Python: install "bpy" as a package WITH_PYTHON_MODULE

Building WITH_PYTHON_MODULE was creating a "bpy" module that required
Blenders data-files to be located in the module search path too.

This mean that a typical installation on Linux would create:

- `/usr/lib/python3.10/site-packages/bpy.so`
- `/usr/lib/python3.10/site-packages/3.4`
  (containing `scripts` & `datafiles`).

The new behavior creates:

- `/usr/lib/python3.10/site-packages/bpy/__init__.so`
- `/usr/lib/python3.10/site-packages/bpy/3.4`

With the advantage that the "bpy" directory is the self contained Python
module.

No changes are needed for the module loading logic as the mechanism to
swap in blend internal Python "bpy" module
(defined in `release/scripts/modules/bpy/__init__.py`)
works the same in both instances.

Thanks to Brecht for macOS support.

Reviewed by brecht

Ref D15911

1 files changed, 4 insertions, 0 deletions

diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index 9521da8417e..b982c69a378 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -659,6 +659,10 @@ if(WITH_PYTHON)
   )
   add_definitions(-DWITH_PYTHON)
 
+  if(WITH_PYTHON_MODULE)
+    add_definitions(-DWITH_PYTHON_MODULE)
+  endif()
+
   if(WITH_PYTHON_SAFETY)
     add_definitions(-DWITH_PYTHON_SAFETY)
   endif()