ShaderInjectionSystem.cpp

#include "ShaderInjectionSystem.h"

void SetupShaderInjection(ID3D11Device* device) {
    ShaderInjectionSystem injector(device);

    // Register custom injector
    injector.RegisterInjector("LIGHTING", [](const std::string& code) {
        return "#define ENABLE_PBR 1\n"
               "#define MAX_LIGHTS 8\n" +
               code;
    });

    // Add injection points
    injector.AddInjectionPoint("PixelShader.hlsl", {
        "// @INJECTION_POINT: LIGHTING",
        R"(
            float3 CalculatePBR(float3 albedo, float metallic, float roughness) {
                // PBR calculation code
                return albedo;
            }
        )",
        true
    });

    // Create shader variant
    ShaderVariant highQualityVariant;
    highQualityVariant.name = "HighQuality";
    highQualityVariant.defines = {
        "MAX_LIGHTS=16",
        "ENABLE_SHADOWS=1",
        "ENABLE_AO=1"
    };
    highQualityVariant.injectionPoints = {
        {
            "// @INJECTION_POINT: SHADOW",
            R"(
                float CalculateShadow(float4 position) {
                    // High quality shadow calculation
                    return 1.0f;
                }
            )",
            true
        }
    };

    injector.CreateVariant("PixelShader.hlsl", highQualityVariant);

    // Compile shader with variant
    auto shader = injector.CompileVertexShader(
        "VertexShader.hlsl", 
        "HighQuality"
    );

    // Runtime patching
    injector.PatchShader(
        "PixelShader.hlsl",
        "// @INJECTION_POINT: LIGHTING",
        R"(
            float3 CalculateLighting(float3 normal, float3 position) {
                // New lighting calculation
                return float3(1, 1, 1);
            }
        )"
    );
}

// Example shader code (PixelShader.hlsl):
/*
cbuffer Constants : register(b0) {
    float4x4 WorldViewProj;
}

// @INJECTION_POINT: LIGHTING

float4 main(VSOutput input) : SV_Target {
    float4 color = input.Color;
    
    // @INJECTION_POINT: SHADOW
    
    return color;
}
*/