static void GetSurfaceInfo()

in MiniEngine/Core/DDSTextureLoader.cpp [312:439]

• 119 lines of code
• 40 McCabe index (conditional complexity)

static void GetSurfaceInfo( _In_ size_t width,
                            _In_ size_t height,
                            _In_ DXGI_FORMAT fmt,
                            _Out_opt_ size_t* outNumBytes,
                            _Out_opt_ size_t* outRowBytes,
                            _Out_opt_ size_t* outNumRows )
{
    size_t numBytes = 0;
    size_t rowBytes = 0;
    size_t numRows = 0;

    bool bc = false;
    bool packed = false;
    bool planar = false;
    size_t bpe = 0;
    switch (fmt)
    {
    case DXGI_FORMAT_BC1_TYPELESS:
    case DXGI_FORMAT_BC1_UNORM:
    case DXGI_FORMAT_BC1_UNORM_SRGB:
    case DXGI_FORMAT_BC4_TYPELESS:
    case DXGI_FORMAT_BC4_UNORM:
    case DXGI_FORMAT_BC4_SNORM:
        bc=true;
        bpe = 8;
        break;

    case DXGI_FORMAT_BC2_TYPELESS:
    case DXGI_FORMAT_BC2_UNORM:
    case DXGI_FORMAT_BC2_UNORM_SRGB:
    case DXGI_FORMAT_BC3_TYPELESS:
    case DXGI_FORMAT_BC3_UNORM:
    case DXGI_FORMAT_BC3_UNORM_SRGB:
    case DXGI_FORMAT_BC5_TYPELESS:
    case DXGI_FORMAT_BC5_UNORM:
    case DXGI_FORMAT_BC5_SNORM:
    case DXGI_FORMAT_BC6H_TYPELESS:
    case DXGI_FORMAT_BC6H_UF16:
    case DXGI_FORMAT_BC6H_SF16:
    case DXGI_FORMAT_BC7_TYPELESS:
    case DXGI_FORMAT_BC7_UNORM:
    case DXGI_FORMAT_BC7_UNORM_SRGB:
        bc = true;
        bpe = 16;
        break;

    case DXGI_FORMAT_R8G8_B8G8_UNORM:
    case DXGI_FORMAT_G8R8_G8B8_UNORM:
    case DXGI_FORMAT_YUY2:
        packed = true;
        bpe = 4;
        break;

    case DXGI_FORMAT_Y210:
    case DXGI_FORMAT_Y216:
        packed = true;
        bpe = 8;
        break;

    case DXGI_FORMAT_NV12:
    case DXGI_FORMAT_420_OPAQUE:
        planar = true;
        bpe = 2;
        break;

    case DXGI_FORMAT_P010:
    case DXGI_FORMAT_P016:
        planar = true;
        bpe = 4;
        break;

    }

    if (bc)
    {
        size_t numBlocksWide = 0;
        if (width > 0)
        {
            numBlocksWide = std::max<size_t>( 1, (width + 3) / 4 );
        }
        size_t numBlocksHigh = 0;
        if (height > 0)
        {
            numBlocksHigh = std::max<size_t>( 1, (height + 3) / 4 );
        }
        rowBytes = numBlocksWide * bpe;
        numRows = numBlocksHigh;
        numBytes = rowBytes * numBlocksHigh;
    }
    else if (packed)
    {
        rowBytes = ( ( width + 1 ) >> 1 ) * bpe;
        numRows = height;
        numBytes = rowBytes * height;
    }
    else if ( fmt == DXGI_FORMAT_NV11 )
    {
        rowBytes = ( ( width + 3 ) >> 2 ) * 4;
        numRows = height * 2; // Direct3D makes this simplifying assumption, although it is larger than the 4:1:1 data
        numBytes = rowBytes * numRows;
    }
    else if (planar)
    {
        rowBytes = ( ( width + 1 ) >> 1 ) * bpe;
        numBytes = ( rowBytes * height ) + ( ( rowBytes * height + 1 ) >> 1 );
        numRows = height + ( ( height + 1 ) >> 1 );
    }
    else
    {
        size_t bpp = BitsPerPixel( fmt );
        rowBytes = ( width * bpp + 7 ) / 8; // round up to nearest byte
        numRows = height;
        numBytes = rowBytes * height;
    }

    if (outNumBytes)
    {
        *outNumBytes = numBytes;
    }
    if (outRowBytes)
    {
        *outRowBytes = rowBytes;
    }
    if (outNumRows)
    {
        *outNumRows = numRows;
    }
}