texture-compression-astc-sliced-3d
Specification: WebGPU § texture-compression-astc-sliced-3d
This extends ASTC texture compression to textures created with dimension: "3d". Each depth slice uses the existing two-dimensional ASTC block formats, so an application can sample a compressed volume directly through a 3D texture view.
It is useful for volumetric effects, baked lighting, and other volume assets where uncompressed storage is expensive. The block-size tradeoff applies within each slice: larger ASTC blocks reduce storage but lose detail. This feature does not expose ASTC’s separate volumetric block encodings or add HDR texture formats.
Request the sliced-3D feature only when the adapter exposes it. Its dependency is texture-compression-astc, which current WebGPU enables implicitly; explicitly requesting both supported tokens is also valid. Base ASTC support alone is insufficient for a 3D texture. Keep an uncompressed volume fallback, or use a 2D array and implement interpolation between slices in the shader.
Availability by month
| Month | With feature | Eligible reports | Availability |
|---|---|---|---|
| 2026-08 | 31 | 106 | 29.2% |
| 2026-09 | 6 | 36 | 16.7% |
By browser (last 30 days)
| Browser | Availability | n |
|---|---|---|
| chrome | 34.4% | 90 |
| edge | 12.5% | 8 |
| firefox | 11.4% | 44 |
Availability = share of first-party, non-quarantined reports with WebGPU on a hardware (non-fallback) adapter that expose this feature. Developer-leaning sample. Full methodology.