I require a custom game engine, capable of rendering a sandbox game consisting of editable cubes. This would be similar to the game "Minecraft", although each cube should scale to around 32mm instead of 1M. The engine needs to be able to render at least 1KM of terrain laterally, and at least 1KM of terrain vertically. The engine will also need to adjust the detail level of the render based on distance, EG the farther away an object is, the less detail it is drawn with in order to increase video performance. The engine should support worlds at least as large as north america. Also, it must include options to change render distance and detail as well as shaders in order to allow lower end computers to run it. The project must run on all recent versions of Windows, Mac, and Linux, preferably using Java however this is negotiable. You will NOT be needed to program any game content, networking code, etc. only the rendering engine itself. I have attached a picture of a similar game. (Minecraft) It will need to render environments such as this, except with much smaller editable cubes and be able to render a larger area.