Z-buffering

A z-buffer, also known as a depth buffer, is a type of data buffer used in computer graphics to store the depth information of fragments. The values stored represent the distance to the camera, with 0 being the closest. The encoding scheme may be flipped with the highest number being the value closest to camera. In a 3D-rendering pipeline, when an object is projected on the screen, the depth (z-value) of a generated fragment in the projected screen image is compared to the value already stored in the buffer (depth test), and replaces it if the new value is closer. It works in tandem with the rasterizer, which computes the colored values. The fragment output by the rasterizer is saved if it is not overlapped by another fragment. Z-buffering is a technique used in almost all contemporary computers, laptops, and mobile phones for generating 3D computer graphics. The primary use now is for video games, which require fast and accurate processing of 3D scenes.