-Also see the Khronos landing page for glslang as a reference front end:
+# News
-https://www.khronos.org/opengles/sdk/tools/Reference-Compiler/
+1. Visual Studio 2013 is no longer supported
+
+ [As scheduled](https://github.com/KhronosGroup/glslang/blob/9eef54b2513ca6b40b47b07d24f453848b65c0df/README.md#planned-deprecationsremovals),
+Microsoft Visual Studio 2013 is no longer officially supported. \
+ Please upgrade to at least Visual Studio 2015.
+
+2. The versioning scheme is being improved, and you might notice some differences. This is currently WIP, but will be coming soon. See, for example, PR #2277.
-The above page includes where to get binaries, and is kept up to date
-regarding the feature level of glslang.
+3. If you get a new **compilation error due to a missing header**, it might be caused by this planned removal:
-glslang
-=======
+**SPIRV Folder, 1-May, 2020.** Glslang, when installed through CMake,
+will install a `SPIRV` folder into `${CMAKE_INSTALL_INCLUDEDIR}`.
+This `SPIRV` folder is being moved to `glslang/SPIRV`.
+During the transition the `SPIRV` folder will be installed into both locations.
+The old install of `SPIRV/` will be removed as a CMake install target no sooner than May 1, 2020.
+See issue #1964.
-[](https://travis-ci.org/KhronosGroup/glslang)
-[](https://ci.appveyor.com/project/Khronoswebmaster/glslang/branch/master)
+If people are only using this location to get spirv.hpp, I recommend they get that from [SPIRV-Headers](https://github.com/KhronosGroup/SPIRV-Headers) instead.
-An OpenGL and OpenGL ES shader front end and validator.
+[](https://ci.appveyor.com/project/Khronoswebmaster/glslang/branch/master)
+
+
+# Glslang Components and Status
There are several components:
-1. A GLSL/ESSL front-end for reference validation and translation of GLSL/ESSL into an AST.
+### Reference Validator and GLSL/ESSL -> AST Front End
+
+An OpenGL GLSL and OpenGL|ES GLSL (ESSL) front-end for reference validation and translation of GLSL/ESSL into an internal abstract syntax tree (AST).
+
+**Status**: Virtually complete, with results carrying similar weight as the specifications.
+
+### HLSL -> AST Front End
+
+An HLSL front-end for translation of an approximation of HLSL to glslang's AST form.
+
+**Status**: Partially complete. Semantics are not reference quality and input is not validated.
+This is in contrast to the [DXC project](https://github.com/Microsoft/DirectXShaderCompiler), which receives a much larger investment and attempts to have definitive/reference-level semantics.
+
+See [issue 362](https://github.com/KhronosGroup/glslang/issues/362) and [issue 701](https://github.com/KhronosGroup/glslang/issues/701) for current status.
+
+### AST -> SPIR-V Back End
+
+Translates glslang's AST to the Khronos-specified SPIR-V intermediate language.
+
+**Status**: Virtually complete.
-2. An HLSL front-end for translation of a broad generic HLL into the AST. See [issue 362](https://github.com/KhronosGroup/glslang/issues/362) and [issue 701](https://github.com/KhronosGroup/glslang/issues/701) for current status.
+### Reflector
-3. A SPIR-V back end for translating the AST to SPIR-V.
+An API for getting reflection information from the AST, reflection types/variables/etc. from the HLL source (not the SPIR-V).
-4. A standalone wrapper, `glslangValidator`, that can be used as a command-line tool for the above.
+**Status**: There is a large amount of functionality present, but no specification/goal to measure completeness against. It is accurate for the input HLL and AST, but only approximate for what would later be emitted for SPIR-V.
-How to add a feature protected by a version/extension/stage/profile: See the
-comment in `glslang/MachineIndependent/Versions.cpp`.
+### Standalone Wrapper
+
+`glslangValidator` is command-line tool for accessing the functionality above.
+
+Status: Complete.
Tasks waiting to be done are documented as GitHub issues.
-Deprecations
-------------
+## Other References
+
+Also see the Khronos landing page for glslang as a reference front end:
+
+https://www.khronos.org/opengles/sdk/tools/Reference-Compiler/
+
+The above page, while not kept up to date, includes additional information regarding glslang as a reference validator.
-1. GLSLang, when installed through CMake, will install a `SPIRV` folder into
-`${CMAKE_INSTALL_INCLUDEDIR}`. This `SPIRV` folder is being moved to
-`glslang/SPIRV`. During the transition the `SPIRV` folder will be installed into
-both locations. The old install of `SPIRV/` will be removed as a CMake install
-target no sooner than May 1, 2020. See issue #1964.
+# How to Use Glslang
-Execution of Standalone Wrapper
--------------------------------
+## Execution of Standalone Wrapper
To use the standalone binary form, execute `glslangValidator`, and it will print
a usage statement. Basic operation is to give it a file containing a shader,
* `.frag` for a fragment shader
* `.comp` for a compute shader
-There is also a non-shader extension
+For ray tracing pipeline shaders:
+* `.rgen` for a ray generation shader
+* `.rint` for a ray intersection shader
+* `.rahit` for a ray any-hit shader
+* `.rchit` for a ray closest-hit shader
+* `.rmiss` for a ray miss shader
+* `.rcall` for a callable shader
+
+There is also a non-shader extension:
* `.conf` for a configuration file of limits, see usage statement for example
-Building
---------
+## Building (CMake)
Instead of building manually, you can also download the binaries for your
platform directly from the [master-tot release][master-tot-release] on GitHub.
### Dependencies
* A C++11 compiler.
- (For MSVS: 2015 is recommended, 2013 is fully supported/tested, and 2010 support is attempted, but not tested.)
+ (For MSVS: use 2015 or later.)
* [CMake][cmake]: for generating compilation targets.
* make: _Linux_, ninja is an alternative, if configured.
* [Python 3.x][python]: for executing SPIRV-Tools scripts. (Optional if not using SPIRV-Tools and the 'External' subdirectory does not exist.)
The following steps assume a Bash shell. On Windows, that could be the Git Bash
shell or some other shell of your choosing.
-#### 1) Check-Out this project
+#### 1) Check-Out this project
```bash
cd <parent of where you want glslang to be>
git clone https://github.com/google/googletest.git External/googletest
```
-If you want to use googletest with Visual Studio 2013, you also need to check out an older version:
+TEMPORARY NOTICE: additionally perform the following to avoid a current
+breakage in googletest:
```bash
-# to use googletest with Visual Studio 2013
cd External/googletest
-git checkout 440527a61e1c91188195f7de212c63c77e8f0a45
+git checkout 0c400f67fcf305869c5fb113dd296eca266c9725
cd ../..
```
# "Release" (for CMAKE_BUILD_TYPE) could also be "Debug" or "RelWithDebInfo"
```
+For building on Android:
+```bash
+cmake $SOURCE_DIR -G "Unix Makefiles" -DCMAKE_INSTALL_PREFIX="$(pwd)/install" -DANDROID_ABI=arm64-v8a -DCMAKE_BUILD_TYPE=Release -DANDROID_STL=c++_static -DANDROID_PLATFORM=android-24 -DCMAKE_SYSTEM_NAME=Android -DANDROID_TOOLCHAIN=clang -DANDROID_ARM_MODE=arm -DCMAKE_MAKE_PROGRAM=$ANDROID_NDK_HOME/prebuilt/linux-x86_64/bin/make -DCMAKE_TOOLCHAIN_FILE=$ANDROID_NDK_HOME/build/cmake/android.toolchain.cmake
+# If on Windows will be -DCMAKE_MAKE_PROGRAM=%ANDROID_NDK_HOME%\prebuilt\windows-x86_64\bin\make.exe
+# -G is needed for building on Windows
+# -DANDROID_ABI can also be armeabi-v7a for 32 bit
+```
+
For building on Windows:
```bash
If using MSVC, after running CMake to configure, use the
Configuration Manager to check the `INSTALL` project.
+### Building (GN)
+
+glslang can also be built with the [GN build system](https://gn.googlesource.com/gn/).
+
+#### 1) Install `depot_tools`
+
+Download [depot_tools.zip](https://storage.googleapis.com/chrome-infra/depot_tools.zip),
+extract to a directory, and add this directory to your `PATH`.
+
+#### 2) Synchronize dependencies and generate build files
+
+This only needs to be done once after updating `glslang`.
+
+With the current directory set to your `glslang` checkout, type:
+
+```bash
+./update_glslang_sources.py
+gclient sync --gclientfile=standalone.gclient
+gn gen out/Default
+```
+
+#### 3) Build
+
+With the current directory set to your `glslang` checkout, type:
+
+```bash
+cd out/Default
+ninja
+```
+
### If you need to change the GLSL grammar
The grammar in `glslang/MachineIndependent/glslang.y` has to be recompiled with
the web grammar subset (see more about the web subset in the next section).
### Building to WASM for the Web and Node
+### Building a standalone JS/WASM library for the Web and Node
Use the steps in [Build Steps](#build-steps), with the following notes/exceptions:
-* For building the web subset of core glslang:
- + execute `updateGrammar web` from the glslang subdirectory
- (or if using your own scripts, `m4` needs a `-DGLSLANG_WEB` argument)
- + set `-DENABLE_HLSL=OFF -DBUILD_TESTING=OFF -DENABLE_OPT=OFF -DINSTALL_GTEST=OFF`
- + turn on `-DENABLE_GLSLANG_WEB=ON`
- + optionally, for GLSL compilation error messages, turn on `-DENABLE_GLSLANG_WEB_DEVEL=ON`
* `emsdk` needs to be present in your executable search path, *PATH* for
- Bash-like environments
- + [Instructions located
- here](https://emscripten.org/docs/getting_started/downloads.html#sdk-download-and-install)
+ Bash-like environments:
+ + [Instructions located here](https://emscripten.org/docs/getting_started/downloads.html#sdk-download-and-install)
* Wrap cmake call: `emcmake cmake`
+* Set `-DBUILD_TESTING=OFF -DENABLE_OPT=OFF -DINSTALL_GTEST=OFF`.
+* Set `-DENABLE_HLSL=OFF` if HLSL is not needed.
+* For a standalone JS/WASM library, turn on `-DENABLE_GLSLANG_JS=ON`.
+* For building a minimum-size web subset of core glslang:
+ + turn on `-DENABLE_GLSLANG_WEBMIN=ON` (disables HLSL)
+ + execute `updateGrammar web` from the glslang subdirectory
+ (or if using your own scripts, `m4` needs a `-DGLSLANG_WEB` argument)
+ + optionally, for GLSL compilation error messages, turn on
+ `-DENABLE_GLSLANG_WEBMIN_DEVEL=ON`
* To get a fully minimized build, make sure to use `brotli` to compress the .js
and .wasm files
Example:
```sh
-emcmake cmake -DCMAKE_BUILD_TYPE=Release -DENABLE_GLSLANG_WEB=ON \
+emcmake cmake -DCMAKE_BUILD_TYPE=Release -DENABLE_GLSLANG_JS=ON \
-DENABLE_HLSL=OFF -DBUILD_TESTING=OFF -DENABLE_OPT=OFF -DINSTALL_GTEST=OFF ..
```
-Testing
--------
+## Building glslang - Using vcpkg
+
+You can download and install glslang using the [vcpkg](https://github.com/Microsoft/vcpkg) dependency manager:
+
+ git clone https://github.com/Microsoft/vcpkg.git
+ cd vcpkg
+ ./bootstrap-vcpkg.sh
+ ./vcpkg integrate install
+ ./vcpkg install glslang
+
+The glslang port in vcpkg is kept up to date by Microsoft team members and community contributors. If the version is out of date, please [create an issue or pull request](https://github.com/Microsoft/vcpkg) on the vcpkg repository.
+
+## Testing
Right now, there are two test harnesses existing in glslang: one is [Google
Test](gtests/), one is the [`runtests` script](Test/runtests). The former
`localtestlist` to list non-tracked tests. This is automatically read
by `runtests` and included in the `diff` and `bump` process.
-Programmatic Interfaces
------------------------
+## Programmatic Interfaces
Another piece of software can programmatically translate shaders to an AST
using one of two different interfaces:
In practice, `ShCompile()` takes shader strings, default version, and
warning/error and other options for controlling compilation.
-Basic Internal Operation
-------------------------
+### C Functional Interface (new)
+
+This interface is located `glslang_c_interface.h` and exposes functionality similar to the C++ interface. The following snippet is a complete example showing how to compile GLSL into SPIR-V 1.5 for Vulkan 1.2.
+
+```cxx
+std::vector<uint32_t> compileShaderToSPIRV_Vulkan(glslang_stage_t stage, const char* shaderSource, const char* fileName)
+{
+ const glslang_input_t input = {
+ .language = GLSLANG_SOURCE_GLSL,
+ .stage = stage,
+ .client = GLSLANG_CLIENT_VULKAN,
+ .client_version = GLSLANG_TARGET_VULKAN_1_2,
+ .target_language = GLSLANG_TARGET_SPV,
+ .target_language_version = GLSLANG_TARGET_SPV_1_5,
+ .code = shaderSource,
+ .default_version = 100,
+ .default_profile = GLSLANG_NO_PROFILE,
+ .force_default_version_and_profile = false,
+ .forward_compatible = false,
+ .messages = GLSLANG_MSG_DEFAULT_BIT,
+ .resource = reinterpret_cast<const glslang_resource_t*>(&glslang::DefaultTBuiltInResource),
+ };
+
+ glslang_shader_t* shader = glslang_shader_create(&input);
+
+ if (!glslang_shader_preprocess(shader, &input)) {
+ printf("GLSL preprocessing failed %s\n", fileName);
+ printf("%s\n", glslang_shader_get_info_log(shader));
+ printf("%s\n", glslang_shader_get_info_debug_log(shader));
+ printf("%s\n", input.code);
+ glslang_shader_delete(shader);
+ return std::vector<uint32_t>();
+ }
+
+ if (!glslang_shader_parse(shader, &input)) {
+ printf("GLSL parsing failed %s\n", fileName);
+ printf("%s\n", glslang_shader_get_info_log(shader));
+ printf("%s\n", glslang_shader_get_info_debug_log(shader));
+ printf("%s\n", glslang_shader_get_preprocessed_code(shader));
+ glslang_shader_delete(shader);
+ return std::vector<uint32_t>();
+ }
+
+ glslang_program_t* program = glslang_program_create();
+ glslang_program_add_shader(program, shader);
+
+ if (!glslang_program_link(program, GLSLANG_MSG_SPV_RULES_BIT | GLSLANG_MSG_VULKAN_RULES_BIT)) {
+ printf("GLSL linking failed %s\n", fileName);
+ printf("%s\n", glslang_program_get_info_log(program));
+ printf("%s\n", glslang_program_get_info_debug_log(program));
+ glslang_program_delete(program);
+ glslang_shader_delete(shader);
+ return std::vector<uint32_t>();
+ }
+
+ glslang_program_SPIRV_generate(program, stage);
+
+ std::vector<uint32_t> outShaderModule(glslang_program_SPIRV_get_size(program));
+ glslang_program_SPIRV_get(program, outShaderModule.data());
+
+ const char* spirv_messages = glslang_program_SPIRV_get_messages(program);
+ if (spirv_messages)
+ printf("(%s) %s\b", fileName, spirv_messages);
+
+ glslang_program_delete(program);
+ glslang_shader_delete(shader);
+
+ return outShaderModule;
+}
+```
+
+## Basic Internal Operation
* Initial lexical analysis is done by the preprocessor in
`MachineIndependent/Preprocessor`, and then refined by a GLSL scanner
- the object does not come from the pool, and you have to do normal
C++ memory management of what you `new`
+* Features can be protected by version/extension/stage/profile:
+ See the comment in `glslang/MachineIndependent/Versions.cpp`.
[cmake]: https://cmake.org/
[python]: https://www.python.org/
projects / platform / upstream / glslang.git / blobdiff