Method execute

Source/Falcor/Utils/Algorithm/ParallelReduction.cpp:76–214

template<typename T>
void ParallelReduction::execute(
    RenderContext* pRenderContext,
    const ref<Texture>& pInput,
    Type operation,
    T* pResult,
    ref<Buffer> pResultBuffer,
    uint64_t resultOffset
)
{
    FALCOR_PROFILE(pRenderContext, "ParallelReduction::execute");

    // Check texture array/mip/sample count.
    if (pInput->getArraySize() != 1 || pInput->getMipCount() != 1 || pInput->getSampleCount() != 1)
    {
        FALCOR_THROW("ParallelReduction::execute() - Input texture is unsupported.");
    }

    // Check texture format.
    uint32_t formatType = FORMAT_TYPE_UNKNOWN;
    switch (getFormatType(pInput->getFormat()))
    {
    case FormatType::Float:
    case FormatType::Unorm:
    case FormatType::Snorm:
        formatType = FORMAT_TYPE_FLOAT;
        break;
    case FormatType::Sint:
        formatType = FORMAT_TYPE_SINT;
        break;
    case FormatType::Uint:
        formatType = FORMAT_TYPE_UINT;
        break;
    default:
        FALCOR_THROW("ParallelReduction::execute() - Input texture format unsupported.");
    }

    // Check that reduction type T is compatible with the resource format.
    if (sizeof(typename T::value_type) != 4 || // The shader is written for 32-bit types
        (formatType == FORMAT_TYPE_FLOAT && !std::is_floating_point<typename T::value_type>::value) ||
        (formatType == FORMAT_TYPE_SINT &&
         (!std::is_integral<typename T::value_type>::value || !std::is_signed<typename T::value_type>::value)) ||
        (formatType == FORMAT_TYPE_UINT &&
         (!std::is_integral<typename T::value_type>::value || !std::is_unsigned<typename T::value_type>::value)))
    {
        FALCOR_THROW("ParallelReduction::execute() - Template type T is not compatible with resource format.");
    }

    uint32_t reductionType = REDUCTION_TYPE_UNKNOWN;
    uint32_t elementSize = 0;
    switch (operation)
    {
    case Type::Sum:
        reductionType = REDUCTION_TYPE_SUM;
        elementSize = 1;
        break;
    case Type::MinMax:
        reductionType = REDUCTION_TYPE_MINMAX;
        elementSize = 2;