v4.4.2

[MarkCallow]

Notice

v4.4.2 is an emergency release that replaces v4.4.1 which has been withdrawn. It
fixes the version number in the release assets. There are no other changes
compared to v4.4.1.

Summary

• ktxTexture2_DecodeAstc now exposed in libktx_read on all platforms and in
  the JS bindings.
• ktx info can now show info about KTX v1 files. It and the underlying libktx
  function now display GL type and format token names instead of hex values.
• Many bugs and robustness issues have been fixed. Many of these address changes
  in CI runner images and the latest compilers.
• ASTC encoder updated to 5.3.0.
• LodePNG updated to 20250506.
• Building with Visual Studio 2019 is no longer supported.

The legacy tools will be removed in Release 4.5. Adjust your workflows accordingly.

New Features in v4.4.2

libktx functions

• ktxTexture2_DecodeAstc, which decodes an ASTC format texture to an
  uncompressed format, is now available in libktx_read on all platforms and in
  both the libktx and libktx_read JS bindings.
• ktxPrintKTX1InfoTextForStream, which prints information about a KTX v1 file
  and was previously internal, is now exposed.

Notable Fixes in v4.4.2

• A bug in mipmap generation in ktx create that led to sRGB images being
  resampled without first decoding to linear has been fixed. If you have affected
  KTX files you should regenerate your textures from their source images.
• libktx_read no longer includes the ASTC encode functions, only the decode
  functions.
• A bug that caused a hang in ktx create, when the source image is an RGB PNG
  file with an sBIT chunk and an alpha component is being added to the texture
  being created, has been fixed.

Known Issues

• Files deflated with zlib using libktx compiled with GCC and run on x86_64 may not be bit-identical with those using libktx compiled with GCC and run on arm64.

• Users making Basis Universal encoded or GPU block compressed textures for WebGL must be aware of WebGL restrictions with regard to texture size and may need to resize input images appropriately before using the ktx create tool, or use the --resize feature to produce an appropriately sized texture. In general, the dimensions of block compressed textures must be a multiple of the block size in WebGL and for WebGL 1.0 textures must have power-of-two dimensions. Additional portability restrictions apply for glTF per the KHR_texture_basisu extension which can be verified using the --gltf-basisu command-line option of ktx validate.

• Basis Universal encoding results (both ETC1S/LZ and UASTC) are non-deterministic across platforms. Results are valid but level sizes and data will differ slightly. See issue #60 in the basis_universal repository.

• UASTC RDO results differ from run to run unless multi-threading or RDO multi-threading is disabled. In toktx use --threads 1 for the former or --uastc_rdo_m for the latter. As with the preceeding issue results are valid but level sizes will differ slightly. See issue #151 in the basis_universal repository.

• Neither the Vulkan nor GL loaders support depth/stencil textures.

Changes since v4.4.0 (by part)

libktx

• 4.4.1 release prep (4.4.1 release prep #1063) (0b10eb1) (@MarkCallow)

• Add v1 support to ktx info (Add v1 support to ktx info #1060) (3cd9e34) (@MarkCallow)

• Remove mentions of retired edgewise-consulting.com. (Remove mentions of retired edgewise-consulting.com. #1058) (0306d6a) (@MarkCallow)

• Export ktxTexture2_DecodeAstc in JS bindings (Export ktxTexture2_DecodeAstc in JS bindings #1034) (64a6900) (@MarkCallow)

• Restore rotted bits: update vcpkg caching and pyktx to latest Python (Restore rotted bits: update vcpkg caching and pyktx to latest Python #1033) (f753fca) (@MarkCallow)

• Fix for Emscripten 4.0.9 (Fix for Emscripten 4.0.9 #1026) (1a98376) (@MarkCallow)

• Fix memory leaks. (Fix memory leaks. #1007) (504b962) (@MarkCallow)

Tools

• Add v1 support to ktx info (Add v1 support to ktx info #1060) (3cd9e34) (@MarkCallow)

• Remove mentions of retired edgewise-consulting.com. (Remove mentions of retired edgewise-consulting.com. #1058) (0306d6a) (@MarkCallow)

• Document that --generated-mipmap can't be used with --raw. (Document that --generated-mipmap can't be used with --raw. #1057) (1d7d444) (@MarkCallow)

• Update fmt to latest release (v11.2) (Update fmt to latest release (v11.2) #1056) (f5654c2) (@MarkCallow)

• Fix hang when adding alpha and PNG input has sBIT chunk. (Fix hang when adding alpha and PNG input has sBIT chunk. #1054) (d9a0c2b) (@MarkCallow)

• Set color space in input image prior to resample. (Set color space in input image prior to resample. #1051) (1daca0c) (@MarkCallow)

• Use relative rpaths to find installed library on macOS (Use relative rpaths to find installed library on macOS #1046) (d47320c) (@MarkCallow)

• Shut up warnings clang with libstdc++ emits about non-virtual destructors (Shut up warnings clang with libstdc++ emits about non-virtual destructors #1012) (fbb5412) (@DanielGibson)

• Fix CLI error handling for --normalize. (Fix CLI error handling for --normalize. #1016) (17d2062) (@MarkCallow)

• Update LodePNG to version 20241228, (Update LodePNG to version 20241228, #1015) (6d1fc82) (@MarkCallow)

JS Bindings

• Export ktxTexture2_DecodeAstc in JS bindings (Export ktxTexture2_DecodeAstc in JS bindings #1034) (64a6900) (@MarkCallow)

• Fix for Emscripten 4.0.9 (Fix for Emscripten 4.0.9 #1026) (1a98376) (@MarkCallow)

Java Bindings

• Use relative rpaths to find installed library on macOS (Use relative rpaths to find installed library on macOS #1046) (d47320c) (@MarkCallow)

Python Bindings

• Restore rotted bits: update vcpkg caching and pyktx to latest Python (Restore rotted bits: update vcpkg caching and pyktx to latest Python #1033) (f753fca) (@MarkCallow)

• Add option to use virtual environment for Python. (Add option to use virtual environment for Python. #1029) (b167e96) (@MarkCallow)

• Bump setuptools from 70.0.0 to 78.1.1 in /interface/python_binding (Bump setuptools from 70.0.0 to 78.1.1 in /interface/python_binding #1025) (94d0c3a) (@dependabot[bot])

• Fix python deprecation warning. (Fix python deprecation warning. #1018) (dac48df) (@MarkCallow)

External Package Dependencies

• Remove mentions of retired edgewise-consulting.com. (Remove mentions of retired edgewise-consulting.com. #1058) (0306d6a) (@MarkCallow)

• Update fmt to latest release (v11.2) (Update fmt to latest release (v11.2) #1056) (f5654c2) (@MarkCallow)

• Migrate loadtest apps to SDL3 (Migrate loadtest apps to SDL3 #1055) (443e122) (@MarkCallow)

• Update ASTC encoder to 5.3.0 (Update ASTC encoder to 5.3.0 #1036) (f6f0b9a) (@MarkCallow)

• Update lodepng to version 20250506 (Update lodepng to version 20250506 #1035) (f9c7338) (@MarkCallow)

• GCC14/C++23 compatibility fix (GCC14/C++23 compatibility fix #1014) (f3f6b3b) (@alexge50)

• Update LodePNG to version 20241228, (Update LodePNG to version 20241228, #1015) (6d1fc82) (@MarkCallow)

Tests

• Add v1 support to ktx info (Add v1 support to ktx info #1060) (3cd9e34) (@MarkCallow)

• Remove mentions of retired edgewise-consulting.com. (Remove mentions of retired edgewise-consulting.com. #1058) (0306d6a) (@MarkCallow)

• Update CTS ref to merged tests. (65b0031) (@MarkCallow)

• Document that --generated-mipmap can't be used with --raw. (Document that --generated-mipmap can't be used with --raw. #1057) (1d7d444) (@MarkCallow)

• Update fmt to latest release (v11.2) (Update fmt to latest release (v11.2) #1056) (f5654c2) (@MarkCallow)

• Migrate loadtest apps to SDL3 (Migrate loadtest apps to SDL3 #1055) (443e122) (@MarkCallow)

• Fix hang when adding alpha and PNG input has sBIT chunk. (Fix hang when adding alpha and PNG input has sBIT chunk. #1054) (d9a0c2b) (@MarkCallow)

• Set color space in input image prior to resample. (Set color space in input image prior to resample. #1051) (1daca0c) (@MarkCallow)

• Use relative rpaths to find installed library on macOS (Use relative rpaths to find installed library on macOS #1046) (d47320c) (@MarkCallow)

• Clarify platforms where unit tests not supported. (Clarify platforms where unit tests not supported. #1040) (f9f3694) (@MarkCallow)

• Minor build fixes (Minor build fixes #1039) (8dfb895) (@MarkCallow)

• Update for Vulkan SDK 1.4.313. (Update for Vulkan SDK 1.4.313. #1037) (d72218c) (@MarkCallow)

• Export ktxTexture2_DecodeAstc in JS bindings (Export ktxTexture2_DecodeAstc in JS bindings #1034) (64a6900) (@MarkCallow)

• Restore rotted bits: update vcpkg caching and pyktx to latest Python (Restore rotted bits: update vcpkg caching and pyktx to latest Python #1033) (f753fca) (@MarkCallow)

• Fix handling of multiple files with spaces in names. (Fix handling of multiple files with spaces in names. #1030) (b2f4da2) (@MarkCallow)

• Update CTS ref for merged test updates. (b9218bc) (@MarkCallow)

• Fix CLI error handling for --normalize. (Fix CLI error handling for --normalize. #1016) (17d2062) (@MarkCallow)

• Linux and MacOS workflows (Linux and MacOS workflows #1004) (520dc8f) (@MathiasMagnus)

Build Scripts and CMake files

• Add force-fetch-provoking-tag-annotation workaround (e5c085b) (@MarkCallow)

• Add options. (16a24e0) (@MarkCallow)

• Add v1 support to ktx info (Add v1 support to ktx info #1060) (3cd9e34) (@MarkCallow)

• Migrate loadtest apps to SDL3 (Migrate loadtest apps to SDL3 #1055) (443e122) (@MarkCallow)

• Fix hang when adding alpha and PNG input has sBIT chunk. (Fix hang when adding alpha and PNG input has sBIT chunk. #1054) (d9a0c2b) (@MarkCallow)

• Use relative rpaths to find installed library on macOS (Use relative rpaths to find installed library on macOS #1046) (d47320c) (@MarkCallow)

• Clarify platforms where unit tests not supported. (Clarify platforms where unit tests not supported. #1040) (f9f3694) (@MarkCallow)

• Minor build fixes (Minor build fixes #1039) (8dfb895) (@MarkCallow)

• Update for Vulkan SDK 1.4.313. (Update for Vulkan SDK 1.4.313. #1037) (d72218c) (@MarkCallow)

• Export ktxTexture2_DecodeAstc in JS bindings (Export ktxTexture2_DecodeAstc in JS bindings #1034) (64a6900) (@MarkCallow)

• Restore rotted bits: update vcpkg caching and pyktx to latest Python (Restore rotted bits: update vcpkg caching and pyktx to latest Python #1033) (f753fca) (@MarkCallow)

• Add option to use virtual environment for Python. (Add option to use virtual environment for Python. #1029) (b167e96) (@MarkCallow)

• Fix: Install graphviz if FEATURE_DOCS ON (Fix: Install graphviz if FEATURE_DOCS ON #1028) (e691019) (@MarkCallow)

• Fix for Emscripten 4.0.9 (Fix for Emscripten 4.0.9 #1026) (1a98376) (@MarkCallow)

• Enable use of Ninja Multi-Config generator for Linux builds (Enable use of Ninja Multi-Config generator for Linux builds #1017) (1618780) (@MarkCallow)

• Update LodePNG to version 20241228, (Update LodePNG to version 20241228, #1015) (6d1fc82) (@MarkCallow)

• Fix issues in CMakeLists.txt (see Issues in the CMakeLists.txt #996) (Fix issues in CMakeLists.txt (see #996) #998) (c033ac8) (@DanielGibson)

• Linux and MacOS workflows (Linux and MacOS workflows #1004) (520dc8f) (@MathiasMagnus)

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This discussion was created from the release v4.4.2.