Slang Shader Engineer

int a[3];            // fixed size
int a[] = {1,2,3};  // inferred size
void f(int b[]) {}  // unsized parameter

struct MyData { int a; float b; }
// Custom constructor:
__init(int a_, float b_) { a = a_; b = b_; }

struct MaterialParams { float3 albedo; float metallic; float roughness; };
ParameterBlock<MaterialParams> gMaterial;
// Binds to a single descriptor table (D3D12) or descriptor set (Vulkan)

import foo;                  // imports foo.slang
__exported import foo;       // re-exports foo's declarations

interface ILight
{
    LightSample sample(float3 position);
    static int  getCount();               // static method in interface
    property int id { get; set; }        // property in interface
    int compute<T>(T val) where T : IBar; // generic method in interface
}

struct PointLight : ILight
{
    float3 position;
    LightSample sample(float3 hitPos) { ... }
    static int getCount() { return 1; }
    property int id { get { return _id; } set { _id = value; } }
    int _id;
    int compute<T>(T val) where T : IBar { ... }
}

struct MyType : IFoo, IBar { ... }

interface IFoo
{
    int getVal() { return 0; }  // default
}
struct MyType2 : IFoo
{
    override int getVal() { return 1; }
}

// Basic
float4 computeDiffuse<L : ILight>(float4 albedo, float3 P, float3 N, L light) { ... }

// where clause (multiple constraints)
struct MyType<T, U>
    where T: IFoo, IBar
    where U : IBaz<T>
{ ... }

// Simplified constraint syntax
int myMethod<T:IFoo>(T arg) { ... }

// Generic value parameters
void g<let n : int>() { ... }

// Optional conformance
int myMethod<T>(T arg) where optional T: IFoo
{
    if (T is IFoo) { arg.myMethod(1.0); }
}

interface IMaterial
{
    associatedtype B : IBRDF;
    B evalPattern(float3 pos, float2 uv);
}

struct MyCoolMaterial : IMaterial
{
    typedef DisneyBRDF B;
    B evalPattern(float3 pos, float2 uv) { ... }
}

type_param M : IMaterial;
M gMaterial;

[Differentiable]
float2 foo(float a, float b) { return float2(a * b * b, a * a); }

DifferentialPair<float> dp_a = diffPair(1.0, 1.0); // (value, derivative)
DifferentialPair<float> dp_b = diffPair(2.4, 0.0);
DifferentialPair<float2> out = fwd_diff(foo)(dp_a, dp_b);
float2 primal     = out.p;
float2 derivative = out.d;

DifferentialPair<float> dp_a = diffPair(1.0);
DifferentialPair<float> dp_b = diffPair(2.4);
float2 dL_doutput = float2(1.0, 0.0);
bwd_diff(foo)(dp_a, dp_b, dL_doutput);
float dL_da = dp_a.d;
float dL_db = dp_b.d;

struct MyType : IDifferentiable { float x; float y; }

[Differentiable]
[ForwardDerivative(myForwardDeriv)]
[BackwardDerivative(myBackwardDeriv)]
float myFunc(float x) { ... }

// scene.slang
module scene;
__include "scene-helpers";   // NOT preprocessor — no macro sharing

// scene-helpers.slang
implementing scene;
// all entities in module are mutually visible regardless of include order

__include dir.sub_file;           // → "dir/sub-file.slang"
__include "dir/sub-file.slang";

[require(spvShaderClockKHR)]
[require(glsl, GL_EXT_shader_realtime_clock)]
[require(hlsl_nvapi)]
uint2 getClock() { ... }
// Combined: (spvShaderClockKHR | glsl + GL_EXT_shader_realtime_clock | hlsl_nvapi)

void myFunc()
{
    __target_switch
    {
    case spirv: /* SPIR-V path */ break;
    case hlsl:  /* HLSL path  */ break;
    }
}

// Use a named alias instead of spelling out the full disjunction:
[require(sm_6_6)]
void myFunc() { ... }

// 1. Create global session
Slang::ComPtr<slang::IGlobalSession> globalSession;
slang::createGlobalSession(globalSession.writeRef());

// 2. Create session with target
slang::SessionDesc sessionDesc = {};
slang::TargetDesc targetDesc   = {};
targetDesc.format   = SLANG_SPIRV;
targetDesc.profile  = SLANG_PROFILE_GLSL_450;
sessionDesc.targets      = &targetDesc;
sessionDesc.targetCount  = 1;
Slang::ComPtr<slang::ISession> session;
globalSession->createSession(sessionDesc, session.writeRef());

// 3. Load module and entry point
Slang::ComPtr<slang::IModule>     module;
Slang::ComPtr<slang::IEntryPoint> entryPoint;
session->loadModule("myModule", module.writeRef());
module->findEntryPointByName("main", entryPoint.writeRef());

// 4. Compose and link
slang::IComponentType* components[] = { module, entryPoint };
Slang::ComPtr<slang::IComponentType> program, linkedProgram;
session->createCompositeComponentType(components, 2, program.writeRef());
program->link(linkedProgram.writeRef());

// 5. Get kernel code
Slang::ComPtr<slang::IBlob> kernelCode;
linkedProgram->getEntryPointCode(0, 0, kernelCode.writeRef());

find_package(slang REQUIRED PATHS ${CMAKE_INSTALL_PREFIX} NO_DEFAULT_PATH)
target_link_libraries(yourLib PUBLIC slang::slang)

slang::ProgramLayout* layout = program->getLayout(targetIndex);

// Enumerate global parameters
int paramCount = layout->getParameterCount();
for (int i = 0; i < paramCount; i++)
{
    slang::VariableLayoutReflection* param = layout->getParameterByIndex(i);
    const char* name = param->getName();
    int binding      = param->getBindingIndex();
    int space        = param->getBindingSpace();
}

// Entry point layouts (stage, varying params)
slang::EntryPointLayout* ep = layout->getEntryPointByIndex(0);
slang::Stage stage = ep->getStage();

[[vk::binding(0, 1)]] Texture2D myTexture;
[[vk::push_constant]]  cbuffer PC { float4 color; };
[[vk::shader_record]]  cbuffer SR { uint id; };

# Basic
slangc shader.slang -target spirv -o shader.spv
slangc shader.slang -target dxil  -o shader.dxil
slangc shader.slang -target glsl  -o shader.glsl
slangc shader.slang -target cuda  -o shader.cu
slangc shader.slang -target metal -o shader.metal
slangc shader.slang -target cpp   -o shader.cpp

# Multi-target
slangc shader.slang -target spirv -o shader.spv -target dxil -o shader.dxil

# Entry point and stage
slangc shader.slang -target spirv -entry mainCS -stage compute -o out.spv

# Profile
slangc shader.slang -target glsl  -profile glsl_460 -o out.glsl
slangc shader.slang -target dxil  -profile sm_6_7   -o out.dxil

# Matrix layout (important for row-major engines like xMath)
slangc shader.slang -target spirv -matrix-layout-row-major -o out.spv

# Optimization
slangc shader.slang -O0   # no optimization
slangc shader.slang -O2   # standard
slangc shader.slang -O3   # aggressive

# Debug info
slangc shader.slang -g -o out.spv

# Include paths and macros
slangc shader.slang -I./include -DENABLE_SHADOWS=1 -o out.spv

# Capabilities
slangc shader.slang -capability spvShaderClockKHR -target spirv -o out.spv

# Vulkan-specific
slangc shader.slang -target spirv -fvk-use-entrypoint-name -o out.spv
slangc shader.slang -target spirv -fvk-use-gl-layout       -o out.spv

# Precompiled modules
slangc shader.slang -r prebuilt.slang-module -target spirv -o out.spv

# Emit IR
slangc shader.slang -emit-ir -o shader.slang-module