Unity Game Optimization - Third Edition

Making use of Occlusion Culling

One of the best ways to reduce both Fill Rate consumption and Overdraw is to make use of Unity's Occlusion Culling system. The system works by partitioning the world into a series of small cells and flying a virtual camera through the scene, making a note of which cells are invisible from other cells (are occluded) based on the size and position of the objects present.

Note that this is different from the technique of Frustum Culling, which culls objects outside the current camera view. Frustum Culling is always active and automatic. Objects culled by this process are, therefore, automatically ignored by the Occlusion Culling system.

Occlusion Culling data can only be generated for objects properly labeled ...