Enable shared library linking for open3d*.wheel

CMakeLists.txt

@@ -45,6 +45,7 @@ option(BUILD_SHARED_LIBS          "Build shared libraries"                   OFF
 option(BUILD_EXAMPLES             "Build Open3D examples programs"           ON )
 option(BUILD_UNIT_TESTS           "Build Open3D unit tests"                  OFF)
 option(BUILD_BENCHMARKS           "Build the micro benchmarks"               OFF)
+option(BUILD_APPS                 "Build the Open3D Applications"            OFF)
 option(BUILD_PYTHON_MODULE        "Build the python module"                  ON )
 option(BUILD_CUDA_MODULE          "Build the CUDA module"                    OFF)
 option(BUILD_COMMON_CUDA_ARCHS    "Build for common CUDA GPUs (for release)" OFF)
@@ -141,6 +142,23 @@ if (NOT DEVELOPER_BUILD)
     endif()
 endif()
 
+if(UNIX)
+    if(APPLE)
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -w")
+        set(CMAKE_MACOSX_RPATH ON)
+        set(_rpath_portable_origin "@loader_path/../lib")
+    else()
+        set(_rpath_portable_origin $ORIGIN/../lib)
+    endif()
+    # Use separate rpaths during build and install phases.
+    set(CMAKE_SKIP_BUILD_RPATH FALSE)
+    # Don't use the install-rpath during the build phase.
+    set(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE)
+    set(CMAKE_INSTALL_RPATH "${_rpath_portable_origin}")
+    set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
+endif()
+message(STATUS "CMAKE_INSTALL_RPATH: " ${CMAKE_INSTALL_RPATH})
+
 # Default build type on single-config generators.
 # For multi-config generators (e.g. Visual Studio), CMAKE_CONFIGURATION_TYPES
 # will be set, and we don't specify a default CMAKE_BUILD_TYPE.

cmake/Open3DPrintConfigurationSummary.cmake

@@ -36,6 +36,7 @@ function(open3d_print_configuration_summary)
     endif()
     open3d_aligned_print("Build Unit Tests" "${BUILD_UNIT_TESTS}")
     open3d_aligned_print("Build Examples" "${BUILD_EXAMPLES}")
+    open3d_aligned_print("Build Applications" "${BUILD_APPS}")
     open3d_aligned_print("Build Python Module" "${BUILD_PYTHON_MODULE}")
     open3d_aligned_print("Build Jupyter Extension" "${BUILD_JUPYTER_EXTENSION}")
     open3d_aligned_print("Build TensorFlow Ops" "${BUILD_TENSORFLOW_OPS}")

cpp/CMakeLists.txt

@@ -1,6 +1,8 @@
 add_subdirectory(open3d)
 add_subdirectory(tools)
-add_subdirectory(apps)
+if(BUILD_APPS)
+    add_subdirectory(apps)
+endif()
 if (BUILD_UNIT_TESTS)
     add_subdirectory(tests)
 endif()

cpp/pybind/CMakeLists.txt

@@ -181,6 +181,16 @@ if (BUNDLE_OPEN3D_ML)
     list(APPEND GENERATED_OUTPUTS open3d_ml)
 endif()
 
+# pybind*.so must be install to change the rpath such that it can find the 
+# installed libOpen3D.so after install to python environment.
+if (BUILD_SHARED_LIBS)
+    set(BUILD_TYPE "cpu")
+    if(BUILD_CUDA_MODULE)
+        set(BUILD_TYPE "cuda")
+    endif()
+    install(TARGETS pybind DESTINATION ${PYTHON_PACKAGE_DST_DIR}/open3d/${BUILD_TYPE})
+endif()
+
 configure_file("_build_config.py.in"
                "${CMAKE_BINARY_DIR}/lib/_build_config.py.in")
 file(GENERATE
@@ -212,6 +222,9 @@ add_custom_target(python-package
             -DPROJECT_VERSION_THREE_NUMBER=${PROJECT_VERSION_THREE_NUMBER}
             -DPYPI_PACKAGE_NAME=${PYPI_PACKAGE_NAME}
             -P ${CMAKE_CURRENT_SOURCE_DIR}/make_python_package.cmake
+    COMMAND ${CMAKE_COMMAND} --install
+            ${CMAKE_BINARY_DIR} 
+            --prefix ${PYTHON_PACKAGE_DST_DIR}/open3d
     VERBATIM
     DEPENDS ${GENERATED_OUTPUTS}
 )