Crate vulkano_shaders

The procedural macro for vulkano's shader system. Manages the compile-time compilation of GLSL into SPIR-V and generation of assosciated rust code.

Basic usage

mod vs {
    vulkano_shaders::shader!{
        ty: "vertex",
        src: "
#version 450

layout(location = 0) in vec3 position;

void main() {
    gl_Position = vec4(position, 1.0);
}"
    }
}

Details

If you want to take a look at what the macro generates, your best options are to either read through the code that handles the generation (the reflect function in the vulkano-shaders crate) or use a tool such as cargo-expand to view the expansion of the macro in your own code. It is unfortunately not possible to provide a generated_example module like some normal macro crates do since derive macros cannot be used from the crate they are declared in. On the other hand, if you are looking for a high-level overview, you can see the below section.

Generated code overview

The macro generates the following items of interest:

• The Shader struct. This contains a single field, shader, which is an Arc<ShaderModule>.
• The Shader::load constructor. This method takes an Arc<Device>, calls ShaderModule::new with the passed-in device and the shader data provided via the macro, and returns Result<Shader, OomError>. Before doing so, it loops through every capability instruction in the shader data, verifying that the passed-in Device has the appropriate features enabled. This function currently panics if a feature required by the shader is not enabled on the device. At some point in the future it will return an error instead.
• The Shader::module method. This method simply returns a reference to the Arc<ShaderModule> contained within the shader field of the Shader struct.
• Methods for each entry point of the shader module. These construct and return the various entry point structs that can be found in the vulkano::pipeline::shader module.
• A Rust struct translated from each struct contained in the shader data.
• The Layout newtype. This contains a ShaderStages struct. An implementation of PipelineLayoutDesc is also generated for the newtype.
• The SpecializationConstants struct. This contains a field for every specialization constant found in the shader data. Implementations of Default and SpecializationConstants are also generated for the struct.

All of these generated items will be accessed through the module specified by mod_name: foo If you wanted to store the Shader in a struct of your own, you could do something like this:

// various use statements
// `vertex_shader` module with shader derive

pub struct Shaders {
    pub vs: vs::Shader
}

impl Shaders {
    pub fn load(device: Arc<Device>) -> Result<Self, OomError> {
        Ok(Self {
            vs: vs::Shader::load(device)?,
        })
    }
}

Options

The options available are in the form of the following attributes:

ty: "..."

This defines what shader type the given GLSL source will be compiled into. The type can be any of the following:

• vertex
• fragment
• geometry
• tess_ctrl
• tess_eval
• compute

For details on what these shader types mean, see Vulkano's documentation.

src: "..."

Provides the raw GLSL source to be compiled in the form of a string. Cannot be used in conjunction with the path field.

path: "..."

Provides the path to the GLSL source to be compiled, relative to Cargo.toml. Cannot be used in conjunction with the src field.

include: ["...", "...", ..., "..."]

Specifies the standard include directories to be searched through when using the #include <...> directive within a shader source. If path was specified, relative paths can also be used (#include "..."), without the need to specify one or more standard include directories. Relative paths are relative to the directory, which contains the source file the #include "..." directive is declared in.

dump: true

The crate fails to compile but prints the generated rust code to stdout.

Macros

shader