XCEngine/tests/Rendering/unit/test_builtin_forward_pipeline.cpp

#include <gtest/gtest.h>

#include "Rendering/Detail/ShaderVariantUtils.h"

#include <XCEngine/Rendering/Builtin/BuiltinPassLayoutUtils.h>
#include <XCEngine/Rendering/Passes/BuiltinDepthOnlyPass.h>
#include <XCEngine/Rendering/Passes/BuiltinObjectIdPass.h>
#include <XCEngine/Rendering/Passes/BuiltinShadowCasterPass.h>
#include <XCEngine/Rendering/Pipelines/BuiltinForwardPipeline.h>
#include <XCEngine/Resources/BuiltinResources.h>
#include <XCEngine/Resources/Mesh/Mesh.h>
#include <XCEngine/Resources/Shader/Shader.h>
#include <XCEngine/Resources/Shader/ShaderLoader.h>
#include <XCEngine/RHI/RHIEnums.h>
#include <XCEngine/RHI/ShaderCompiler/SpirvShaderCompiler.h>

#include <fstream>
#include <iostream>

using namespace XCEngine::Rendering::Pipelines;
using namespace XCEngine::Rendering::Passes;
using namespace XCEngine::Rendering;
using namespace XCEngine::Containers;
using namespace XCEngine::Resources;
using namespace XCEngine::RHI;

TEST(BuiltinForwardPipeline_Test, UsesFloat3PositionInputLayoutForStaticMeshVertices) {
    const InputLayoutDesc inputLayout = BuiltinForwardPipeline::BuildInputLayout();

    ASSERT_EQ(inputLayout.elements.size(), 3u);

    const InputElementDesc& position = inputLayout.elements[0];
    EXPECT_EQ(position.semanticName, "POSITION");
    EXPECT_EQ(position.semanticIndex, 0u);
    EXPECT_EQ(position.format, static_cast<uint32_t>(Format::R32G32B32_Float));
    EXPECT_EQ(position.inputSlot, 0u);
    EXPECT_EQ(position.alignedByteOffset, 0u);

    const InputElementDesc& normal = inputLayout.elements[1];
    EXPECT_EQ(normal.semanticName, "NORMAL");
    EXPECT_EQ(normal.semanticIndex, 0u);
    EXPECT_EQ(normal.format, static_cast<uint32_t>(Format::R32G32B32_Float));
    EXPECT_EQ(normal.inputSlot, 0u);
    EXPECT_EQ(normal.alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, normal)));

    const InputElementDesc& texcoord = inputLayout.elements[2];
    EXPECT_EQ(texcoord.semanticName, "TEXCOORD");
    EXPECT_EQ(texcoord.semanticIndex, 0u);
    EXPECT_EQ(texcoord.format, static_cast<uint32_t>(Format::R32G32_Float));
    EXPECT_EQ(texcoord.inputSlot, 0u);
    EXPECT_EQ(texcoord.alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, uv0)));
}

TEST(BuiltinForwardPipeline_Test, SplitsSceneItemsIntoOpaqueAndTransparentQueueRanges) {
    EXPECT_FALSE(IsTransparentRenderQueue(static_cast<int>(MaterialRenderQueue::Background)));
    EXPECT_FALSE(IsTransparentRenderQueue(static_cast<int>(MaterialRenderQueue::Geometry)));
    EXPECT_FALSE(IsTransparentRenderQueue(static_cast<int>(MaterialRenderQueue::AlphaTest)));
    EXPECT_TRUE(IsTransparentRenderQueue(static_cast<int>(MaterialRenderQueue::Transparent)));
    EXPECT_TRUE(IsTransparentRenderQueue(static_cast<int>(MaterialRenderQueue::Overlay)));
}

TEST(BuiltinForwardPipeline_Test, BuiltinForwardShaderUsesUnityStyleSingleSourceSurfaceContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinForwardLitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPropertyDesc* cutoff = shader->FindProperty("_Cutoff");
    ASSERT_NE(cutoff, nullptr);
    EXPECT_EQ(cutoff->type, ShaderPropertyType::Range);
    EXPECT_EQ(cutoff->semantic, "AlphaCutoff");

    const ShaderPass* pass = shader->FindPass("ForwardLit");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());
    EXPECT_TRUE(pass->hasFixedFunctionState);
    EXPECT_EQ(pass->fixedFunctionState.cullMode, MaterialCullMode::Back);
    EXPECT_TRUE(pass->fixedFunctionState.depthWriteEnable);
    EXPECT_EQ(pass->fixedFunctionState.depthFunc, MaterialComparisonFunc::LessEqual);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuiltinUnlitShaderUsesUnityStyleSingleSourceSurfaceContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinUnlitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("Unlit");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());
    EXPECT_TRUE(pass->hasFixedFunctionState);
    EXPECT_EQ(pass->fixedFunctionState.cullMode, MaterialCullMode::Back);
    EXPECT_TRUE(pass->fixedFunctionState.depthWriteEnable);
    EXPECT_EQ(pass->fixedFunctionState.depthFunc, MaterialComparisonFunc::LessEqual);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuiltinUnlitShaderBuildsVulkanRuntimeSourceWithResolvedBindings) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinUnlitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("Unlit");
    ASSERT_NE(pass, nullptr);

    const ShaderStageVariant* fragmentVariant =
        shader->FindVariant(
            "Unlit",
            XCEngine::Resources::ShaderType::Fragment,
            XCEngine::Resources::ShaderBackend::Vulkan);
    ASSERT_NE(fragmentVariant, nullptr);

    const std::string runtimeSource =
        ::XCEngine::Rendering::Detail::BuildRuntimeShaderSource(
            *pass,
            XCEngine::Resources::ShaderBackend::Vulkan,
            *fragmentVariant);

    EXPECT_NE(
        runtimeSource.find("cbuffer MaterialConstants : register(b0, space1)"),
        std::string::npos);
    EXPECT_NE(runtimeSource.find("BaseColorTexture"), std::string::npos);
    EXPECT_NE(runtimeSource.find("space2"), std::string::npos);
    EXPECT_NE(runtimeSource.find("LinearClampSampler"), std::string::npos);
    EXPECT_NE(runtimeSource.find("space3"), std::string::npos);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, VulkanRuntimeCompileDescRewritesUnityStyleUnlitBindingsToDescriptorSpaces) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinUnlitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("Unlit");
    ASSERT_NE(pass, nullptr);

    const ShaderStageVariant* d3d12Fragment = shader->FindVariant(
        "Unlit",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::D3D12);
    ASSERT_NE(d3d12Fragment, nullptr);

    ShaderCompileDesc d3d12CompileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::D3D12,
        *d3d12Fragment,
        d3d12CompileDesc);
    const std::string d3d12Source(
        reinterpret_cast<const char*>(d3d12CompileDesc.source.data()),
        d3d12CompileDesc.source.size());
    EXPECT_NE(d3d12Source.find("BaseColorTexture"), std::string::npos);
    EXPECT_NE(d3d12Source.find("LinearClampSampler"), std::string::npos);
    EXPECT_EQ(d3d12Source.find("space2"), std::string::npos);
    EXPECT_EQ(d3d12Source.find("space3"), std::string::npos);

    const ShaderStageVariant* vulkanFragment = shader->FindVariant(
        "Unlit",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::Vulkan);
    ASSERT_NE(vulkanFragment, nullptr);

    ShaderCompileDesc vulkanCompileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::Vulkan,
        *vulkanFragment,
        vulkanCompileDesc);
    const std::string vulkanSource(
        reinterpret_cast<const char*>(vulkanCompileDesc.source.data()),
        vulkanCompileDesc.source.size());
    EXPECT_NE(vulkanSource.find("cbuffer MaterialConstants : register(b0, space1)"), std::string::npos);
    EXPECT_NE(vulkanSource.find("BaseColorTexture"), std::string::npos);
    EXPECT_NE(vulkanSource.find("space2"), std::string::npos);
    EXPECT_NE(vulkanSource.find("LinearClampSampler"), std::string::npos);
    EXPECT_NE(vulkanSource.find("space3"), std::string::npos);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, VulkanRuntimeCompileDescRewritesUnityStyleForwardBindingsToDescriptorSpaces) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinForwardLitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ForwardLit");
    ASSERT_NE(pass, nullptr);

    ShaderKeywordSet shadowKeywords = {};
    shadowKeywords.enabledKeywords.PushBack("XC_MAIN_LIGHT_SHADOWS");

    const ShaderStageVariant* d3d12Fragment = shader->FindVariant(
        "ForwardLit",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::D3D12,
        shadowKeywords);
    ASSERT_NE(d3d12Fragment, nullptr);

    ShaderCompileDesc d3d12CompileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::D3D12,
        *d3d12Fragment,
        d3d12CompileDesc);
    const std::string d3d12Source(
        reinterpret_cast<const char*>(d3d12CompileDesc.source.data()),
        d3d12CompileDesc.source.size());
    EXPECT_NE(d3d12Source.find("cbuffer LightingConstants : register(b1)"), std::string::npos);
    EXPECT_NE(d3d12Source.find("Texture2D ShadowMapTexture : register(t1)"), std::string::npos);
    EXPECT_EQ(d3d12Source.find("space1"), std::string::npos);
    EXPECT_EQ(d3d12Source.find("space6"), std::string::npos);

    const ShaderStageVariant* vulkanFragment = shader->FindVariant(
        "ForwardLit",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::Vulkan,
        shadowKeywords);
    ASSERT_NE(vulkanFragment, nullptr);

    ShaderCompileDesc vulkanCompileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::Vulkan,
        *vulkanFragment,
        vulkanCompileDesc);
    const std::string vulkanSource(
        reinterpret_cast<const char*>(vulkanCompileDesc.source.data()),
        vulkanCompileDesc.source.size());
    EXPECT_NE(vulkanSource.find("cbuffer PerObjectConstants : register(b0, space0)"), std::string::npos);
    EXPECT_NE(vulkanSource.find("cbuffer LightingConstants : register(b0, space1)"), std::string::npos);
    EXPECT_NE(vulkanSource.find("cbuffer MaterialConstants : register(b0, space2)"), std::string::npos);
    EXPECT_NE(vulkanSource.find("cbuffer ShadowReceiverConstants : register(b0, space3)"), std::string::npos);
    EXPECT_NE(vulkanSource.find("Texture2D BaseColorTexture : register(t0, space4)"), std::string::npos);
    EXPECT_NE(vulkanSource.find("SamplerState LinearClampSampler : register(s0, space5)"), std::string::npos);
    EXPECT_NE(vulkanSource.find("Texture2D ShadowMapTexture : register(t0, space6)"), std::string::npos);
    EXPECT_NE(vulkanSource.find("SamplerState ShadowMapSampler : register(s0, space7)"), std::string::npos);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, OpenGLRuntimeTranspilesForwardShadowVariantToLegacyClipConventions) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinForwardLitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ForwardLit");
    ASSERT_NE(pass, nullptr);

    ShaderKeywordSet shadowKeywords = {};
    shadowKeywords.enabledKeywords.PushBack("XC_MAIN_LIGHT_SHADOWS");

    const ShaderStageVariant* openGLFragment = shader->FindVariant(
        "ForwardLit",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::OpenGL,
        shadowKeywords);
    ASSERT_NE(openGLFragment, nullptr);

    ShaderCompileDesc compileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::OpenGL,
        *openGLFragment,
        compileDesc);
    const std::string runtimeSource(
        reinterpret_cast<const char*>(compileDesc.source.data()),
        compileDesc.source.size());
    EXPECT_NE(runtimeSource.find("const float shadowUvY = shadowNdc.y * 0.5f + 0.5f;"), std::string::npos);
    EXPECT_NE(
        runtimeSource.find("shadowNdc.z < -1.0f || shadowNdc.z > 1.0f"),
        std::string::npos);
    EXPECT_NE(
        runtimeSource.find(
            "const float receiverDepth = shadowNdc.z * 0.5f + 0.5f - gShadowBiasAndTexelSize.x;"),
        std::string::npos);

    XCEngine::RHI::CompiledSpirvShader spirvShader = {};
    std::string errorMessage;
    ASSERT_TRUE(
        XCEngine::RHI::CompileSpirvShader(
            compileDesc,
            XCEngine::RHI::SpirvTargetEnvironment::Vulkan,
            spirvShader,
            &errorMessage))
        << errorMessage;

    std::string glslSource;
    ASSERT_TRUE(XCEngine::RHI::TranspileSpirvToOpenGLGLSL(spirvShader, glslSource, &errorMessage))
        << errorMessage;
    EXPECT_NE(
        glslSource.find("uniform sampler2D SPIRV_Cross_CombinedBaseColorTextureLinearClampSampler;"),
        std::string::npos);
    EXPECT_NE(
        glslSource.find("uniform sampler2D SPIRV_Cross_CombinedShadowMapTextureShadowMapSampler;"),
        std::string::npos);
    EXPECT_NE(
        glslSource.find("spvWorkaroundRowMajor(ShadowReceiverConstants.gWorldToShadowMatrix)"),
        std::string::npos);
    EXPECT_NE(glslSource.find("texture(SPIRV_Cross_CombinedShadowMapTextureShadowMapSampler"), std::string::npos);

    delete shader;
}

TEST(BuiltinDepthStylePass_Test, OpenGLRuntimeTranspilesDepthOnlyAlphaVariantWithTexcoordAtLocation2) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinDepthOnlyShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("DepthOnly");
    ASSERT_NE(pass, nullptr);

    ShaderKeywordSet alphaKeywords = {};
    alphaKeywords.enabledKeywords.PushBack("XC_ALPHA_TEST");

    const ShaderStageVariant* openGLVertex = shader->FindVariant(
        "DepthOnly",
        XCEngine::Resources::ShaderType::Vertex,
        ShaderBackend::OpenGL,
        alphaKeywords);
    ASSERT_NE(openGLVertex, nullptr);

    const ShaderStageVariant* openGLFragment = shader->FindVariant(
        "DepthOnly",
        XCEngine::Resources::ShaderType::Fragment,
        ShaderBackend::OpenGL,
        alphaKeywords);
    ASSERT_NE(openGLFragment, nullptr);

    auto transpileStage = [](const ShaderPass& targetPass,
                             const ShaderStageVariant& variant,
                             std::string& glslSource) {
        ShaderCompileDesc compileDesc = {};
        ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
            targetPass,
            XCEngine::Resources::ShaderBackend::OpenGL,
            variant,
            compileDesc);

        XCEngine::RHI::CompiledSpirvShader spirvShader = {};
        std::string errorMessage;
        EXPECT_TRUE(
            XCEngine::RHI::CompileSpirvShader(
                compileDesc,
                XCEngine::RHI::SpirvTargetEnvironment::Vulkan,
                spirvShader,
                &errorMessage))
            << errorMessage;
        EXPECT_TRUE(XCEngine::RHI::TranspileSpirvToOpenGLGLSL(spirvShader, glslSource, &errorMessage))
            << errorMessage;
    };

    std::string vertexGlsl;
    transpileStage(*pass, *openGLVertex, vertexGlsl);
    EXPECT_NE(vertexGlsl.find("layout(location = 2) in vec2"), std::string::npos);

    std::string fragmentGlsl;
    transpileStage(*pass, *openGLFragment, fragmentGlsl);
    EXPECT_NE(fragmentGlsl.find("discard;"), std::string::npos);
    EXPECT_NE(fragmentGlsl.find("gl_FragDepth"), std::string::npos);

    delete shader;
}

TEST(BuiltinDepthStylePass_Test, OpenGLRuntimeTranspilesShadowCasterAlphaVariantWithTexcoordAtLocation2) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinShadowCasterShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ShadowCaster");
    ASSERT_NE(pass, nullptr);

    ShaderKeywordSet alphaKeywords = {};
    alphaKeywords.enabledKeywords.PushBack("XC_ALPHA_TEST");

    const ShaderStageVariant* openGLVertex = shader->FindVariant(
        "ShadowCaster",
        XCEngine::Resources::ShaderType::Vertex,
        ShaderBackend::OpenGL,
        alphaKeywords);
    ASSERT_NE(openGLVertex, nullptr);

    const ShaderStageVariant* openGLFragment = shader->FindVariant(
        "ShadowCaster",
        XCEngine::Resources::ShaderType::Fragment,
        ShaderBackend::OpenGL,
        alphaKeywords);
    ASSERT_NE(openGLFragment, nullptr);

    auto transpileStage = [](const ShaderPass& targetPass,
                             const ShaderStageVariant& variant,
                             std::string& glslSource) {
        ShaderCompileDesc compileDesc = {};
        ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
            targetPass,
            XCEngine::Resources::ShaderBackend::OpenGL,
            variant,
            compileDesc);

        XCEngine::RHI::CompiledSpirvShader spirvShader = {};
        std::string errorMessage;
        EXPECT_TRUE(
            XCEngine::RHI::CompileSpirvShader(
                compileDesc,
                XCEngine::RHI::SpirvTargetEnvironment::Vulkan,
                spirvShader,
                &errorMessage))
            << errorMessage;
        EXPECT_TRUE(XCEngine::RHI::TranspileSpirvToOpenGLGLSL(spirvShader, glslSource, &errorMessage))
            << errorMessage;
    };

    std::string vertexGlsl;
    transpileStage(*pass, *openGLVertex, vertexGlsl);
    EXPECT_NE(vertexGlsl.find("layout(location = 2) in vec2"), std::string::npos);

    std::string fragmentGlsl;
    transpileStage(*pass, *openGLFragment, fragmentGlsl);
    EXPECT_NE(fragmentGlsl.find("discard;"), std::string::npos);
    EXPECT_NE(fragmentGlsl.find("gl_FragDepth"), std::string::npos);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuiltinSkyboxShaderUsesUnityStyleSingleSourceContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinSkyboxShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("Skybox");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());
    EXPECT_TRUE(pass->hasFixedFunctionState);
    EXPECT_EQ(pass->fixedFunctionState.cullMode, MaterialCullMode::None);
    EXPECT_FALSE(pass->fixedFunctionState.depthWriteEnable);
    EXPECT_EQ(pass->fixedFunctionState.depthFunc, MaterialComparisonFunc::LessEqual);

    const ShaderPropertyDesc* tint = shader->FindProperty("_Tint");
    ASSERT_NE(tint, nullptr);
    EXPECT_EQ(tint->type, ShaderPropertyType::Color);
    EXPECT_EQ(tint->semantic, "Tint");

    const ShaderPropertyDesc* exposure = shader->FindProperty("_Exposure");
    ASSERT_NE(exposure, nullptr);
    EXPECT_EQ(exposure->type, ShaderPropertyType::Float);
    EXPECT_EQ(exposure->semantic, "Exposure");

    const ShaderPropertyDesc* rotation = shader->FindProperty("_Rotation");
    ASSERT_NE(rotation, nullptr);
    EXPECT_EQ(rotation->type, ShaderPropertyType::Float);
    EXPECT_EQ(rotation->semantic, "Rotation");

    const ShaderPropertyDesc* panoramic = shader->FindProperty("_MainTex");
    ASSERT_NE(panoramic, nullptr);
    EXPECT_EQ(panoramic->type, ShaderPropertyType::Texture2D);
    EXPECT_EQ(panoramic->semantic, "SkyboxPanoramicTexture");

    const ShaderPropertyDesc* cubemap = shader->FindProperty("_Tex");
    ASSERT_NE(cubemap, nullptr);
    EXPECT_EQ(cubemap->type, ShaderPropertyType::TextureCube);
    EXPECT_EQ(cubemap->semantic, "SkyboxTexture");

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuildsBuiltinPassResourceBindingPlanFromImplicitSkyboxShaderContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinSkyboxShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("Skybox");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    ASSERT_EQ(plan.bindings.Size(), 5u);
    EXPECT_TRUE(plan.environment.IsValid());
    EXPECT_TRUE(plan.material.IsValid());
    EXPECT_TRUE(plan.skyboxPanoramicTexture.IsValid());
    EXPECT_TRUE(plan.skyboxTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 5u);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuiltinFinalColorShaderUsesUnityStyleSingleSourceContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinFinalColorShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("FinalColor");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());
    EXPECT_TRUE(pass->hasFixedFunctionState);
    EXPECT_EQ(pass->fixedFunctionState.cullMode, MaterialCullMode::None);
    EXPECT_FALSE(pass->fixedFunctionState.depthWriteEnable);
    EXPECT_EQ(pass->fixedFunctionState.depthFunc, MaterialComparisonFunc::Always);

    const ShaderPropertyDesc* colorScale = shader->FindProperty("_ColorScale");
    ASSERT_NE(colorScale, nullptr);
    EXPECT_EQ(colorScale->type, ShaderPropertyType::Color);

    const ShaderPropertyDesc* exposure = shader->FindProperty("_Exposure");
    ASSERT_NE(exposure, nullptr);
    EXPECT_EQ(exposure->type, ShaderPropertyType::Float);

    const ShaderPropertyDesc* outputTransferMode = shader->FindProperty("_OutputTransferMode");
    ASSERT_NE(outputTransferMode, nullptr);
    EXPECT_EQ(outputTransferMode->type, ShaderPropertyType::Float);

    const ShaderPropertyDesc* toneMappingMode = shader->FindProperty("_ToneMappingMode");
    ASSERT_NE(toneMappingMode, nullptr);
    EXPECT_EQ(toneMappingMode->type, ShaderPropertyType::Float);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuildsBuiltinPassResourceBindingPlanFromImplicitFinalColorShaderContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinFinalColorShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("FinalColor");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    ASSERT_EQ(plan.bindings.Size(), 3u);
    EXPECT_TRUE(plan.passConstants.IsValid());
    EXPECT_TRUE(plan.sourceColorTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 3u);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuiltinColorScalePostProcessShaderUsesUnityStyleSingleSourceContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinColorScalePostProcessShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ColorScale");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());
    EXPECT_TRUE(pass->hasFixedFunctionState);
    EXPECT_EQ(pass->fixedFunctionState.cullMode, MaterialCullMode::None);
    EXPECT_FALSE(pass->fixedFunctionState.depthWriteEnable);
    EXPECT_EQ(pass->fixedFunctionState.depthFunc, MaterialComparisonFunc::Always);

    const ShaderPropertyDesc* colorScale = shader->FindProperty("_ColorScale");
    ASSERT_NE(colorScale, nullptr);
    EXPECT_EQ(colorScale->type, ShaderPropertyType::Color);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuildsBuiltinPassResourceBindingPlanFromImplicitColorScalePostProcessShaderContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinColorScalePostProcessShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ColorScale");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    ASSERT_EQ(plan.bindings.Size(), 3u);
    EXPECT_TRUE(plan.passConstants.IsValid());
    EXPECT_TRUE(plan.sourceColorTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 3u);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, VulkanRuntimeCompileDescRewritesUnityStyleFinalColorBindingsToDescriptorSpaces) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinFinalColorShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("FinalColor");
    ASSERT_NE(pass, nullptr);

    const ShaderStageVariant* d3d12Fragment = shader->FindVariant(
        "FinalColor",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::D3D12);
    ASSERT_NE(d3d12Fragment, nullptr);

    ShaderCompileDesc d3d12CompileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::D3D12,
        *d3d12Fragment,
        d3d12CompileDesc);
    const std::string d3d12Source(
        reinterpret_cast<const char*>(d3d12CompileDesc.source.data()),
        d3d12CompileDesc.source.size());
    EXPECT_NE(d3d12Source.find("cbuffer FinalColorConstants : register(b0)"), std::string::npos);
    EXPECT_NE(d3d12Source.find("Texture2D gSourceColorTexture : register(t0)"), std::string::npos);
    EXPECT_NE(d3d12Source.find("SamplerState gLinearClampSampler : register(s0)"), std::string::npos);
    EXPECT_EQ(d3d12Source.find("space1"), std::string::npos);
    EXPECT_EQ(d3d12Source.find("space2"), std::string::npos);

    const ShaderStageVariant* vulkanFragment = shader->FindVariant(
        "FinalColor",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::Vulkan);
    ASSERT_NE(vulkanFragment, nullptr);

    const std::string runtimeSource =
        ::XCEngine::Rendering::Detail::BuildRuntimeShaderSource(
            *pass,
            XCEngine::Resources::ShaderBackend::Vulkan,
            *vulkanFragment);
    EXPECT_NE(
        runtimeSource.find("cbuffer FinalColorConstants : register(b0, space0)"),
        std::string::npos);
    EXPECT_NE(
        runtimeSource.find("Texture2D gSourceColorTexture : register(t0, space1)"),
        std::string::npos);
    EXPECT_NE(
        runtimeSource.find("SamplerState gLinearClampSampler : register(s0, space2)"),
        std::string::npos);

    ShaderCompileDesc vulkanCompileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::Vulkan,
        *vulkanFragment,
        vulkanCompileDesc);
    const std::string vulkanSource(
        reinterpret_cast<const char*>(vulkanCompileDesc.source.data()),
        vulkanCompileDesc.source.size());
    EXPECT_NE(vulkanSource.find("ApplyLinearToSRGB"), std::string::npos);
    EXPECT_NE(vulkanSource.find("ApplyToneMapping"), std::string::npos);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, OpenGLRuntimeTranspilesFinalColorVariantToCombinedSourceSampler) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinFinalColorShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("FinalColor");
    ASSERT_NE(pass, nullptr);

    const ShaderStageVariant* openGLFragment = shader->FindVariant(
        "FinalColor",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::OpenGL);
    ASSERT_NE(openGLFragment, nullptr);

    ShaderCompileDesc compileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::OpenGL,
        *openGLFragment,
        compileDesc);

    XCEngine::RHI::CompiledSpirvShader spirvShader = {};
    std::string errorMessage;
    ASSERT_TRUE(
        XCEngine::RHI::CompileSpirvShader(
            compileDesc,
            XCEngine::RHI::SpirvTargetEnvironment::Vulkan,
            spirvShader,
            &errorMessage))
        << errorMessage;

    std::string glslSource;
    ASSERT_TRUE(XCEngine::RHI::TranspileSpirvToOpenGLGLSL(spirvShader, glslSource, &errorMessage))
        << errorMessage;
    EXPECT_NE(glslSource.find("uniform sampler2D SPIRV_Cross_Combined"), std::string::npos);
    EXPECT_NE(glslSource.find("texture(SPIRV_Cross_Combined"), std::string::npos);
    EXPECT_NE(glslSource.find("FinalColorConstants"), std::string::npos);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, VulkanRuntimeCompileDescRewritesUnityStyleColorScaleBindingsToDescriptorSpaces) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinColorScalePostProcessShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ColorScale");
    ASSERT_NE(pass, nullptr);

    const ShaderStageVariant* d3d12Fragment = shader->FindVariant(
        "ColorScale",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::D3D12);
    ASSERT_NE(d3d12Fragment, nullptr);

    ShaderCompileDesc d3d12CompileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::D3D12,
        *d3d12Fragment,
        d3d12CompileDesc);
    const std::string d3d12Source(
        reinterpret_cast<const char*>(d3d12CompileDesc.source.data()),
        d3d12CompileDesc.source.size());
    EXPECT_NE(d3d12Source.find("cbuffer PostProcessConstants : register(b0)"), std::string::npos);
    EXPECT_NE(d3d12Source.find("Texture2D gSourceColorTexture : register(t0)"), std::string::npos);
    EXPECT_NE(d3d12Source.find("SamplerState gLinearClampSampler : register(s0)"), std::string::npos);
    EXPECT_EQ(d3d12Source.find("space1"), std::string::npos);
    EXPECT_EQ(d3d12Source.find("space2"), std::string::npos);

    const ShaderStageVariant* vulkanFragment = shader->FindVariant(
        "ColorScale",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::Vulkan);
    ASSERT_NE(vulkanFragment, nullptr);

    const std::string runtimeSource =
        ::XCEngine::Rendering::Detail::BuildRuntimeShaderSource(
            *pass,
            XCEngine::Resources::ShaderBackend::Vulkan,
            *vulkanFragment);
    EXPECT_NE(
        runtimeSource.find("cbuffer PostProcessConstants : register(b0, space0)"),
        std::string::npos);
    EXPECT_NE(
        runtimeSource.find("Texture2D gSourceColorTexture : register(t0, space1)"),
        std::string::npos);
    EXPECT_NE(
        runtimeSource.find("SamplerState gLinearClampSampler : register(s0, space2)"),
        std::string::npos);

    ShaderCompileDesc vulkanCompileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::Vulkan,
        *vulkanFragment,
        vulkanCompileDesc);
    const std::string vulkanSource(
        reinterpret_cast<const char*>(vulkanCompileDesc.source.data()),
        vulkanCompileDesc.source.size());
    EXPECT_NE(vulkanSource.find("gSourceColorTexture.Sample"), std::string::npos);
    EXPECT_NE(vulkanSource.find("gColorScale"), std::string::npos);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, OpenGLRuntimeTranspilesColorScaleVariantToCombinedSourceSampler) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinColorScalePostProcessShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ColorScale");
    ASSERT_NE(pass, nullptr);

    const ShaderStageVariant* openGLFragment = shader->FindVariant(
        "ColorScale",
        XCEngine::Resources::ShaderType::Fragment,
        XCEngine::Resources::ShaderBackend::OpenGL);
    ASSERT_NE(openGLFragment, nullptr);

    ShaderCompileDesc compileDesc = {};
    ::XCEngine::Rendering::Detail::ApplyShaderStageVariant(
        *pass,
        XCEngine::Resources::ShaderBackend::OpenGL,
        *openGLFragment,
        compileDesc);

    XCEngine::RHI::CompiledSpirvShader spirvShader = {};
    std::string errorMessage;
    ASSERT_TRUE(
        XCEngine::RHI::CompileSpirvShader(
            compileDesc,
            XCEngine::RHI::SpirvTargetEnvironment::Vulkan,
            spirvShader,
            &errorMessage))
        << errorMessage;

    std::string glslSource;
    ASSERT_TRUE(XCEngine::RHI::TranspileSpirvToOpenGLGLSL(spirvShader, glslSource, &errorMessage))
        << errorMessage;
    EXPECT_NE(glslSource.find("uniform sampler2D SPIRV_Cross_Combined"), std::string::npos);
    EXPECT_NE(glslSource.find("texture(SPIRV_Cross_Combined"), std::string::npos);
    EXPECT_NE(glslSource.find("PostProcessConstants"), std::string::npos);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuildsBuiltinPassResourceBindingPlanFromLoadedImplicitForwardShader) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinForwardLitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ForwardLit");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    EXPECT_TRUE(plan.perObject.IsValid());
    EXPECT_TRUE(plan.lighting.IsValid());
    EXPECT_TRUE(plan.material.IsValid());
    EXPECT_TRUE(plan.shadowReceiver.IsValid());
    EXPECT_TRUE(plan.baseColorTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_TRUE(plan.shadowMapTexture.IsValid());
    EXPECT_TRUE(plan.shadowMapSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 8u);
    EXPECT_TRUE(plan.usesConstantBuffers);
    EXPECT_TRUE(plan.usesTextures);
    EXPECT_TRUE(plan.usesSamplers);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, BuildsBuiltinPassResourceBindingPlanFromBuiltinForwardShaderContract) {
    ShaderPass pass = {};
    pass.name = "ForwardLit";

    ShaderPassTagEntry tag = {};
    tag.name = "LightMode";
    tag.value = "ForwardBase";
    pass.tags.PushBack(tag);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(pass, plan, &error)) << error.CStr();
    EXPECT_TRUE(plan.perObject.IsValid());
    EXPECT_TRUE(plan.lighting.IsValid());
    EXPECT_TRUE(plan.material.IsValid());
    EXPECT_TRUE(plan.shadowReceiver.IsValid());
    EXPECT_TRUE(plan.baseColorTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_TRUE(plan.shadowMapTexture.IsValid());
    EXPECT_TRUE(plan.shadowMapSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 8u);
}

TEST(BuiltinForwardPipeline_Test, BuildsBuiltinPassResourceBindingPlanFromImplicitUnlitContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinUnlitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("Unlit");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    EXPECT_TRUE(plan.perObject.IsValid());
    EXPECT_TRUE(plan.material.IsValid());
    EXPECT_TRUE(plan.baseColorTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 4u);
    EXPECT_TRUE(plan.usesConstantBuffers);
    EXPECT_TRUE(plan.usesTextures);
    EXPECT_TRUE(plan.usesSamplers);

    delete shader;
}

TEST(BuiltinForwardPipeline_Test, UsesNormalizedImplicitSetIndicesForForwardSurfaceResources) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinForwardLitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ForwardLit");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    ASSERT_EQ(plan.bindings.Size(), 8u);
    EXPECT_EQ(plan.perObject.set, 0u);
    EXPECT_EQ(plan.lighting.set, 1u);
    EXPECT_EQ(plan.material.set, 2u);
    EXPECT_EQ(plan.shadowReceiver.set, 3u);
    EXPECT_EQ(plan.baseColorTexture.set, 4u);
    EXPECT_EQ(plan.linearClampSampler.set, 5u);
    EXPECT_EQ(plan.shadowMapTexture.set, 6u);
    EXPECT_EQ(plan.shadowMapSampler.set, 7u);

    delete shader;
}

TEST(BuiltinPassLayout_Test, BuildsSharedSetLayoutsFromImplicitForwardResources) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinForwardLitShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ForwardLit");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    ASSERT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();

    std::vector<BuiltinPassSetLayoutMetadata> setLayouts;
    ASSERT_TRUE(TryBuildBuiltinPassSetLayouts(plan, setLayouts, &error)) << error.CStr();
    ASSERT_EQ(setLayouts.size(), 8u);

    EXPECT_EQ(setLayouts[0].layout.bindingCount, 1u);
    EXPECT_FALSE(setLayouts[0].shaderVisible);
    EXPECT_TRUE(setLayouts[0].usesPerObject);
    EXPECT_FALSE(setLayouts[0].usesMaterial);

    EXPECT_EQ(setLayouts[1].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[1].usesLighting);
    EXPECT_FALSE(setLayouts[1].shaderVisible);

    EXPECT_EQ(setLayouts[2].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[2].usesMaterial);
    EXPECT_FALSE(setLayouts[2].shaderVisible);

    EXPECT_EQ(setLayouts[3].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[3].usesShadowReceiver);
    EXPECT_FALSE(setLayouts[3].shaderVisible);

    EXPECT_EQ(setLayouts[4].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[4].usesTexture);
    EXPECT_TRUE(setLayouts[4].shaderVisible);
    EXPECT_EQ(setLayouts[4].heapType, DescriptorHeapType::CBV_SRV_UAV);

    EXPECT_EQ(setLayouts[5].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[5].usesSampler);
    EXPECT_TRUE(setLayouts[5].shaderVisible);
    EXPECT_EQ(setLayouts[5].heapType, DescriptorHeapType::Sampler);

    EXPECT_EQ(setLayouts[6].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[6].usesTexture);
    EXPECT_TRUE(setLayouts[6].shaderVisible);

    EXPECT_EQ(setLayouts[7].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[7].usesSampler);
    EXPECT_TRUE(setLayouts[7].shaderVisible);
    EXPECT_EQ(setLayouts[7].heapType, DescriptorHeapType::Sampler);

    delete shader;
}

TEST(BuiltinDepthStylePass_Test, BuiltinDepthOnlyShaderUsesUnityStyleSingleSourceContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinDepthOnlyShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("DepthOnly");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());
    EXPECT_TRUE(pass->hasFixedFunctionState);
    EXPECT_EQ(pass->fixedFunctionState.cullMode, MaterialCullMode::Back);
    EXPECT_TRUE(pass->fixedFunctionState.depthWriteEnable);
    EXPECT_EQ(pass->fixedFunctionState.depthFunc, MaterialComparisonFunc::LessEqual);

    delete shader;
}

TEST(BuiltinDepthStylePass_Test, BuiltinShadowCasterShaderUsesUnityStyleSingleSourceContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinShadowCasterShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ShadowCaster");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());
    EXPECT_TRUE(pass->hasFixedFunctionState);
    EXPECT_EQ(pass->fixedFunctionState.cullMode, MaterialCullMode::Back);
    EXPECT_TRUE(pass->fixedFunctionState.depthWriteEnable);
    EXPECT_EQ(pass->fixedFunctionState.depthFunc, MaterialComparisonFunc::LessEqual);

    delete shader;
}

TEST(BuiltinObjectIdPass_Test, BuiltinObjectIdShaderUsesUnityStyleSingleSourceContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinObjectIdShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ObjectId");
    ASSERT_NE(pass, nullptr);
    EXPECT_TRUE(pass->resources.Empty());
    EXPECT_TRUE(pass->hasFixedFunctionState);
    EXPECT_EQ(pass->fixedFunctionState.cullMode, MaterialCullMode::Back);
    EXPECT_TRUE(pass->fixedFunctionState.depthWriteEnable);
    EXPECT_EQ(pass->fixedFunctionState.depthFunc, MaterialComparisonFunc::LessEqual);

    delete shader;
}

TEST(BuiltinObjectIdPass_Test, BuildsBuiltinPassResourceBindingPlanFromBuiltinObjectIdShaderContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinObjectIdShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ObjectId");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    ASSERT_EQ(plan.bindings.Size(), 1u);
    EXPECT_TRUE(plan.perObject.IsValid());
    EXPECT_FALSE(plan.material.IsValid());
    EXPECT_FALSE(plan.baseColorTexture.IsValid());
    EXPECT_FALSE(plan.linearClampSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 1u);
    EXPECT_TRUE(plan.usesConstantBuffers);
    EXPECT_FALSE(plan.usesTextures);
    EXPECT_FALSE(plan.usesSamplers);

    delete shader;
}

TEST(BuiltinObjectIdPass_Test, BuildsBuiltinPassResourceBindingPlanFromImplicitObjectIdContract) {
    ShaderPass pass = {};
    pass.name = "ObjectId";

    ShaderPassTagEntry tag = {};
    tag.name = "LightMode";
    tag.value = "ObjectId";
    pass.tags.PushBack(tag);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(pass, plan, &error)) << error.CStr();
    ASSERT_EQ(plan.bindings.Size(), 1u);
    EXPECT_TRUE(plan.perObject.IsValid());
    EXPECT_FALSE(plan.material.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 1u);
}

TEST(BuiltinDepthStylePass_Test, BuildsBuiltinPassResourceBindingPlanFromImplicitDepthOnlyContract) {
    ShaderPass pass = {};
    pass.name = "DepthOnly";

    ShaderPassTagEntry tag = {};
    tag.name = "LightMode";
    tag.value = "DepthOnly";
    pass.tags.PushBack(tag);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    EXPECT_TRUE(TryBuildBuiltinPassResourceBindingPlan(pass, plan, &error)) << error.CStr();
    EXPECT_TRUE(plan.perObject.IsValid());
    EXPECT_TRUE(plan.material.IsValid());
    EXPECT_TRUE(plan.baseColorTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 4u);
}

TEST(BuiltinObjectIdPass_Test, UsesFloat3PositionInputLayoutForStaticMeshVertices) {
    const InputLayoutDesc inputLayout = BuiltinObjectIdPass::BuildInputLayout();

    ASSERT_EQ(inputLayout.elements.size(), 3u);

    const InputElementDesc& position = inputLayout.elements[0];
    EXPECT_EQ(position.semanticName, "POSITION");
    EXPECT_EQ(position.semanticIndex, 0u);
    EXPECT_EQ(position.format, static_cast<uint32_t>(Format::R32G32B32_Float));
    EXPECT_EQ(position.inputSlot, 0u);
    EXPECT_EQ(position.alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, position)));

    const InputElementDesc& normal = inputLayout.elements[1];
    EXPECT_EQ(normal.semanticName, "NORMAL");
    EXPECT_EQ(normal.semanticIndex, 0u);
    EXPECT_EQ(normal.format, static_cast<uint32_t>(Format::R32G32B32_Float));
    EXPECT_EQ(normal.inputSlot, 0u);
    EXPECT_EQ(normal.alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, normal)));

    const InputElementDesc& texcoord = inputLayout.elements[2];
    EXPECT_EQ(texcoord.semanticName, "TEXCOORD");
    EXPECT_EQ(texcoord.semanticIndex, 0u);
    EXPECT_EQ(texcoord.format, static_cast<uint32_t>(Format::R32G32_Float));
    EXPECT_EQ(texcoord.inputSlot, 0u);
    EXPECT_EQ(texcoord.alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, uv0)));
}

TEST(BuiltinPassLayout_Test, BuildsSharedSetLayoutsFromExplicitObjectIdResources) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinObjectIdShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ObjectId");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    ASSERT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();

    std::vector<BuiltinPassSetLayoutMetadata> setLayouts;
    ASSERT_TRUE(TryBuildBuiltinPassSetLayouts(plan, setLayouts, &error)) << error.CStr();
    ASSERT_EQ(setLayouts.size(), 1u);
    EXPECT_EQ(setLayouts[0].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[0].usesPerObject);
    EXPECT_FALSE(setLayouts[0].usesMaterial);
    EXPECT_FALSE(setLayouts[0].usesTexture);
    EXPECT_FALSE(setLayouts[0].usesSampler);
    EXPECT_FALSE(setLayouts[0].shaderVisible);
    EXPECT_EQ(setLayouts[0].heapType, DescriptorHeapType::CBV_SRV_UAV);

    delete shader;
}

TEST(BuiltinPassLayout_Test, BuildsSharedSetLayoutsFromBuiltinDepthOnlyShaderContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinDepthOnlyShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("DepthOnly");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    ASSERT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    EXPECT_TRUE(plan.perObject.IsValid());
    EXPECT_TRUE(plan.material.IsValid());
    EXPECT_TRUE(plan.baseColorTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 4u);
    EXPECT_TRUE(plan.usesConstantBuffers);
    EXPECT_TRUE(plan.usesTextures);
    EXPECT_TRUE(plan.usesSamplers);

    std::vector<BuiltinPassSetLayoutMetadata> setLayouts;
    ASSERT_TRUE(TryBuildBuiltinPassSetLayouts(plan, setLayouts, &error)) << error.CStr();
    ASSERT_EQ(setLayouts.size(), 4u);
    EXPECT_EQ(setLayouts[0].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[0].usesPerObject);
    EXPECT_FALSE(setLayouts[0].usesMaterial);
    EXPECT_FALSE(setLayouts[0].usesTexture);
    EXPECT_FALSE(setLayouts[0].usesSampler);
    EXPECT_EQ(setLayouts[1].layout.bindingCount, 1u);
    EXPECT_FALSE(setLayouts[1].usesPerObject);
    EXPECT_TRUE(setLayouts[1].usesMaterial);
    EXPECT_FALSE(setLayouts[1].usesTexture);
    EXPECT_FALSE(setLayouts[1].usesSampler);
    EXPECT_EQ(setLayouts[2].layout.bindingCount, 1u);
    EXPECT_FALSE(setLayouts[2].usesPerObject);
    EXPECT_FALSE(setLayouts[2].usesMaterial);
    EXPECT_TRUE(setLayouts[2].usesTexture);
    EXPECT_FALSE(setLayouts[2].usesSampler);
    EXPECT_TRUE(setLayouts[2].shaderVisible);
    EXPECT_EQ(setLayouts[3].layout.bindingCount, 1u);
    EXPECT_FALSE(setLayouts[3].usesPerObject);
    EXPECT_FALSE(setLayouts[3].usesMaterial);
    EXPECT_FALSE(setLayouts[3].usesTexture);
    EXPECT_TRUE(setLayouts[3].usesSampler);
    EXPECT_TRUE(setLayouts[3].shaderVisible);
    EXPECT_EQ(setLayouts[3].heapType, DescriptorHeapType::Sampler);

    delete shader;
}

TEST(BuiltinPassLayout_Test, BuildsSharedSetLayoutsFromBuiltinShadowCasterShaderContract) {
    ShaderLoader loader;
    LoadResult result = loader.Load(GetBuiltinShadowCasterShaderPath());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Shader* shader = static_cast<Shader*>(result.resource);
    ASSERT_NE(shader, nullptr);

    const ShaderPass* pass = shader->FindPass("ShadowCaster");
    ASSERT_NE(pass, nullptr);

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    ASSERT_TRUE(TryBuildBuiltinPassResourceBindingPlan(*pass, plan, &error)) << error.CStr();
    EXPECT_TRUE(plan.perObject.IsValid());
    EXPECT_TRUE(plan.material.IsValid());
    EXPECT_TRUE(plan.baseColorTexture.IsValid());
    EXPECT_TRUE(plan.linearClampSampler.IsValid());
    EXPECT_EQ(plan.firstDescriptorSet, 0u);
    EXPECT_EQ(plan.descriptorSetCount, 4u);
    EXPECT_TRUE(plan.usesConstantBuffers);
    EXPECT_TRUE(plan.usesTextures);
    EXPECT_TRUE(plan.usesSamplers);

    std::vector<BuiltinPassSetLayoutMetadata> setLayouts;
    ASSERT_TRUE(TryBuildBuiltinPassSetLayouts(plan, setLayouts, &error)) << error.CStr();
    ASSERT_EQ(setLayouts.size(), 4u);
    EXPECT_EQ(setLayouts[0].layout.bindingCount, 1u);
    EXPECT_TRUE(setLayouts[0].usesPerObject);
    EXPECT_FALSE(setLayouts[0].usesMaterial);
    EXPECT_FALSE(setLayouts[0].usesTexture);
    EXPECT_FALSE(setLayouts[0].usesSampler);
    EXPECT_EQ(setLayouts[1].layout.bindingCount, 1u);
    EXPECT_FALSE(setLayouts[1].usesPerObject);
    EXPECT_TRUE(setLayouts[1].usesMaterial);
    EXPECT_FALSE(setLayouts[1].usesTexture);
    EXPECT_FALSE(setLayouts[1].usesSampler);
    EXPECT_EQ(setLayouts[2].layout.bindingCount, 1u);
    EXPECT_FALSE(setLayouts[2].usesPerObject);
    EXPECT_FALSE(setLayouts[2].usesMaterial);
    EXPECT_TRUE(setLayouts[2].usesTexture);
    EXPECT_FALSE(setLayouts[2].usesSampler);
    EXPECT_TRUE(setLayouts[2].shaderVisible);
    EXPECT_EQ(setLayouts[3].layout.bindingCount, 1u);
    EXPECT_FALSE(setLayouts[3].usesPerObject);
    EXPECT_FALSE(setLayouts[3].usesMaterial);
    EXPECT_FALSE(setLayouts[3].usesTexture);
    EXPECT_TRUE(setLayouts[3].usesSampler);
    EXPECT_TRUE(setLayouts[3].shaderVisible);
    EXPECT_EQ(setLayouts[3].heapType, DescriptorHeapType::Sampler);

    delete shader;
}

TEST(BuiltinPassLayout_Test, RejectsMixedSamplerAndNonSamplerBindingsInOneSet) {
    Array<ShaderResourceBindingDesc> bindings;
    bindings.Resize(2);

    bindings[0].name = "BaseColorTexture";
    bindings[0].type = ShaderResourceType::Texture2D;
    bindings[0].set = 0;
    bindings[0].binding = 0;
    bindings[0].semantic = "BaseColorTexture";

    bindings[1].name = "LinearClampSampler";
    bindings[1].type = ShaderResourceType::Sampler;
    bindings[1].set = 0;
    bindings[1].binding = 1;
    bindings[1].semantic = "LinearClampSampler";

    BuiltinPassResourceBindingPlan plan = {};
    String error;
    ASSERT_TRUE(TryBuildBuiltinPassResourceBindingPlan(bindings, plan, &error)) << error.CStr();

    std::vector<BuiltinPassSetLayoutMetadata> setLayouts;
    EXPECT_FALSE(TryBuildBuiltinPassSetLayouts(plan, setLayouts, &error));
    EXPECT_EQ(error, "Builtin pass does not support mixing sampler and non-sampler bindings in one set");
}

TEST(BuiltinPassLayout_Test, RejectsDuplicateBindingsInOneSet) {
    BuiltinPassResourceBindingPlan plan = {};
    BuiltinPassResourceBindingDesc perObjectBinding = {};
    perObjectBinding.semantic = BuiltinPassResourceSemantic::PerObject;
    perObjectBinding.resourceType = ShaderResourceType::ConstantBuffer;
    perObjectBinding.location = { 0, 0 };
    plan.bindings.PushBack(perObjectBinding);

    BuiltinPassResourceBindingDesc materialBinding = {};
    materialBinding.semantic = BuiltinPassResourceSemantic::Material;
    materialBinding.resourceType = ShaderResourceType::ConstantBuffer;
    materialBinding.location = { 0, 0 };
    plan.bindings.PushBack(materialBinding);
    plan.maxSetIndex = 0;
    plan.firstDescriptorSet = 0;
    plan.descriptorSetCount = 1;
    plan.usesConstantBuffers = true;
    plan.perObject = { 0, 0 };
    plan.material = { 0, 0 };

    std::vector<BuiltinPassSetLayoutMetadata> setLayouts;
    String error;
    EXPECT_FALSE(TryBuildBuiltinPassSetLayouts(plan, setLayouts, &error));
    EXPECT_EQ(error, "Builtin pass encountered duplicate bindings inside one descriptor set");
}

TEST(BuiltinDepthOnlyPass_Test, UsesFloat3PositionInputLayoutForStaticMeshVertices) {
    const InputLayoutDesc inputLayout = BuiltinDepthOnlyPass::BuildInputLayout();

    ASSERT_EQ(inputLayout.elements.size(), 3u);
    EXPECT_EQ(inputLayout.elements[0].semanticName, "POSITION");
    EXPECT_EQ(inputLayout.elements[1].semanticName, "NORMAL");
    EXPECT_EQ(inputLayout.elements[2].semanticName, "TEXCOORD");
    EXPECT_EQ(inputLayout.elements[0].alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, position)));
    EXPECT_EQ(inputLayout.elements[1].alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, normal)));
    EXPECT_EQ(inputLayout.elements[2].alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, uv0)));
}

TEST(BuiltinShadowCasterPass_Test, UsesFloat3PositionInputLayoutForStaticMeshVertices) {
    const InputLayoutDesc inputLayout = BuiltinShadowCasterPass::BuildInputLayout();

    ASSERT_EQ(inputLayout.elements.size(), 3u);
    EXPECT_EQ(inputLayout.elements[0].semanticName, "POSITION");
    EXPECT_EQ(inputLayout.elements[1].semanticName, "NORMAL");
    EXPECT_EQ(inputLayout.elements[2].semanticName, "TEXCOORD");
    EXPECT_EQ(inputLayout.elements[0].alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, position)));
    EXPECT_EQ(inputLayout.elements[1].alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, normal)));
    EXPECT_EQ(inputLayout.elements[2].alignedByteOffset, static_cast<uint32_t>(offsetof(StaticMeshVertex, uv0)));
}