Fei-Fei Li's World Labs open-sources Spark 2.0, streaming rendering of over 100 million 3D Gaussian points within the browser

ME News Report, April 15 (UTC+8), according to 1M AI News monitoring, spatial intelligence company World Labs released the open-source 3D Gaussian Splatting (3DGS) rendering engine Spark 2.0. Its core capability is streaming and rendering over 100 million Gaussian points (splats) to form large-scale 3D scenes in browsers on any device, covering desktop, iOS, Android, and VR headsets. Spark is built on THREE.js and WebGL2, the latter being the 3D graphics interface supported by almost all devices today. Most consumer-grade devices can only render 1 to 5 million Gaussian points at interactive frame rates, while large 3D scans often contain tens of millions or even hundreds of millions of points, with raw data sizes exceeding 1GB. Version 2.0 addresses this bottleneck with three new technologies: 1. Level of Detail (LoD) system: organizes all Gaussian points into a hierarchical tree, where each parent node is a low-resolution approximation of its children. During rendering, it automatically traverses from coarse to fine based on the viewing angle, selecting the optimal subset, and ensuring stable frame rates by setting a rendering budget (500k to 2.5 million points), independent of the total scene point count. 2. Progressive streaming: the newly designed .RAD file format supports random access and progressive transmission. When opening a scene, a rough outline composed of 64k points is displayed immediately, followed by gradual loading of details prioritized by viewing angle, with automatic re-prioritization as the user moves. 3. Virtual VRAM management: allocates a fixed 16 million point memory pool on the GPU, with pages of 64k points that are automatically swapped in and out, similar to an operating system’s virtual memory mechanism, allowing limited VRAM to access nearly unlimited scene data. The core algorithm is written in Rust and compiled to WebAssembly, running in a background Web Worker thread to avoid blocking the main rendering loop. Spark was originally an internal renderer developed by World Labs for its 3D world generation product Marble, later open-sourced as a general tool. The release also showcased multiple community projects, including a multiplayer space shooter game Starspeed built with Marble and Spark, featuring a scene with over 100 million Gaussian points, running directly in the browser. (Source: BlockBeats)