CMake區分MSVC版本

MSVC++ 4.x _MSC_VER == 1000 MSVC++ 5.0 _MSC_VER == 1100 MSVC++ 6.0 _MSC_VER == 1200 MSVC++ 7.0 _MSC_VER == 1300 MSVC++ 7.1 _MSC_VER == 1310 (Visual Studio 2003) MSVC++ 8.0 _MSC_VER == 1400 (Visual Studio 2005) MSVC++ 9.0 _MSC_VER == 1500 (Visual Studio 2008) MSVC++ 10.0 _MSC_VER == 1600 (Visual Studio 2010) MSVC++ 11.0 _MSC_VER == 1700 (Visual Studio 2012) MSVC++ 12.0 _MSC_VER == 1800 (Visual Studio 2013) MSVC++ 14.0 _MSC_VER == 1900 (Visual Studio 2015) MSVC++ 14.1 _MSC_VER == 1911 (Visual Studio 2017)

if(MSVC)
  if(CMAKE_CL_64)
    set(OpenCV_ARCH x64)
    set(OpenCV_TBB_ARCH intel64)
  else()
    set(OpenCV_ARCH x86)
    set(OpenCV_TBB_ARCH ia32)
  endif()
  if(MSVC_VERSION EQUAL 1400)
    set(OpenCV_RUNTIME vc8)
  elseif(MSVC_VERSION EQUAL 1500)
    set(OpenCV_RUNTIME vc9)
  elseif(MSVC_VERSION EQUAL 1600)
    set(OpenCV_RUNTIME vc10)
  elseif(MSVC_VERSION EQUAL 1700)
    set(OpenCV_RUNTIME vc11)
  elseif(MSVC_VERSION EQUAL 1800)
    set(OpenCV_RUNTIME vc12)
  elseif(MSVC_VERSION EQUAL 1900)
    set(OpenCV_RUNTIME vc14)
  endif()