We describe a new method of game streaming designed to address the limitations of video-based cloud gaming and graphics API command streaming approaches. The method is implemented as a game-engine protocol and plug-in called GPEG (Geometry Pump Engine Group). GPEG streams the game engine content as sub-assets, not video of gameplay or graphics API commands. GPEG encoding uses unique pre-processing algorithms which intelligently subdivide textured mesh assets into much smaller sub-assets based on their potential geometric and perceptual visibility. A thin, CPU-only, server software process interactively streams the pre-encoded sub-asset packets to the client-side game engine using navigation-driven, visibility-based prefetch. Like command streaming, the method does not require a GPU on the server. By using predictive prefetch, the method overcomes network latency. In contrast to progressive download, the method is a true content stream, with adaptive scalability and intelligent caching that together enable interactive game engine content streaming over broadband.