This section describes how to use the 3ds Max MaxPlus Python API.

The 3ds Max MaxPlus Python API is built on top of and based on the 3ds Max C++ SDK. Global functions, and functions from static interfaces such as the Interface class and the derived classes (Interface7 and so forth), have been regrouped into smaller classes based on functionality, such as: RenderSettings, Animation, Grid, or Snaps. Refactoring was performed for several functionalities in global functions, as well as the core interfaces into the INode class. The goal was to create an API that is more intuitive.

Use help and dir

help() and dir() are two of the most useful functions in Python.

For example, you can obtain a list of attributes for a class (list of methods, variables) using help as follows:

import MaxPlus
help(MaxPlus.Asset)

In your MAXScript Listener window, you will obtain a list of all attributes for the Asset class. To obtain a list of attributes for an object, you can also use the Python built-in dir() function. The dir(object) function, when passed an argument (object), returns a list of attributes for the object.

For more information regarding these two functions, as well as other tips and tricks, see MaxPlus Tips and tricks.

Printing in your script

In the 3ds Max environment, data sent from a Python script to sys.stdout (for example, by using print) or to sys.stderr is redirected to the MAXScript Listener window.

Note that 3ds Max is not thread-safe, so printing to the Listener Window from threads other than the main thread can cause the application to crash, and is not recommended. If you are using multiple threads in your script, you can disconnect sys.stdout and sys.stderr from the Listener using these commands at the beginning of your script:

sys.stdout = _old_stdout
sys.stderr = _old_stderr

About properties

A property is an attribute that is the equivalent of a Get() and Set()method pair. You can simply access the attribute to query or set its value.

There exist also read-only properties, which are the equivalent of their corresponding Get() methods.

For example, the ParameterBlock.GetName() method has a corresponding ParameterBlock.Name property.

In the demoApplyMaterial.py example:

m = MaxPlus.Factory.CreateDefaultStdMat()
m.Ambient = color
m.Diffuse = color

is equivalent to:

m = MaxPlus.Factory.CreateDefaultStdMat()
m.SetAmbient(color)
m.SetDiffuse(color)

In the Python API Reference documentation, there are attribute descriptions along the lines of:

tuple Type = _swig_property(GetType)

In this case, Type is a property that you can query to obtain the Type value, and its corresponding method is GetType().

Constants

Constants are represented in the Python API along the lines of ColorSelection = _MaxPlus.Colors_ColorSelection as a result of swig.