move library code into manimlib, replace relative imports with absolute imports

manimlib/utils/output_directory_getters.py

@@ -0,0 +1,42 @@
+import inspect
+import os
+
+from manimlib.constants import THIS_DIR
+from manimlib.constants import VIDEO_DIR
+
+
+def add_extension_if_not_present(file_name, extension):
+    # This could conceivably be smarter about handling existing differing extensions
+    if(file_name[-len(extension):] != extension):
+        return file_name + extension
+    else:
+        return file_name
+
+
+def guarantee_existance(path):
+    if not os.path.exists(path):
+        os.makedirs(path)
+    return path
+
+
+def get_scene_output_directory(scene_class):
+    file_path = os.path.abspath(inspect.getfile(scene_class))
+
+    file_path = os.path.relpath(file_path, THIS_DIR)
+    file_path = file_path.replace(".pyc", "")
+    file_path = file_path.replace(".py", "")
+    return guarantee_existance(os.path.join(VIDEO_DIR, file_path))
+
+
+def get_movie_output_directory(scene_class, camera_config, frame_duration):
+    directory = get_scene_output_directory(scene_class)
+    sub_dir = "%dp%d" % (
+        camera_config["pixel_height"],
+        int(1.0 / frame_duration)
+    )
+    return guarantee_existance(os.path.join(directory, sub_dir))
+
+
+def get_image_output_directory(scene_class, sub_dir="images"):
+    directory = get_scene_output_directory(scene_class)
+    return guarantee_existance(os.path.join(directory, sub_dir))