Online Games Framework For Immersive Display

With the rapid development of network technology and application, Internet has become essential to people's daily life and work. Online entertainment, information query and instant messaging have become three most important applications of Internet. As an important part of the entertainment industry, online games reserve large market share, and have turned into a major profit growth point. The traditional online game architecture is composed of game server and game client. The client is run on PC, with LCD monitors of small screens and narrow field of view. The players do not have strong immersive experience in the course of gaming.This thesis presents an immersive display framework tailored for online game. The framework runs game clients on a cluster for generating images of high resolution and wide field of view. It displays images using multi-channel projectors to cast them on large scale cylinder screen, which offers strong immersive experience. Based on this framework, the architecture of immersive online game is factored into game server, master node and slave nodes. The master and slave nodes are implemented by modifying source code of the game client, and these nodes are organized in one PC cluster. In this framework, the master node receives input events from player, communicates with the server, receives the status of game objects updated the game server. Then, it sends the status data to each slave node before each frame is rendered by the modified game client. Finally, it sends the frame synchronization signal to slave nodes for swapping frame buffers. The slave nodes are responsible for rendering the game world. Setting parameters of virtual cameras of slave nodes, the contents of frame buffers can have overlap regions. For displaying the contents seamlessly on cylinder screen, they are first deformed followed by geometry and color calibrations carried out on slave nodes. Through the optical systems of projectors, one high-resolution, large scale image is displayed seamlessly on the cylinder screen, which provides the immersive experience to the player.Experimental results show that the framework running on PC cluster provides the immersive experience, and runs smoothly with little overhead in terms of FPS. The network bandwidth for exchanging data and frame synchronization among nodes dependents on result of multiplying the number of moving game objects with bits number of updating the status of one game object. The evaluation with different numbers of slave nodes shows our framework is scalable.