video of Skullgirls programmer Mike Zaimont showing off PS3 arcade stick compatibility on PS4.