3D Gaussian Splatting (3DGS) has emerged as a powerful alternative to NeRF for novel view synthesis, offering real-time rendering without sacrificing quality. This article breaks down the core rendering pipeline: starting from the mathematical definition of 3D Gaussian ellipsoids, it explains how covariance projection maps these ellipsoids to 2D screen space. Spherical harmonics are used to encode view-dependent color, enabling realistic appearance from any angle. A tile-based depth sorting algorithm then orders the splats, followed by alpha blending to produce the final image. The combination of these techniques allows 3DGS to render high-quality scenes at interactive frame rates, making it ideal for applications in virtual reality, digital twins, and 3D reconstruction. For graphics engineers and researchers, understanding this pipeline is crucial for optimizing and extending 3DGS in production systems.
A deep dive into the 3DGS rendering pipeline, covering Gaussian ellipsoid math, covariance projection, spherical harmonics, and tile-based sorting for real-time novel view synthesis.