SimVX Textures Basis

SimVX's native texture transcoder: basis_universal turns UASTC .ktx2 textures into the block format the GPU samples (BC7, ASTC 4x4 or ETC2). Most users want simvx, which includes it where a wheel exists.

Pre-alpha. SimVX publishes development releases only (0.0.0.devN) and is under active development; the API changes between builds. Once stable versions ship to PyPI, development builds continue on pypi.simvx.com.

Install

pip install --pre simvx                    # the whole engine (recommended)
pip install --pre simvx-textures-basis     # the transcoder alone; it needs only cffi

Latest development build: add --extra-index-url https://pypi.simvx.com/.

Use

Nothing to configure: simvx-graphics uses it to load a UASTC .ktx2 texture, and simvx cook uses it to transcode one ahead of shipping:

simvx cook hero.ktx2 -o cooked/

Without it loading a UASTC texture raises ValueError and simvx cook copies the file unchanged. Textures already in an explicit block format load without it.

Use it directly

The package needs nothing from the engine. Each function takes one mip level's packed UASTC blocks (16 bytes per 4x4 block) with its size in texels, and returns the transcoded blocks:

from simvx.textures.basis import is_available, transcode_uastc_to_bc7

uastc = bytes(16 * 4)  # one 8x8 level: four 4x4 blocks, here all zero
if is_available():
    bc7 = transcode_uastc_to_bc7(uastc, 8, 8)

transcode_uastc_to_astc4x4 and transcode_uastc_to_etc2 take the same arguments, behind astc_available() and etc2_available(). A level of the wrong size raises ValueError.

Platforms: wheels for Linux x86_64 and aarch64, Windows x86_64, and macOS x86_64 and arm64; only Linux x86_64 is tested. The library is loaded through cffi's ABI mode and the wheel is tagged py3-none-<platform>, so one wheel per platform serves every CPython 3.14 build, free-threaded included.

Documentation · Source · Licence: AGPL-3.0-or-later with Additional Terms, including the Game-Distribution Exception. Vendored: basis_universal (Apache-2.0).