PR #8176 from Nir: Clone pybind11 V2.6.1 as part of CMake

third-party/pybind11/CMakeLists.txt

@@ -0,0 +1,20 @@
+#  minimum required cmake version: 3.1.0
+cmake_minimum_required(VERSION 3.1.0)
+
+project(pybind11-download NONE)
+
+include(ExternalProject)
+ExternalProject_Add(
+        pybind11
+        PREFIX .
+        GIT_REPOSITORY "https://github.com/pybind/pybind11.git"
+        GIT_TAG "f1abf5d9159b805674197f6bc443592e631c9130" # v2.6.1
+        SOURCE_DIR "${CMAKE_BINARY_DIR}/third-party/pybind11"
+        # Override default steps with no action, we just want the clone step.
+        UPDATE_COMMAND ""       
+        CONFIGURE_COMMAND ""
+        BUILD_COMMAND ""
+        INSTALL_COMMAND ""
+)
+
+

wrappers/CMakeLists.txt

@@ -6,7 +6,11 @@ project(RealsenseWrappers)
 set(DEPENDENCIES realsense2)
 
 if (BUILD_PYTHON_BINDINGS OR BUILD_PYTHON_DOCS)
-  add_subdirectory(python)
+    if (NOT INTERNET_CONNECTION)
+        message(WARNING "No internet connection. Cloning Python bindings may fail")
+    endif()
+    add_subdirectory(python)        
+
 endif()
 
 if (BUILD_NODEJS_BINDINGS)

wrappers/python/CMakeLists.txt

@@ -7,20 +7,25 @@ if (NOT BUILD_PYTHON_BINDINGS)
     message(WARNING "Python Bindings being built despite unset option because they are required for python documentation")
 endif()
 
-if (CMAKE_VERSION VERSION_LESS 3.12)
-  find_package(PythonInterp REQUIRED)
-  find_package(PythonLibs REQUIRED)
-  set(PYTHON_INSTALL_DIR "${CMAKE_INSTALL_LIBDIR}/python${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR}/pyrealsense2" CACHE PATH "Installation directory for Python bindings")
-  set(CMAKECONFIG_PY_INSTALL_DIR "${CMAKE_INSTALL_LIBDIR}/cmake/pyrealsense2")
-else()
-  find_package(Python REQUIRED COMPONENTS Interpreter Development)
-  set(PYTHON_INSTALL_DIR "${Python_SITEARCH}/pyrealsense2" CACHE PATH "Installation directory for Python bindings")
-  set(CMAKECONFIG_PY_INSTALL_DIR "${CMAKE_INSTALL_LIBDIR}/cmake/pyrealsense2")
-endif()
-
 set(DEPENDENCIES realsense2)
+# In order for the external project clone to occur during cmake configure step(rather than during compilation, as would normally happen),
+# we copy the external project declaration to the build folder and then execute it
+configure_file(${CMAKE_SOURCE_DIR}/third-party/pybind11/CMakeLists.txt ${CMAKE_BINARY_DIR}/external-projects/pybind11/CMakeLists.txt)
+execute_process(COMMAND "${CMAKE_COMMAND}" -G "${CMAKE_GENERATOR}" .
+    WORKING_DIRECTORY "${CMAKE_BINARY_DIR}/external-projects/pybind11"
+)
+execute_process(COMMAND "${CMAKE_COMMAND}" --build .
+    WORKING_DIRECTORY "${CMAKE_BINARY_DIR}/external-projects/pybind11"
+)
 
-add_subdirectory(third_party/pybind11)
+# Add pybind11 makefile
+add_subdirectory("${CMAKE_BINARY_DIR}/third-party/pybind11"
+                 "${CMAKE_BINARY_DIR}/third-party/pybind11"
+                 EXCLUDE_FROM_ALL
+)
+
+set(PYBIND11_CPP_STANDARD -std=c++11)
+include_directories(${CMAKE_BINARY_DIR}/third-party/pybind11/include)
 
 set(PYRS_CPP
     python.cpp
@@ -41,6 +46,20 @@ set(PYRS_CPP
 )
 
 pybind11_add_module(pyrealsense2 SHARED python.hpp ${PYRS_CPP})
+
+# pybind11 version 2.6.1 require find_package to run after pybind11_add_module call,
+# This way the pybind takes the python version set in PYTHON_EXECUTABLE variable.
+if (CMAKE_VERSION VERSION_LESS 3.12)
+  find_package(PythonInterp REQUIRED)
+  find_package(PythonLibs REQUIRED)
+  set(PYTHON_INSTALL_DIR "${CMAKE_INSTALL_LIBDIR}/python${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR}/pyrealsense2" CACHE PATH "Installation directory for Python bindings")
+  set(CMAKECONFIG_PY_INSTALL_DIR "${CMAKE_INSTALL_LIBDIR}/cmake/pyrealsense2")
+else()
+  find_package(Python REQUIRED COMPONENTS Interpreter Development)
+  set(PYTHON_INSTALL_DIR "${Python_SITEARCH}/pyrealsense2" CACHE PATH "Installation directory for Python bindings")
+  set(CMAKECONFIG_PY_INSTALL_DIR "${CMAKE_INSTALL_LIBDIR}/cmake/pyrealsense2")
+endif()
+
 target_link_libraries(pyrealsense2 PRIVATE ${DEPENDENCIES})
 set_target_properties(pyrealsense2 PROPERTIES VERSION
     ${REALSENSE_VERSION_STRING} SOVERSION "${REALSENSE_VERSION_MAJOR}.${REALSENSE_VERSION_MINOR}")