 Various 3D frameworks have been built for Flash using Stage3D, such as Away3D 4, CopperCube, Flare3D and Starling.Professional game engines like Unreal Engine and Unity also export Flash versions which use Stage3D to render 3D graphics.Virtually all browser plugins for video are free of charge and cross-platform, including Adobe's offering of Flash Video, which was introduced with Flash version 6.