Method ApproximateAreaLight

Hydrogent/src/HnLight.cpp:307–356

bool HnLight::ApproximateAreaLight(pxr::HdSceneDelegate& SceneDelegate, float MetersPerUnit)
{
    bool ParamsDirty = false;

    const pxr::SdfPath& Id = GetId();

    // Light color
    {
        const float3 Color = GetLightColor(SceneDelegate, Id);
        if (Color != m_Params.Color)
        {
            m_Params.Color = Color;
            ParamsDirty    = true;
        }
    }

    // Light intensity
    {
        float Intensity    = GetLightIntensity(SceneDelegate, Id);
        float ExposedPower = GetLightExposedPower(SceneDelegate, Id);
        Intensity *= ExposedPower;

        pxr::VtValue NormalizeVal = SceneDelegate.GetLightParamValue(Id, pxr::HdLightTokens->normalize);
        if (!NormalizeVal.GetWithDefault<bool>(false))
        {
            float LightArea = GetLightArea(SceneDelegate, Id, m_TypeId, MetersPerUnit);
            Intensity *= LightArea;
        }

        if (Intensity != m_Params.Intensity)
        {
            m_Params.Intensity = Intensity;
            ParamsDirty        = true;
        }
    }

    if (m_TypeId == pxr::HdPrimTypeTokens->rectLight ||
        m_TypeId == pxr::HdPrimTypeTokens->diskLight)
    {
        float ShapingConeAngle = GetShapingConeAngle(SceneDelegate, Id);
        if (ShapingConeAngle != m_Params.OuterConeAngle)
        {
            m_Params.InnerConeAngle = 0;
            m_Params.OuterConeAngle = ShapingConeAngle;
            ParamsDirty             = true;
        }
    }

    return ParamsDirty;
}

static pxr::SdfAssetPath GetTextureFile(pxr::HdSceneDelegate& SceneDelegate, const pxr::SdfPath& Id)
{