Lumberyard 1.22 game engine was just released by Amazon.
Highlights of this release from the release notes:
The primary change in this release is the new asset dependency system defined in depth in this blog post.
Enter asset dependency tracking. Lumberyard’s new Asset Dependency Graph provides the means to determine the set of assets a given asset depends on. By recursively walking the entire dependency graph, the engine can easily determine the exact set of assets your game needs to run. So when it comes time to release your game, packaging your assets becomes a simple set of steps as opposed to a several days-to-weeks development effort.
Now that the engine can determine which assets your game needs, our next task was to build a tool that packages a game’s assets into one or more asset bundles (single files that contain many assets packed together). Further, we added the ability to create new asset bundles that contain only those assets that have been added, changed, or deleted since the last asset deployment. This allows a game developer to do incremental content releases with only those assets that have actually changed since the last time they were shipped. Your players won’t have to waste time and bandwidth downloading new content or re-downloading old content.
Finally, because Lumberyard provides source code and encourages developers to modify Lumberyard to fit their needs, we added multiple validation systems that will alert the developer if they have done something that interferes with Lumberyard’s ability to generate a correct asset dependency graph.
Lumberyard is free for developers so long as they self host or use Amazon services for their networking. You can download Lumberyard here.