GLSL compilation

Before you can use your shaders, you need to compile the glsl code to Spirv binary code. Only Spirv can be uploaded to the GPU. LunarG (creator of the Vulkan SDK) provides use with a command line executable to do exactly that: glslangValidator.exe Google also provides a compiler: glslc.exe You can use either of them, so far both seems to work well and are included with the Vulkan SDK in the bin directory. In MiniEngine, we use glslc.exe.

Prerequisites

• First, you need the Vulkan SDK installed on your computer. You can download it here: https://www.lunarg.com/vulkan-sdk/
• Be sure the environment variable 'VULKAN_SDK' is correctly configured and points to your Vulkan SDK root folder (ex: C:\VulkanSDK\1.3.261.1)

Manual compilation with glslangValidator.exe

Commandline:

glslangValidator.exe -V [sourcefile] -o [outputfile]

Exemple:

glslangValidator.exe -V shader-simple.vert -o shader-simple.vert.spv

Important: the extension of the sourcefile is important:

Extension	Stage
.vert	vertex
.frag	fragment
.vert	vertex
.tesc	tesselation control
.tese	tesselation evaluation
.geom	geometry
.comp	mesh
.rgen	ray generation
.rint	ray intersection
.rahit	ray any hit
.rahit	ray any hit
.rchit	ray closest hit
.rmiss	ray miss
.rcall	ray callable
.glsl	.vert.glsl, .tesc.glsl, ..., .comp.glsl compound suffixes
.hlsl	.vert.hlsl, .tesc.hlsl, ..., .comp.hlsl compound suffixes

Manual compilation with glslc.exe

Commandline:

glslc.exe [sourcefile] -o [outputfile]

Exemple:

glslc.exe shader-simple.vert -o shader-simple.vert.spv

Important: the extension of the sourcefile is important:

Extension	Stage
.vert	vertex
.frag	fragment
.vert	vertex
.tesc	tesselation control
.tese	tesselation evaluation
.geom	geometry
.comp	compute

Compilation from C#

MiniEngime providers the 'ShaderCompiler' class to encapsulate the call to glslc.exe.

The method Compile takes the shader string code and the stage in parameters and returns the spirv binary code. If some compilation errors occur, an Exception will be throwed.

Exemple:

using MiniEngine.Drivers.Vulkan;

string code = @"#version 450

layout(location = 0) out vec4 outColor;

void main() {
    outColor = vec4(1, 1, 1, 1);
}";

byte[] spirv = ShaderCompiler.Compile(code, ShaderStageFlags.Fragment);