Merge pull request #13001 from rgarnov:gapi_standalone_cmake

modules/gapi/CMakeLists.txt

+# FIXME: Rework standalone build in more generic maner
+# (Restructure directories, add common pass, etc)
+if (NOT DEFINED OPENCV_INITIAL_PASS)
+    include("cmake/standalone.cmake")
+    return()
+endif()
+
 # FIXME: Remove CXX11 check after complete switch to OpenCV 4 branch
 # (CI, bundle, workloads, etc)
 if (NOT HAVE_CXX11 OR NOT TARGET ade)

modules/gapi/cmake/standalone.cmake

+if (NOT TARGET ade )
+  find_package(ade 0.1.0 REQUIRED)
+endif()
+
+set(FLUID_TARGET fluid)
+set(FLUID_ROOT "${CMAKE_CURRENT_LIST_DIR}/../")
+
+file(GLOB FLUID_includes "${FLUID_ROOT}/include/opencv2/*.hpp"
+                         "${FLUID_ROOT}/include/opencv2/gapi/g*.hpp"
+                         "${FLUID_ROOT}/include/opencv2/gapi/util/*.hpp"
+                         "${FLUID_ROOT}/include/opencv2/gapi/own/*.hpp"
+                         "${FLUID_ROOT}/include/opencv2/gapi/fluid/*.hpp")
+file(GLOB FLUID_sources  "${FLUID_ROOT}/src/api/g*.cpp"
+                         "${FLUID_ROOT}/src/compiler/*.cpp"
+                         "${FLUID_ROOT}/src/compiler/passes/*.cpp"
+                         "${FLUID_ROOT}/src/executor/*.cpp"
+                         "${FLUID_ROOT}/src/backends/fluid/*.cpp"
+                         "${FLUID_ROOT}/src/backends/common/*.cpp")
+
+add_library(${FLUID_TARGET} STATIC ${FLUID_includes} ${FLUID_sources})
+
+target_include_directories(${FLUID_TARGET}
+  PUBLIC          $<BUILD_INTERFACE:${FLUID_ROOT}/include>
+  PRIVATE         ${FLUID_ROOT}/src)
+
+target_compile_definitions(${FLUID_TARGET} PUBLIC -DGAPI_STANDALONE
+# This preprocessor definition resolves symbol clash when
+# standalone fluid meets gapi ocv module in one application
+                                           PUBLIC cv=fluidcv)
+
+set_target_properties(${FLUID_TARGET} PROPERTIES POSITION_INDEPENDENT_CODE True)
+set_property(TARGET ${FLUID_TARGET} PROPERTY CXX_STANDARD 11)
+
+target_link_libraries(${FLUID_TARGET} PRIVATE ade)