feat(external_bpy): Setup temporary dir in init when in external mode

And signal handlers, so everything works the same when using blenderproc module
in standalone script.

blenderproc/command_line.py

@@ -2,7 +2,6 @@
 
 import argparse
 import os
-import shutil
 import signal
 import sys
 import subprocess
@@ -13,6 +12,7 @@
 # pylint: disable=wrong-import-position
 from blenderproc.python.utility.SetupUtility import SetupUtility, is_using_external_bpy_module
 from blenderproc.python.utility.InstallUtility import InstallUtility
+from blenderproc.python.utility.Utility import Utility
 # pylint: enable=wrong-import-position
 
 
@@ -141,12 +141,6 @@ def cli():
         # Setup temp dir
         temp_dir = SetupUtility.determine_temp_dir(args.temp_dir)
 
-        def clean_temp_dir():
-            # If temp dir should not be kept and temp dir still exists => remove it
-            if not args.keep_temp_dir and os.path.exists(temp_dir):
-                print("Cleaning temporary directory")
-                shutil.rmtree(temp_dir)
-
         # Setup env vars
         used_environment = dict(os.environ, PYTHONPATH=repo_root_directory, PYTHONNOUSERSITE="1")
         # this is done to enable the import of blenderproc inside the blender internal python environment
@@ -185,7 +179,7 @@ def clean_temp_dir():
                 finally:
                     assert script_directory in sys.path
                     sys.path.remove(script_directory)
-                    clean_temp_dir()
+                    Utility.clean_temp_dir()
         else:
             # Install blender, if not already done
             custom_blender_path, blender_install_path = InstallUtility.determine_blender_install_path(args)
@@ -213,7 +207,7 @@ def clean_temp_dir():
 
             # Listen for SIGTERM signal, so we can properly clean up and terminate the child process
             def handle_sigterm(_signum, _frame):
-                clean_temp_dir()
+                Utility.clean_temp_dir()
                 p.terminate()
 
             signal.signal(signal.SIGTERM, handle_sigterm)
@@ -228,7 +222,7 @@ def handle_sigterm(_signum, _frame):
                 p.wait()
 
             # Clean up
-            clean_temp_dir()
+            Utility.clean_temp_dir()
 
             sys.exit(p.returncode)
     # Import the required entry point

blenderproc/python/utility/Initializer.py

@@ -1,19 +1,25 @@
 """ This module provides functions to init a BlenderProc scene. """
 
+import atexit
 import os
 import random
+import signal
 
 from numpy import random as np_random
 import bpy
 
 from blenderproc.python.utility.GlobalStorage import GlobalStorage
-from blenderproc.python.utility.Utility import reset_keyframes
-from blenderproc.python.utility.SetupUtility import is_using_external_bpy_module
+from blenderproc.python.utility.Utility import Utility, reset_keyframes
+from blenderproc.python.utility.SetupUtility import SetupUtility, is_using_external_bpy_module
 from blenderproc.python.camera import CameraUtility
 from blenderproc.python.utility.DefaultConfig import DefaultConfig
 from blenderproc.python.renderer import RendererUtility
 
 
+def handle_sigterm(_signum, _frame):
+    Utility.clean_temp_dir()
+
+
 def init(clean_up_scene: bool = True):
     """ Initializes BlenderProc.
 
@@ -28,6 +34,14 @@ def init(clean_up_scene: bool = True):
         raise RuntimeError("BlenderProc has already been initialized via bproc.init(), this should not be done twice. "
                            "If you want to clean up the scene, use bproc.clean_up().")
 
+    if is_using_external_bpy_module():
+        # When in external mode we setup the temporary directory, and the cleanup handlers here, as
+        # this is the only mandatory initialization point and any of the code in command_line.py
+        # isn't executed. 
+        SetupUtility.setup_utility_paths(SetupUtility.determine_temp_dir(None))
+        atexit.register(Utility.clean_temp_dir)
+        signal.signal(signal.SIGTERM, handle_sigterm)
+
     if clean_up_scene:
         clean_up(clean_up_camera=True)
 

blenderproc/python/utility/Utility.py

@@ -2,6 +2,7 @@
 
 import os
 import csv
+import shutil
 import sys
 import threading
 from types import TracebackType
@@ -101,6 +102,13 @@ def get_temporary_directory() -> str:
         """
         return Utility.temp_dir
 
+    @staticmethod
+    def clean_temp_dir() -> None:
+        """ Removes the temporary directory if it exists. """
+        if os.path.exists(Utility.temp_dir):
+            print("Cleaning temporary directory")
+            shutil.rmtree(Utility.temp_dir)
+
     @staticmethod
     def merge_dicts(source: Dict[Any, Any], destination: Dict[Any, Any]) -> Dict[Any, Any]:
         """ Recursively copies all key value pairs from src to dest (Overwrites existing)