体验思维驱动：车载 HMI 3D 交互的工程化实践¶

// [AI补充] 延迟渲染管线的核心配置
void FDeferredShadingSceneRenderer::Render(FRHICommandListImmediate& RHICmdList)
{
    // 1. 几何通道：渲染场景几何到 G-Buffer
    RenderBasePass(RHICmdList);

    // 2. 光照通道：基于 G-Buffer 计算光照
    RenderLights(RHICmdList);

    // 3. 后处理：应用 Bloom、色调映射等效果
    RenderPostProcessing(RHICmdList);
}

// 动态阴影精度调整
FProjectedShadowInfo::SetupProjection()
{
    // 根据距离动态调整阴影贴图分辨率
    float ShadowResolutionScale = FMath::Clamp(
        1.0f / (Distance * 0.01f), 
        MinResolutionScale, 
        MaxResolutionScale
    );
}

// [AI补充] 玻璃着色器的核心逻辑
float4 GlassShader(FMaterialPixelParameters Parameters)
{
    // 1. 获取场景深度
    float SceneDepth = CalcSceneDepth(Parameters.ScreenPosition);

    // 2. 计算折射偏移
    float2 RefractionOffset = Parameters.WorldNormal.xy * RefractionStrength;
    float2 RefractUV = Parameters.ScreenPosition.xy + RefractionOffset;

    // 3. 采样场景颜色
    float3 SceneColor = SceneTextureLookup(RefractUV, SceneDepth);

    // 4. 混合玻璃颜色
    float3 FinalColor = lerp(SceneColor, GlassColor, GlassOpacity);

    return float4(FinalColor, 1.0);
}

// [AI补充] 智能调色器的实现逻辑
float3 AdaptiveToneMapping(float3 HDRColor, float AmbientLight)
{
    // 1. 根据环境光强度动态调整曝光
    float Exposure = lerp(MinExposure, MaxExposure, AmbientLight);

    // 2. 应用 ACES 色调映射
    float3 ACESColor = ACESFilm(HDRColor * Exposure);

    // 3. 增强暗部细节
    float3 ShadowBoost = pow(ACESColor, 1.0 / ShadowGamma);

    return lerp(ACESColor, ShadowBoost, ShadowBoostStrength);
}

// [AI补充] 粒子系统热管理脚本
void UParticleThermalManager::Tick(float DeltaTime)
{
    // 1. 读取芯片温度
    float ChipTemperature = GetChipTemperature();

    // 2. 根据温度调整粒子数量
    if (ChipTemperature > HighTempThreshold)
    {
        ParticleSystem->SetSpawnRate(LowSpawnRate);
    }
    else if (ChipTemperature < NormalTempThreshold)
    {
        ParticleSystem->SetSpawnRate(NormalSpawnRate);
    }
}

// [AI补充] 视差遮蔽贴图的着色器实现
float2 ParallaxOcclusionMapping(float2 UV, float3 ViewDir, sampler2D HeightMap)
{
    // 1. 设置采样层数
    const int NumLayers = 32;
    float LayerDepth = 1.0 / NumLayers;

    // 2. 计算每层的 UV 偏移
    float2 DeltaUV = ViewDir.xy * HeightScale / (ViewDir.z * NumLayers);

    // 3. 迭代查找交点
    float CurrentLayerDepth = 0.0;
    float2 CurrentUV = UV;
    float CurrentHeight = tex2D(HeightMap, CurrentUV).r;

    while(CurrentLayerDepth < CurrentHeight)
    {
        CurrentUV -= DeltaUV;
        CurrentHeight = tex2D(HeightMap, CurrentUV).r;
        CurrentLayerDepth += LayerDepth;
    }

    return CurrentUV;
}

// [AI补充] 地形材质混合的优化实现
float3 BlendTerrainMaterials(float4 VertexColor, float2 UV)
{
    // 1. 从顶点颜色读取权重
    float WeightGrass = VertexColor.r;
    float WeightRock = VertexColor.g;
    float WeightSand = VertexColor.b;
    float WeightSnow = VertexColor.a;

    // 2. 采样各层材质
    float3 ColorGrass = tex2D(GrassTexture, UV).rgb;
    float3 ColorRock = tex2D(RockTexture, UV).rgb;
    float3 ColorSand = tex2D(SandTexture, UV).rgb;
    float3 ColorSnow = tex2D(SnowTexture, UV).rgb;

    // 3. 线性混合（优化后的公式）
    float3 FinalColor = ColorGrass * WeightGrass +
                        ColorRock * WeightRock +
                        ColorSand * WeightSand +
                        ColorSnow * WeightSnow;

    return FinalColor;
}

// [AI补充] 独立动画线程的实现
class FAnimationWorkerThread : public FRunnable
{
public:
    virtual uint32 Run() override
    {
        while (!bShouldStop)
        {
            // 1. 从队列获取动画任务
            FAnimationTask Task;
            if (TaskQueue.Dequeue(Task))
            {
                // 2. 在独立线程计算动画
                Task.AnimInstance->UpdateAnimation(DeltaTime);

                // 3. 将结果同步回主线程
                FinalPoseQueue.Enqueue(Task.AnimInstance->GetFinalPose());
            }
        }
        return 0;
    }
};

// [AI补充] Gerstner 波的顶点着色器实现
float3 GerstnerWave(float3 Position, float Time)
{
    float3 Offset = float3(0, 0, 0);

    // 多个波的叠加
    for (int i = 0; i < NumWaves; i++)
    {
        float Frequency = Waves[i].Frequency;
        float Amplitude = Waves[i].Amplitude;
        float2 Direction = Waves[i].Direction;

        float Phase = dot(Direction, Position.xy) * Frequency + Time;

        Offset.x += Direction.x * Amplitude * cos(Phase);
        Offset.y += Direction.y * Amplitude * cos(Phase);
        Offset.z += Amplitude * sin(Phase);
    }

    return Position + Offset;
}

// [AI补充] 探针混合反射的实现
float3 BlendedReflection(float3 WorldPosition, float3 ViewDir)
{
    // 1. 查找最近的反射探针
    FReflectionProbe Probe1 = FindNearestProbe(WorldPosition);
    FReflectionProbe Probe2 = FindSecondNearestProbe(WorldPosition);

    // 2. 采样探针立方体贴图
    float3 Reflection1 = texCUBE(Probe1.CubemapTexture, ViewDir).rgb;
    float3 Reflection2 = texCUBE(Probe2.CubemapTexture, ViewDir).rgb;

    // 3. 根据距离混合
    float BlendWeight = saturate(distance(WorldPosition, Probe1.Position) / BlendRadius);
    float3 ProbeReflection = lerp(Reflection1, Reflection2, BlendWeight);

    // 4. 与屏幕空间反射混合
    float3 SSRReflection = ScreenSpaceReflection(WorldPosition, ViewDir);
    float SSRMask = GetSSRMask(WorldPosition);

    return lerp(ProbeReflection, SSRReflection, SSRMask);
}

// [AI补充] 程序化道路生成的实现
void UProceduralRoadGenerator::GenerateRoad(const FMapData& MapData)
{
    // 1. 从地图数据创建样条线
    USplineComponent* RoadSpline = CreateSplineFromMapData(MapData);

    // 2. 沿样条线生成道路网格
    for (float Distance = 0; Distance < RoadSpline->GetSplineLength(); Distance += SegmentLength)
    {
        FVector Location = RoadSpline->GetLocationAtDistanceAlongSpline(Distance, ESplineCoordinateSpace::World);
        FRotator Rotation = RoadSpline->GetRotationAtDistanceAlongSpline(Distance, ESplineCoordinateSpace::World);

        // 生成道路片段
        UStaticMeshComponent* RoadSegment = CreateRoadSegment(Location, Rotation);

        // 清除与道路重叠的物体
        RemoveOverlappingObjects(RoadSegment);
    }

    // 3. 随机分布路边装饰物
    DistributeRoadsideObjects(RoadSpline);
}

// 随机分布装饰物
void UProceduralRoadGenerator::DistributeRoadsideObjects(USplineComponent* Spline)
{
    for (int i = 0; i < NumObjects; i++)
    {
        float Distance = FMath::RandRange(0.0f, Spline->GetSplineLength());
        FVector Location = Spline->GetLocationAtDistanceAlongSpline(Distance, ESplineCoordinateSpace::World);

        // 随机偏移、旋转和缩放
        Location += FMath::VRand() * RandomOffset;
        FRotator Rotation = FRotator(0, FMath::RandRange(0.0f, 360.0f), 0);
        float Scale = FMath::RandRange(MinScale, MaxScale);

        SpawnDecoration(Location, Rotation, Scale);
    }
}