Using FBX SDK (Python) - Namespace Removal Edition
It's not often mentioned, but this SDK is actually quite useful
目次
Update History
2020-09-23: Fixed an oversight in the code example
FBX is commonly used for exchanging digital assets in game development.
Typically, specialized software or DCC tools are used to edit its contents.
However, for simple tasks that don't require human intervention, creating a small tool can be more convenient than launching specialized software.
For example,
Installation
You can download it from Autodesk's website. There are several types available:
- FBX SDK Downloads: For creating C++ applications
- FBX Python SDK: For calling FBX functions from Python
- FBX Python Bindings: For writing and building applications in Python
There are also bindings for other languages available from sources other than Autodesk, but we won't cover those here (it's probably easier to just write in C++).
For this article, we'll use the middle option, FBX Python SDK, to create our tool.
After running the downloaded installer, it will be extracted to
C:\Program Files\Autodesk\FBX\FBX Python SDK\2020.0.1. In thelibfolder, you'll find modules for different Python versions. Add the appropriate one to yourPYTHONPATHbased on your Python environment.
Code
import FbxCommon
sdk_manager, fbx_scene = FbxCommon.InitializeSdkObjects()
result = FbxCommon.LoadScene(sdk_manager, fbx_scene, fbx_path)
This allows you to load the FBX file at fbx_path. After loading, you can retrieve and edit scene information from fbx_scene. For example, to get the root (transform):
root = fbx_scene.GetRootNode()
For our namespace removal task, we need to traverse all elements and rename them. We'll ignore potential name collisions for now. There's no convenient way to enumerate all nodes, so we need to pay attention to the types of nodes we want to modify and count them by type. Below is an implementation example. There are several possible specifications, so feel free to modify it according to your needs.
# -*- coding: utf-8 -*-
"""Utility script for fbx file, removing namespace from nodes.
Example
-------
$ python remove_namespace_recursively.py input_fbx_file_path output_file_path(optional)
Development Notes
-----------------
see http://help.autodesk.com/view/FBX/2020/ENU/?guid=FBX_Developer_Help_cpp_ref_index_html
"""
# ----------------------------------------------------------------------------
import sys
import argparse
import FbxCommon
from logging import ( # noqa:F401 pylint: disable=unused-import, wrong-import-order
StreamHandler,
getLogger,
WARN,
DEBUG,
INFO
)
if False: # pylint: disable=using-constant-test, wrong-import-order
# For type annotation
from typing import ( # NOQA: F401 pylint: disable=unused-import
Optional,
Dict,
List,
Tuple,
Pattern,
Callable,
Any,
Text,
Generator,
Union
)
from pathlib import Path # NOQA: F401, F811 pylint: disable=unused-import,reimported
from types import ModuleType # NOQA: F401 pylint: disable=unused-import
from six.moves import reload_module as reload # NOQA: F401 pylint: disable=unused-import
# ----------------------------------------------------------------------------
handler = StreamHandler()
logger = getLogger(__name__)
logger.setLevel(INFO)
logger.addHandler(handler)
logger.propagate = False
# ----------------------------------------------------------------------------
def remove_namespace_recursively(node, namespace):
# type: (FbxCommon.fbx.FbxNode, Text) -> None
"""Remove namespace from given node's name and its children recursively."""
for i in range(node.GetChildCount()):
kid = node.GetChild(i)
remove_namespace_recursively(kid, namespace)
new_name = node.GetName().replace("{}:".format(namespace), "")
node.SetName(new_name)
def remove_namespace(fbx_path, output_path):
# type: (Text, Text) -> None
"""Remove namespace root nodes of given fbx file and save to output_path"""
sdk_manager, fbx_scene = FbxCommon.InitializeSdkObjects()
logger.info("Load File: %s", fbx_path)
result = FbxCommon.LoadScene(sdk_manager, fbx_scene, fbx_path)
if not result:
logger.error("An error occurred while loading the scene...")
return
root = fbx_scene.GetRootNode()
ns = None
for i in range(root.GetChildCount()):
kid = root.GetChild(i)
ns = ":".join(kid.GetName().split(":")[0:-1])
_remove_namespace(fbx_scene, ns)
FbxCommon.SaveScene(sdk_manager, fbx_scene, output_path)
# Destroy all objects created by the FBX SDK.
sdk_manager.Destroy()
def _remove_namespace(scene, namespace=None):
# type: (FbxCommon.FbxScene, Text) -> None
def __get_new_name(name):
if False and namespace:
return name.replace("{}:".format(namespace), "")
else:
return name.split(":")[-1]
general_funcs = [
# [scene.GetGenericNodeCount, scene.GetGenericNode],
[scene.GetCharacterCount, scene.GetCharacter],
# [scene.GetControlSetPlugCount, scene.GetControlSetPlug],
[scene.GetCharacterPoseCount, scene.GetCharacterPose],
[scene.GetPoseCount, scene.GetPose],
[scene.GetNodeCount, scene.GetNode],
[scene.GetMaterialCount, scene.GetMaterial],
[scene.GetTextureCount, scene.GetTexture],
[scene.GetVideoCount, scene.GetVideo],
]
for countup, getter in general_funcs:
for i in range(countup()):
node = getter(i)
new_name = __get_new_name(node.GetName())
node.SetName(new_name)
for i in range(scene.GetGeometryCount()):
geo = scene.GetGeometry(i)
geo_funcs = [
[geo.GetShapeCount, geo.GetShape],
[geo.GetDeformerCount, geo.GetDeformer],
]
for countup, getter in geo_funcs:
for j in range(countup()):
try:
node = getter(j, 0)
new_name = __get_new_name(node.GetName())
node.SetName(new_name)
for k in range(node.GetBlendShapeChannelCount()):
channel = node.GetBlendShapeChannel(k)
print(channel.GetName())
new_name = __get_new_name(channel.GetName())
channel.SetName(new_name)
except Exception as e:
logger.error(e)
# pass
new_name = __get_new_name(geo.GetName())
geo.SetName(new_name)
def parse_args(args):
parser = argparse.ArgumentParser(description="Namespace remover for fbx")
parser.add_argument('fbx_path',
help='The input fbx file to be removed namespace.')
parser.add_argument('target_node',
help='The input fbx file to be removed namespace.')
parser.add_argument('output_path', nargs='?',
help='The output fbx file to saved.')
args = parser.parse_args(args)
if not args.output_path:
output_path = args.fbx_path
else:
output_path = args.output_path
return args.fbx_path, output_path
def main(*args):
"""Main entry point, parse args and execute the function."""
if 0 < len(args):
pass
elif 1 < len(sys.argv):
args = sys.argv[1:]
else:
logger.error("argument required")
fbx_path, output_path = parse_args(args)
remove_namespace(fbx_path, output_path)
if __name__ == "__main__":
main()
Other Uses
This article demonstrated namespace removal, but there are many other ways to utilize the SDK. For example, you can apply offsets to transforms in bulk, change unit systems, swap axes, modify hierarchies, and more.