Awesome

Shader Compiler

A command line tool that compiles GLSL shaders to SPIRV, and optimizes them using glslang-zig.

Remap is also supported (results in better compression), SPIRV is validated before results are written.

Usage

Note that the initial compile will take quite while as it's building the shader C++ implementation of the shader compiler. Once this finishes it will be cached.

Example usage:

zig build run -- --target Vulkan-1.3 --optimize-perf input.glsl output.spv

Example usage from Zig's build system:

const compile_shader = b.addRunArtifact(shader_compiler_exe);
compile_shader.addArgs(&.{
    "--target", "Vulkan-1.3",
});
switch (optimize) {
    .Debug => compile_shader.addArgs(&.{
        "--robust-access",
    }),
    .ReleaseSafe => compile_shader.addArgs(&.{
        "--optimize-perf",
        "--robust-access",
    }),
    .ReleaseFast => compile_shader.addArgs(&.{
        "--optimize-perf",
    }),
    .ReleaseSmall => compile_shader.addArgs(&.{
        "--optimize-perf",
        "--optimize-small",
    }),
}
compile_shader.addFileArg(b.path(path));
return compile_shader.addOutputFileArg("compiled.spv");

GL_ARB_shading_language_include

glslang supports #include via the GL_ARB_shading_language_include extension. You can enable it in your shaders like this:

#extension GL_ARB_shading_language_include : require

You will also need to specify at least one include path via --include-path. Multiple can be specified by passing the arg more than once. If calling via Zig's build system, use '--write-deps' for proper caching behavior.

Command line:

zig build run -- --target Vulkan-1.3 --include-path include shader.vert shader.spv

Zig build system:

compile_shader.addArg("--include-path");
compile_shader.addDirectoryArg(b.path("include"));
compile_shader.addArg("--write-deps");
_ = compile_shader.addDepFileOutputArg("deps.d");

You can now include files in your shaders:

#include "foo.glsl"

For details on inclusion syntax and path resolution, see the extension specification.