Unreal Engine 4 (UE4) is a cross-platform, next-generation game engine created by Epic Games. Although the Engine itself proprietary, development is performed in an open fashion with full code sources hosted on GitHub.
Those interested in the source must register by creating a user account with Epic Games, link their GitHub accounts, and abide by all the rules outlined in the EULA. Redistribution is not permitted since each user must individually acknowledge and agree to the End User License Agreement (EULA).
Manually clone and build the sources
As mentioned in the summary, a few steps are necessary for each user to take in order to obtain the Unreal Engine sources:
The remainder of this article will presume the 4.9.2 sources will be used for the build process.
git clone -b 4.9.2 https://github.com/EpicGames/UnrealEngine.git
See official upstream documentation for the latest details of the build process.
In short, from the base of the sources directory, run:
./GenerateProjectFiles.sh # This is the equivalent of make configure
Finally, once all the binary assets have been acquired, run build the project:
From the base of the sources directory, start the engine via:
Clean and rebuild
As the upstream document says, if the project needs to be cleaned, run the following command:
Then rebuild the project with make.
Unreal Engine 4 build time
Build time for Engine on a i7-4790 CPU @ 3.60GHz, using all 8 cores:
Total build time: 3552.69 seconds real 70m31.064s user 320m39.870s sys 8m36.320s
Unreal Tournament 4 build time
Build time for Tournament on a i3770, using all 8 cores:
-------- End Detailed Actions Stats ----------------------------------------------------------- Total build time: 3643.06 seconds real 75m31.091s user 520m46.820s sys 9m3.400s