World Labs’ Spark library, the Gaussian Splatting renderer for Three.js, continues to mature quickly. Version 0.1.9 introduces new creative effects, interactive workflows, and a round of under the hood optimizations that make gaussian splats feel more alive in the browser.

The most eye catching addition in Spark 0.1.9 is a suite of new transition and reveal effects that bring a surprising sense of motion and drama to splat based scenes. Instead of simply appearing on screen, splats can now emerge in far more expressive ways. A “Magic” effect radiates outward with distortion and noise, compressing at the edges while scales pulse dynamically. “Spread” creates a softer emergence, with splats blooming from the center and gradually fading as they expand. “Unroll” twists splats into view like a helical scroll, revealing them vertically as if the scene is being unfurled in space. Then there’s “Twister,” a tornado like vortex that swirls with height dependent motion. Finally, “Rain” drops splats through the scene in falling streaks, with drag, compression, and depth based fading evoking the look of weather in motion.

These effects are showcased in an interactive weather demo that lets users switch between tornadoes and rainstorms through a simple dropdown, with parameters adjustable in real time. Under the hood, they’re powered by Spark’s Dyno shader system.

Alongside reveals, Spark now supports two dedicated transition effects designed to make scene changes more cinematic. “Explosion” sends splats flying in bursts that obey gravity and bounce back into place, while “Flow” distorts them into wave-like currents that ripple across the model. Paired with real time camera controls and automatic cycling between models, these transitions point to Spark’s potential as a lightweight platform for interactive storytelling in the browser.

Finally, Spark introduces an example for brush based splat painting and erasing. While experimental, it represents a first step toward interactive editing. It is a bit reminiscent of NVIDIA's Painting with Gaussian Splatting Brushes, which is greatly exciting to see.

Spark 0.1.9 also brings important format and projection upgrades. The renderer now supports SPZ v3, ensuring compatibility with the latest compressed splat pipelines and improving the accuracy of Gaussian rotation quantization for sharper reconstructions. At the same time, orthographic rendering has been introduced, taking advantage of Three.js’ isOrthographic uniform. This allows developers to step beyond perspective-only views, making Spark more flexible for different visualization needs.

Underneath the new visuals, the team has continued to fine-tune Spark’s performance. Memory allocations during PLY loading have been trimmed down, while a compiled parser function speeds up .ply file imports. SOGs files now benefit from precomputed lookup tables, reducing overhead during playback. Even small details, such as avoiding unnecessary Quaternion allocations or using native Float16Array support when available, add up to smoother performance across large datasets. Other improvements include a call to gl.flush() to encourage eager GPU execution and consistent resizing behavior across all examples.

Spark continues to be free to use and MIT Licensed. It is exciting to see more editing capabilities emerge from the company, especially as they have begun unveiling their newest generative model, Marble.