C++ and Python

You can access MotionBuilder’s API by running Python scripts or by creating compiled plugins in C++.

This programmer’s guide describes how to use both C++ and Python. The SDKs are very similar. Function signatures are the same in both languages, so do not hesitate to look at examples in one language even if you are focusing on the other.

The SDK includes a seperate class reference for each of C++ and Python.

Most MotionBuilder functionality is exposed via C++ libraries, and a large subset of that is exposed to Python. Native UI elements are also available and you can use them to create your own tools that integrate with the MotionBuilder user experience.

MotionBuilder functionality exposed to Python is a subset of that exposed to C++ via OpenReality, which is in turn a subset of the functionality available through the graphical user interface.

A Python script is a file, usually with the extension .py, containing Python commands. These can either be generic Python commands, such as file IO, or they can be commands which access the parts of the ORSDK which are exposed to Python through pyfbsdk.pyd.

C++ plugins are made by compiling code into Dynamically Linked Libraries (DLLs) which you put in the plugins directory.

C++ pros

Runs faster than Python.
More classes and functions are exposed via C++, and there are more callbacks.
C++ code can execute Python scripts, but Python cannot execute C++ plugins.

Python pros

Compared to many other programming languages, Python is easy to use and learn. Its design emphasizes programmer productivity and code readability.
Interactive interpreter: you can type lines of code and have them execute immediately. With C++ you must compile your code into DLLSs, put them in the plugins directory, and close and restart MotionBuilder to test it.
Python is a multi-paradigm language, meaning that you can write simple procedural scripts, but like C++, Python also supports object-oriented concepts such as polymorphism, inheritance, classes, and encapsulation.
Python is used as a scripting language for many tools including Autodesk Maya and Autodesk Softimage, as well as being widely used in pipelines throughout the computer graphics industry. The Python official web site at python.org includes documentation, downloads, and links to the community.
Python is free, but to use C++ you’ll need Microsoft Visual Studio.