Show HN: DirectXSplat – D3D12 Gaussian splat renderer, up to 2.4× gsplat FPS

Hi all,

Over the past few months, I've been working on and off on DirectXSplat, a C++/Direct3D 12 library for rendering 3D Gaussian Splats. It can load PLY, SPZ, .splat, SOG, and lod-meta.json scenes and render them from a host D3D12 application.

Features:

- GPU-accelerated D3D12 rasterization

- Up to 2.4x the FPS of gsplat in matched-quality, resident-scene benchmarks on an NVIDIA GeForce RTX 4070 SUPER

- Native embeddable D3D12 renderer with a host-owned device, queue, command list, fences, and render targets

- Compact packed GPU scene buffers, persistent uploaded scenes, and reusable renderer resources

- No CUDA dependency for DirectXSplat rendering

- Support for trained 3DGS scenes in PLY, SPZ, .splat, and SOG formats, plus lod-meta.json scene manifests

- Whole-scene updates and uploaded scene/chunk mutation

- GPU resource interop for external work that references renderer-owned resources

- Optional approximate splat-depth output

- Convenience APIs including an interactive viewer through Show(...) and offscreen image capture through Draw(...)

Some of the performance work includes an adapted GPU OneSweep radix sort, GPU-side culling and compaction, and indirect dispatch and draw arguments based on the surviving splats. Scene data is stored in compact packed GPU buffers. Uploaded scenes and renderer-owned resources persist and are reused between frames. Large scenes are internally partitioned into chunks and support hierarchy-based visibility, screen-space LOD selection, configurable splat and residency budgets, and residency caching.

The project is MIT licensed and completely open source.