Building with a pre-installed pybind11

[jfpanisset]

In the top-level CMakeLists.txt there are currently CMake variables to use find_package() and skip using the vendored copies of imath and rapidjson:

option(OTIO_FIND_IMATH                "Find Imath using find_package" OFF)
option(OTIO_FIND_RAPIDJSON            "Find RapidJSON using find_package" OFF)

As part of creating a Conan recipe for the aswf-docker project,
I would also like to skip the vendored copy of pybind11 and let CMake find the one I provide.

The following patch against 0.18.1 seems to do the trick, but since I am very new to building OTIO (and I'm not an end user), I may be missing
some context to evaluate whether this is correct. If it is, I'm happy to submit the patch as a PR.

diff --git CMakeLists.txt CMakeLists.txt
index d99dd79ac..bfda2778a 100644
--- CMakeLists.txt
+++ CMakeLists.txt
@@ -32,6 +32,7 @@
 option(OTIO_INSTALL_PYTHON_MODULES    "Install OTIO pure Python modules/files" ON)
 option(OTIO_INSTALL_COMMANDLINE_TOOLS "Install the OTIO command line tools" ON)
 option(OTIO_FIND_IMATH                "Find Imath using find_package" OFF)
+option(OTIO_FIND_PYBIND11             "Find pybind11 usnig find_package" OFF)
 option(OTIO_FIND_RAPIDJSON            "Find RapidJSON using find_package" OFF)
 set(OTIO_PYTHON_INSTALL_DIR "" CACHE STRING "Python installation dir (such as the site-packages dir)")

@@ -252,6 +253,17 @@
     include_directories("${PROJECT_SOURCE_DIR}/src/deps/Imath/src")
 endif()

+#----- pybind11
+if(OTIO_FIND_PYBIND11)
+    find_package(pybind11 REQUIRED)
+    if (pybind11_FOUND)
+        message(STATUS "Found pybind11 at ${pybind11_CONFIG}")
+    endif()
+else()
+    message(STATUS "Using src/deps/pybind11 by default")
+endif()
+
+
 #----- RapidJSON

 if(OTIO_FIND_RAPIDJSON)
diff --git src/deps/CMakeLists.txt src/deps/CMakeLists.txt
index d99dd79ac..bfda2778a 100644
--- src/deps/CMakeLists.txt
+++ src/deps/CMakeLists.txt
@@ -4,7 +4,10 @@
 #----- Other dependencies

 # detect if the submodules haven't been updated
-set(DEPS_SUBMODULES pybind11)
+if(NOT OTIO_FIND_PYBIND11 AND OTIO_PYTHON_INSTALL)
+    set(DEPS_SUBMODULES ${DEPS_SUBMODULES} pybind11)
+    add_subdirectory(pybind11)
+endif()

 if(NOT OTIO_FIND_RAPIDJSON)
     set(DEPS_SUBMODULES ${DEPS_SUBMODULES} rapidjson)
@@ -21,10 +24,6 @@
     endif()
 endforeach()

-if(OTIO_PYTHON_INSTALL)
-    add_subdirectory(pybind11)
-endif()
-
 if(NOT OTIO_FIND_IMATH)
     # preserve BUILD_SHARED_LIBS options for this project, but set it off for Imath
     option(BUILD_SHARED_LIBS "Build shared libraries" ON)

[darbyjohnston]

This would be nice to have, if you can make a PR I'll look at it in more detail, thanks.