The Z-buffer, or depth buffer, is a critical component in 3D graphics rendering. It stores depth information for each pixel in a 3D scene, indicating the distance from the viewer’s perspective. This depth information is essential for rendering objects in the correct order, ensuring that closer objects obscure those farther away and contributing to the illusion of a three-dimensional space.

Consider a scene with overlapping objects – the Z-buffer helps determine which object should be visible at any given pixel on the screen. The depth values stored in the Z-buffer enable the rendering engine to prioritize the correct order of objects, preventing visual anomalies like “z-fighting,” where surfaces flicker or appear distorted due to conflicting depth information.