Epic has made Unreal Engine 4 available for free to anyone who wants to use it.

The engine can be used for any purpose any user sees fit, whether it be game development, education, architecture, and visualisation to VR, film and animation, said Epic. The only stipulation on the engine's use is a 5 percent royalty on gross revenue after the first US$3,000 per product, per quarter.

"It’s a simple arrangement in which we succeed only when you succeed," said Epic in a blog post.

The download features the full toolset and includes 100 percent of the C++ source code. Epic will release all future updates to the engine at no additional cost.

In addition, the download provides access to a wiki, development forums and a marketplace where users can sell their work and buy the work of others. There are also video tutorials, documentation and some basic game templates included.

“The past year has been a whirlwind for everyone at Epic Games. Our community has grown tremendously. The quality and variety of creative work being done has been breathtaking. When we asked people to submit their projects to be shown this year at GDC, we had the challenge of picking just 8 from over 100 finalists that were all good enough to show,” said Epic Games boss Tim Sweeney.

“The state of Unreal is strong, and we’ve realized that as we take away barriers, more people are able to fulfil their creative visions and shape the future of the medium we love. That’s why we’re taking away the last barrier to entry, and going free.”