Firstly we had to reduce the memory used by the assets in the game. We used smart algorithms to compress the used meshes for our geometry, the terrain height maps and terrain textures, the sprites that are used to display our vegetation in the distance and the animations used for our characters.
We also optimized how the memory was used and organized in our engine, which allowed us to increase the Streaming Buffer, which was very essential for making our large levels work.
Many of the effects now showcased in games are done via fullscreen shader passes. For example to convey motion blur, the render information of the whole screen is being processed with algorithms creating the desired effect. We already improved those algorithms in Crysis 2, but further optimized this for the Crysis 1 console version in order to save performance and processing time.
We refined the Occlusion Buffer we use to detect which objects we do not need to render since they would be occluded from other objects that are in front of them and used Reprojection methods to predict where the player might look next in order to avoid objects popping suddenly into place.
