MetahumanNewDNALib Invoke

1. Introduction

Epic’s official open-source library MetaHuman-DNA-Calibration only supports old versions of DNA files.

In UE versions later than 5.6, DNA files can only be loaded with the MetahumanForMaya plugin.

If we want to use DNA files in standalone Python scripts without Maya dependencies, we need to dig into this plugin.

2. Analysis

Brief review of the installation of MetahumanForMaya:

1. Download the plugin from MetahumanForMaya
2. Add MAYA_MODULE_PATH to your system environment variables with the value C:\Program Files\Autodesk\Maya2025\modules
3. Unzip the zip file provided in the downloaded plugin to the C:\Program Files\Autodesk\Maya2025\modules
4. Refer to official documentation for installing the plugin into Maya.

The core scripts lie in the folder: C:\Program Files\Autodesk\Maya2025\modules\MetaHumanForMaya\lib\PyDNA\9.4.7\platform-windows\.sanitizers-off\.json-0

Since I found that Maya 2025 uses Python 3.11.4, I copied the lib folder from C:\Program Files\Autodesk\Maya2025\modules\MetaHumanForMaya\lib\PyDNA\9.4.7\platform-windows\.sanitizers-off\.json-0\python-3.11 to a standalone folder for future development.

Directly import the DNA file with:

import os
import sys

ROOT = os.path.dirname(__file__)
LIB  = os.path.join(ROOT, "lib")

sys.path.insert(0, LIB)
os.add_dll_directory(LIB)

import dna

The test script throws the error:

E:\Code\python\PyQT\lib>python test.py
Traceback (most recent call last):
  File "E:\Code\python\PyQT\lib\test.py", line 10, in <module>
    import dna
  File "E:\Code\python\PyQT\lib\dna.py", line 35, in <module>
    import _py3dna9_4_7
ImportError: DLL load failed while importing _py3dna9_4_7: 找不到指定的模块。

This means the _py3dna9_4_7 needs DLL dependencies.

So I used the third-party too Dependencies to detect which DLL files are needed.

It is clear the _py3dna9_4_7.pyd uses dna9_4_7.dll, polyalloc1_3_18.dll,statuscode1_2_12.dll, trio4_0_21.dll. Then I copied all the files into the folder, and the import dna command worked fine.

The final structure of the DNA lib is shown below: