ENH: prepare a standalone project to compile bindings

Modules/Wrappers/SWIG/src/python/CMakeLists.txt

@@ -87,3 +87,20 @@ if(PYTHON_VERSION_STRING VERSION_LESS "3.2.0")
 else()
   # TODO : pyc file is in a subfolder.
 endif()
+
+configure_file(StandaloneWrapper.in CMakeLists.txt @ONLY)
+
+install( FILES ${CMAKE_SWIG_OUTDIR}/otbApplicationPYTHON_wrap.cxx
+               ${CMAKE_SWIG_OUTDIR}/otbApplicationPYTHON_wrap.h
+               itkPyCommand.cxx
+               itkPyCommand.h
+               otbPythonLogOutput.cxx
+               otbPythonLogOutput.h
+               otbSwigPrintCallback.h
+               otbProgressReporterManager.cxx
+               otbProgressReporterManager.h
+               ../itkBase.includes
+               ../otbWrapperSWIGIncludes.h
+               ${CMAKE_CURRENT_BINARY_DIR}/CMakeLists.txt
+         DESTINATION ${OTB_INSTALL_DATA_DIR}/swig
+         COMPONENT Resources )

Modules/Wrappers/SWIG/src/python/StandaloneWrapper.in

+cmake_minimum_required(VERSION 3.10.1)
+project(OTBPythonWrappers)
+
+get_filename_component(PKG_PREFIX "${CMAKE_CURRENT_SOURCE_DIR}" PATH)
+get_filename_component(PKG_PREFIX "${PKG_PREFIX}" PATH)
+get_filename_component(PKG_PREFIX "${PKG_PREFIX}" PATH)
+
+find_package(OTB REQUIRED HINTS ${PKG_PREFIX}/@OTB_INSTALL_PACKAGE_DIR@)
+list(APPEND CMAKE_MODULE_PATH ${OTB_CMAKE_DIR})
+include(${OTB_USE_FILE})
+
+set ( Python_ADDITIONAL_VERSIONS "3;2" )
+set ( PythonInterp_FIND_REQUIRED ${OTB_WRAP_PYTHON} )
+set ( PythonLibs_FIND_REQUIRED ${OTB_WRAP_PYTHON} )
+find_package( PythonInterp )
+if ( OTB_WRAP_PYTHON AND ( ${PYTHON_VERSION_MAJOR} EQUAL 2 ) )
+    message (WARNING "Python3 not found. There is no longer support of \
+    wrapping in python2 in OTB, but it can still be used.")
+endif()
+# Now that we have a python version the addditional versions should only
+# contain the version we have to get the corresponding libs
+set (Python_ADDITIONAL_VERSIONS "${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR}")
+find_package ( PythonLibs )
+include_directories(${PYTHON_INCLUDE_DIR})
+
+find_package(Numpy)
+if ( NUMPY_FOUND )
+  include_directories(${NUMPY_INCLUDE_DIRS})
+else()
+  message( WARNING 
+    "OTB wrappers will be done without support for NumPy (not found).")
+endif()
+
+include_directories("${CMAKE_CURRENT_SOURCE_DIR}")
+
+file(GLOB OTBPythonWrappers_SOURCES "*.cxx")
+
+# declare the python wrapper library
+add_library(PythonWrapperLib MODULE ${OTBPythonWrappers_SOURCES})
+target_link_libraries(PythonWrapperLib ${PYTHON_LIBRARIES} OTBApplicationEngine)
+
+set_target_properties(PythonWrapperLib PROPERTIES
+  OUTPUT_NAME   "_otbApplication"
+  NO_SONAME     ON
+  PREFIX        "")
+
+if(WIN32 AND NOT CYGWIN)
+  set_target_properties(PythonWrapperLib PROPERTIES SUFFIX ".pyd")
+endif()
+
+if(NUMPY_FOUND)
+  add_definitions(-DOTB_SWIGNUMPY=1)
+endif()
+
+install(TARGETS PythonWrapperLib
+        DESTINATION lib/python
+        COMPONENT RuntimeLibraries )

Packaging/install_python_bindings.cmake

@@ -24,6 +24,9 @@ function(install_python_bindings)
       PATTERN "*.pyc" EXCLUDE
       PATTERN "__pycache__" EXCLUDE
       )
+    install(DIRECTORY ${SUPERBUILD_INSTALL_DIR}/share/otb/swig
+      DESTINATION ${PKG_STAGE_DIR}/share/otb
+      )
   endif()
   # Handle GDAL python bindings
   file(GLOB gdal_python_scripts "${SUPERBUILD_INSTALL_DIR}/bin/gdal*.py")