Show HN: Tortuise – Gaussian splatting in your terminal, no GPU required

I had an itch on building something gaussian splats related. Especially after Apple dropped their image to splat open source model. Working with it on my headless Mac Mini realized that I want to see gaussian splats without leaving my terminal.

Built tortuise - it renders .ply and .splat scenes using CPU-only rasterization - halfblock characters, depth sorting, alpha compositing, all on the CPU - Rust + crossterm + rayon. Six render modes (halfblock, braille, ASCII, point cloud, matrix, block density), auto-detects truecolor vs 256-color terminals, modal Free/Orbit camera.

The interesting constraint: sorting 500K+ semi-transparent splats per frame with no GPU. Runs comfortably over SSH on a headless Mac Mini, even better locally - interactive framerates at reasonable terminal resolution on M2/M4. Tested down to a potato - Jetson Orin Nano (cpu). Recommend to use with Ghostty terminal or similar.

cargo install tortuise

Would love feedback on the rendering pipeline and any scenes you throw at it that break things.

Gone already?