Amber is a multi-API shader test framework.
Amber lets you capture and communicate shader bugs with the fluidity and ease of a scripting flow:
Amber is influenced by Talvos and VkRunner. The VkScript syntax matches the format used by VkRunner.
This is not an officially supported Google product.
Working with Amber involves writing input test files. Some example files can be see in the tests/cases folder.
The main input format is Amberscript. New features are added to AmberScript as Amber is enhanced. This is the preferred format in which new script files are written.
SHADER vertex vtex_shader PASSTHROUGH SHADER fragment frag_shader GLSL #version 430 layout(location = 0) in vec4 color_in; layout(location = 0) out vec4 color_out; void main() { color_out = color_in; } END BUFFER img_buf FORMAT B8G8R8A8_UNORM PIPELINE graphics my_pipeline ATTACH vtex_shader ATTACH frag_shader FRAMEBUFFER_SIZE 256 256 BIND BUFFER img_buf AS color LOCATION 0 END CLEAR my_pipeline EXPECT img_buf IDX 0 0 SIZE 256 256 EQ_RGBA 0 0 0 0
The VkScript format is supported for historic reasons. It is based off, and very closely matches, the format accepted by VkRunner. There are no new features being added to VkScript, it is for historical use.
[require]
VK_KHR_get_physical_device_properties2
[vertex shader passthrough]
[fragment shader]
#version 430
layout(location = 0) in vec4 color_in;
layout(location = 0) out vec4 color_out;
void main() {
color_out = color_in;
}
[test]
clear
relative probe rect rgba (0.0, 0.0, 1.0, 1.0) (0, 0, 0, 0)
git clone https://github.com/google/amber.git cd amber ./tools/git-sync-deps mkdir -p out/Debug cd out/Debug cmake -GNinja ../.. ninja
Alternatives:
-DAMBER_ENABLE_SHARED_CRT. This will cause Amber to be built with /MD for release builds or /MDd for debug builds.ANDROID_PLATFORM and ANDROID_BUILD_TOOL_VERSION in tools/build-amber-sample.sh.export ANDROID_SDK_HOME=path/to/Android/SDK in your shell.export ANDROID_NDK_HOME=path/to/Android/NDK in your shell.keytool command and set up KEY_STORE_PATH env variable for the KeyStore file path../tools/build-amber-sample.sh [build output directory path].It is possible to obtain a plain executable for Android, as opposed to an APK, with the following:
git clone https://github.com/google/amber.git
cd amber
./tools/git-sync-deps
./tools/update_build_version.py . samples/ third_party/
./tools/update_vk_wrappers.py . .
mkdir build
cd build
mkdir app
mkdir libs
${ANDROID_NDK_HOME}/ndk-build -C ../samples NDK_PROJECT_PATH=. NDK_LIBS_OUT=`pwd`/libs NDK_APP_OUT=`pwd`/app
The list of target ABIs can be configured in samples/jni/Application.mk by editing the APP_ABI entry:
APP_ABI := arm64-v8a armeabi-v7a x86 x86_64
The resulting executable will be produced as build/app/local/<abi>/amber_ndk. This executable can be run via the adb shell on your device, e.g. under /data/local/tmp (/sdcard is generally not suitable because it is mounted with a non-executable flag). Also, vulkan layers may not be available to this executable as it is not an app, so make sure to use the -d flag to disable Vulkan layers:
adb push build/app/local/<abi>/amber_ndk /data/local/tmp adb shell # Now on device shell cd /data/local/tmp ./amber_ndk -d <shader-test-files>
The components which build up Amber can be enabled or disabled as needed. Any option with _SKIP_ in the name is on by default, any with _USE_ is off by default.
The available flags which can be defined are:
cmake -DAMBER_SKIP_TESTS=True -DAMBER_SKIP_SPIRV_TOOLS=True -GNinja ../..
DXC can be enabled in Amber by adding the -DAMBER_USE_DXC=true flag when running cmake.
There are a number of build bots to verify Amber continues to compile and run on the various targets. Due to bot limitations, the integration tests are not being run on the bots, just the unit tests.
Amber is designed to run against different graphics APIs. Amber will build if no graphics API is found, but will only allow verifying the syntax of the amber script files.
Currently the Vulkan and Dawn graphics APIs are supported.
A Vulkan implementation is found by CMake in the following priority order:
If AMBER_USE_LOCAL_VULKAN is enable the headers, loader and layers will be built locally and not found on the system.
If an enclosing CMake project includes the Vulkan-Headers CMake project, then headers will be picked up from there.
In this case the CMake variable Vulkan_LIBRARIES can name the Vulkan library, or a default of vulkan will be used.
If you have CMake 3.7 or later, then the Vulkan implementation will be found from a Vulkan SDK as published by LunarG.
Environment variables:
VULKAN_SDK should point to the platform-specific SDK directory that contains the include and lib directories.VK_ICD_FILENAMES should point to the ICD JSON file.VK_LAYER_PATH should point to the explicit_layer.d folder.LD_LIBRARY_PATH must contain the $VULKAN_SDK/lib/ folder for the validation libraries.export VULKAN_SDK=$HOME/vulkan-macos-1.1.85.0/macOS export VK_ICD_FILENAMES=$VULKAN_SDK/etc/vulkan/icd.d/MoltenVK_icd.json export VK_LAYER_PATH=$VULKAN_SDK/etc/vulkan/explicit_layer.d export LD_LIBRARY_PATH=$VULKAN_SDK/lib:$LD_LIBRARY_PATH
We assume you have built Dawn from source, and have access to both the source and build trees. To build a Dawn backend for Amber, set the following CMake variables when configuring Amber:
Dawn_INCLUDE_DIR: The directory containing dawn/dawn_export.h (in the source tree).Dawn_GEN_INCLUDE_DIR: The directory containing generated header dawn/dawncpp.h (in the build output tree).Dawn_LIBRARY_DIR: The directory containing the dawn_native library (in the build output tree).The build will generate an out/Debug/amber executable which can be used to run amber scripts. The script can be used as out/Debug/amber <path to amber file>. Where, currently, the amber file is in the VkScript format.
out/Debug/amber tests/cases/clear.amber
The sample app returns a value of 0 on success or non-zero on error. Any issues encountered should be displayed on the console.
By default, out/Debug/amber supports saving the output image into '.png' file. You can disable this by passing -DAMBER_SKIP_LODEPNG=true to cmake.
The image_diff program will also be created. This allows comparing two images using the Amber buffer comparison methods.
Please see the CONTRIBUTING and CODE_OF_CONDUCT files on how to contribute to Amber.
SwiftShader if installed it can be used by by exporting the VK_ICD_FILENAMES environment variable and using it directly. If SwiftShader is not installed it can be built with Amber by setting AMBER_ENABLE_SWIFTSHADER during the configure step of CMake.
mkdir out/sw cd out/sw cmake -GNinja -DAMBER_ENABLE_SWIFTSHADER=TRUE ../.. ninja export VK_ICD_FILENAMES=$PWD/Linux/vk_swiftshader_icd.json ./amber -d -V # Should see SwiftShader listed as device ./amber -d ../../tests/cases/clear.amber