flutter_gpu_shaders

• Track the impellerc binary as a build input, so bundles rebuild whenever the engine artifacts change.
• Write an engine stamp beside each bundle, so a shared pub-cache bundle rewritten by another project (or Flutter SDK) triggers a rebuild instead of shipping a wrong-engine bundle.
• Recover depfile dependency paths containing spaces (impellerc writes them unescaped); a split path declared a nonexistent dependency, which made the hook re-run on every build for SDKs under paths like Application Support.

• Track the impellerc binary as a build input, so bundles rebuild whenever the engine artifacts change.
• Write an engine stamp beside each bundle, so a shared pub-cache bundle rewritten by another project (or Flutter SDK) triggers a rebuild instead of shipping a wrong-engine bundle.
• Recover depfile dependency paths containing spaces (impellerc writes them unescaped); a split path declared a nonexistent dependency, which made the hook re-run on every build for SDKs under paths like Application Support.

• Added a glesLanguageVersion option to buildShaderBundleJson (and shaderBundleImpellercArguments), forwarded to impellerc as --gles-language-version. Setting 300 emits #version 300 es OpenGL ES shaders, where explicit-LOD sampling and derivatives are core rather than extension-gated.
• findImpellerC now also probes the linux-arm64 and windows-arm64 engine artifact directories; the previous x64-only list failed on Linux arm64 hosts.

• Added a glesLanguageVersion option to buildShaderBundleJson (and shaderBundleImpellercArguments), forwarded to impellerc as --gles-language-version. Setting 300 emits #version 300 es OpenGL ES shaders, where explicit-LOD sampling and derivatives are core rather than extension-gated.
• findImpellerC now also probes the linux-arm64 and windows-arm64 engine artifact directories; the previous x64-only list failed on Linux arm64 hosts.

• Fixed dependency tracking that made the build hook re-run on every build. Manifest file entries are now resolved against the package root (matching how impellerc resolves them) instead of the manifest's directory, which had produced doubled, non-existent paths for manifests in a subdirectory.
• Generated shader sources written under the package's build/ directory are no longer declared as build dependencies; depending on a regenerated output made the hook perpetually out of date. Declare the real sources that produce them instead.
• Breaking: collectShaderBundleDependencies now requires a packageRoot argument (used to resolve manifest file paths). Most consumers use buildShaderBundleJson, whose signature is unchanged.

• Fixed dependency tracking that made the build hook re-run on every build. Manifest file entries are now resolved against the package root (matching how impellerc resolves them) instead of the manifest's directory, which had produced doubled, non-existent paths for manifests in a subdirectory.
• Generated shader sources written under the package's build/ directory are no longer declared as build dependencies; depending on a regenerated output made the hook perpetually out of date. Declare the real sources that produce them instead.
• Breaking: collectShaderBundleDependencies now requires a packageRoot argument (used to resolve manifest file paths). Most consumers use buildShaderBundleJson, whose signature is unchanged.

Changes

• Added optional Dart DataAssets registration for generated shader bundles via ShaderBundleAssetMode.
• dataAssetsIfAvailable registers the generated .shaderbundle with the Flutter asset bundle when supported and falls back to legacy file output otherwise.
• buildShaderBundleJson now returns ShaderBundleBuildResult, including legacy and DataAsset asset keys when available.

Published to pub.dev: https://pub.dev/packages/flutter_gpu_shaders/versions/0.4.5

• Added optional Dart DataAssets registration for shader bundles via ShaderBundleAssetMode. The default remains legacy file output under build/shaderbundles/, while dataAssetsIfAvailable registers the generated .shaderbundle with the Flutter asset bundle when supported and falls back otherwise.
• buildShaderBundleJson now returns ShaderBundleBuildResult, including the legacy asset key and DataAsset/Flutter asset keys when a DataAsset is emitted.

• buildShaderBundleJson now consumes impellerc depfiles when the resolved compiler advertises --depfile support. This lets newer Flutter SDKs track transitive shader #include dependencies while preserving the existing manifest dependency scan for older impellerc builds that do not support the flag or do not emit a depfile in --shader-bundle mode.
• buildShaderBundleJson accepts an includeDirectories parameter: extra directories appended to impellerc's #include search path, after the manifest directory and the bundled shader_lib. This lets a build hook compile shaders that #include reusable GLSL shipped by another package, by resolving that package's shader directory and passing it through. Files resolved this way are not auto-declared as build dependencies; declare them via the build output if edits to them should retrigger the build.
• New shaderBundleImpellercArguments(...) helper returns the exact impellerc argument list, exposed for inspection from custom build hooks and tests.

• findImpellerC now also honors a runtime IMPELLERC environment variable in addition to the compile-time define. flutter_tools populates this for build hook subprocesses (https://github.com/flutter/flutter/pull/186300), including the --local-engine case where the locally built impellerc should be used in preference to the SDK cache. Compile-time define takes precedence; runtime env var is checked next; otherwise the existing SDK cache lookup runs.

• Documentation: update README.md and buildShaderBundleJson dartdoc to reflect the 0.4.0 migration (drop the obsolete flutter config --enable-native-assets step, swap the import, and rename buildConfig: → buildInput: to match the parameter name introduced in 0.3.0). No code changes.

• Migrate from native_assets_cli (discontinued) to hooks 1.0. Build hook authors must now import 'package:hooks/hooks.dart'; instead of package:native_assets_cli/native_assets_cli.dart.
• Bump SDK constraint to ^3.7.0 (matches hooks 1.0 requirements).

• Update to native_assets_cli to 0.13.0. (https://github.com/bdero/flutter_gpu_shaders/issues/6) Breaking: BuildConfig is now BuildInput

• Update to native_assets_cli 0.9.0. Breaking: BuildOutput is now BuildOutputBuilder

• Pin native_assets_cli to <0.9.0. (https://github.com/bdero/flutter_gpu_shaders/issues/3)

• Relax native_assets_cli dependency pin.

• Fix SDK path resolution for puro users.

• Fix working directory for impellerc invocation.

• Add buildShaderBundleJson build hook utility.
• Document usage instructions in the readme.