Around the Corner

Maya 2025 API Update guide

The guide is based on What’s New in the Maya Devkit in Maya 2025 with some extra info. The details could be found [here in the document](https://help.autodesk.com/view/MAYADEV/2025/ENU/?guid=2025-Whats-New-in-API). ## Building environment In Maya 2025, the building environment changes on Mac. Operating System Requirements Windows Visual Studio 2022 (17.8.3 or higher) | macOS Xcode version 14.3 or higher | Linux RHEL or Rocky Linux 8.6 or higher, DTS-11 with gcc 11.2.1 | The minimum version of CMake required is 3.27.3. ## Migration... Read more →

Using Maya template for creating deformer UI

Recently, a customer asked a question about creating UI for deformers. The deformer nodes in Maya are created with a table for deformer attributes e.g., But for deformer plugins, if you don’t have an AETemplate assigned for it, it looks like this, which is not as easy to understand and has extra, but unnecessary details… The first thought is about reusing the AETemplates in scripts. Unfortunately, it wasn’t created with MEL and you can’t find it inside of scripts/AETemplates. AETemplate... Read more →

How to build PyQt5 for Maya 2024

Maya 2024 is shipped with Python 3.10 only on all platforms. Although pip is shipped with Maya 2024, we still can't use it to install PyQt5 on Mac or Linux. On windows, pip installed packages could work. However, it has its own Qt5 libraries installed and it may lead to problems. You may want to replace them with the ones shipped with Maya. I didn't encounter any problems during my testing with the original pip packages. If you find any... Read more →

Maya 2024 API Update guide

The guide is based on What’s New in the Maya Devkit in Maya 2024 with some extra info. For more details including commands and scripts changes, please checkout the documentation for more details. Building environments In Maya 2024, we made significent changes on the building environment. The minimum supported version of CMake has been updated to 3.22.1. Platform OS Building Environment Windows - Visual studio 2022, .NET 4.8.1 Linux RHEL 8.6+ DTS-11 + gcc 11.2.1 Mac - Xcode 13.4+, macOS... Read more →

How to build PyQt5 for Maya 2023

Maya 2023 is shipped with Python 3.9 only on all platforms. Although pip is shipped with Maya 2023, we still can’t use it to install PyQt5 on Mac. Unlike Maya 2023 on windows, pip installed packages could work. However, it has its own Qt5 libraries installed. You may want to replace them with the ones shipped with Maya. I didn’t encounter any problems during my testing with the original pip packages. If you find any problems with it, you can... Read more →

Maya 2023 API Update guide

The guide is based on What’s New in the Maya Devkit in Maya 2023 with some extra info. For more details including commands and scripts changes, please checkout the documentation for more details. Our Maya documentation team is also interested to know how impactful Developer documentation improvements have been over the past few releases. If you have a moment, please take this short survey to help us improve and know what is most important for you. Building environments The building... Read more →

How to build PyQt5 for Maya 2022

How to build and install PyQt5 for Maya 2022 Python 3. Read more →

How to build PyQt5 for Autodesk Maya 2020

Written by Cyrille Fauvel – Autodesk Developer Network (April 2013) Updated by Chengxi Li and Lanh Hong - Autodesk Developer Network (December 2019) Building SIP and PyQt for Maya 2020 is a python binding to the Qt library. Because Maya uses Qt internally, you can use the PyQt modules in Maya python scripts to create custom UI. PyQt does not have the same licensing as Maya, Qt, or Python. Please consult the PyQt website for information about licensing for PyQt... Read more →

How to build PyQt5 for Autodesk Maya 2018 64bit

Written by Cyrille Fauvel – Autodesk Developer Network (April 2013) Updated by Chengxi Li - Autodesk Developer Network (August 2018) Building SIP, and PyQt for Maya 2018 PyQt [https://www.riverbankcomputing.co.uk] is a python binding to the Qt library. Because Maya uses Qt internally, you can use the PyQt modules in Maya python scripts to create custom UI. PyQt does not have the same licensing as Maya, Qt, or Python. Please consult the PyQt website for information about licensing for PyQt. Download... Read more →

How to build Pillow on windows with Maya 2017/2018

Pillow is a Python image library with several other libraries built-in. Because it is originally built with VC2008, we can't use the wheel package with Maya. We'll need to build it manually. I wrote this blog for Maya 2017 at first. For Maya 2018, please use replace building environment with VS2015 and Windows SDK 8.1. Requirements VS2012 update 4 CMake > 3.3 Python 2.7.11 source code Windows SDK 7.1A Preparation Before we build Pillow, we need to install setup tools.... Read more →

Integrate p4 Version Control in Motionbuilder

Version Control is an important feature for a team to work together, and Motionbuilder has its own version control manager that uses simplified versions of the Perforce and Microsoft Visual SourceSafe version control software products. But, how to set it up? How to use the provided API to operate with version control? There are very few information about this, but recently, I spent some time on this, and in what follows I will talk about how to set it up... Read more →

How to import/export Render Setup with Python

Render setup is very useful for managing render layers and it can import and export render layers for later usage. However, the information on how to import/export it in Python is quite sparse. After doing some research on our testing code, I found that it is quite easy. There is renderSetup.decode and renderSetup.encode for import and export, respectively. The prototype for decode is decode(jsonObject, importOption, optionalPrefix), where - the jsonObject is the json string you'll need to import; - the... Read more →

All about modifying reference file in Motionbuilder

I believe most of you are familiar with File Reference System, it’s commonly used in different Autodesk products, including Motionbuilder. Recently, some partners are working with file reference in Motionbuilder, they have some confusion and also find some issues. I reviewed this feature on Mobu SDK help again, and I think it worth a post to mention some important point about modifying referenced file within Motionbuilder, we will start with some questions. First of all, there are following 2 terms... Read more →

Render Setup improvement in Maya 2017: Interactive Sequence Rendering

The last main improvement for Render Setup feature is actually a new feature to render a sequence directly from Maya’s UI without executing a batch render (including support for loading the sequence in the Renderview for review), thanks to engineering team’s contribution, here is the detail if you are interested: Introduction Rendering of image sequences in Maya has traditionally been an offline process for the end-user via command-line or the batch render feature in Maya. This can be limiting for... Read more →

Render Setup improvement in Maya 2017: Render Settings Changes

The 2nd main improvement is about changes to render settings window callbacks to support the new workspaces UI feature, as I mentioned before, this information is also provided by our engineering team. Let’s take a look at the improvement. Introduction One of the changes introduced in Maya 2017 is the new workspaces feature. This feature includes a change that presents some problems for the Render Settings. Maya now retains the state of windows that were open in previous sessions of... Read more →

Render Setup improvement in Maya 2017: Support for AOV setups per layer and inclusion of AOV setups in exported templates

As you know in Maya 2016 Extension 2 we introduced the replacement for Maya render layers called “Render Setup”, during that period we introduced this feature to several 3rd party renderers in person. For Maya 2017 we have been making improvements to this feature that will allow for improved support for 3rd party renderers, and other recent changes have the potential to impact 3rd party renderers as well, will talk about the 3 improvements in the following separate blogs, and... Read more →

The trap while working with API MFnSet::isMember()

While working with Maya, sometimes, we create a set to handle multiple elements as a whole. We can add DG nodes, DAG components or plugs to the set and MFnSet is used to operate with the set, but there is one trap with the API that you need to know. Most of time, the API works well, the issue only happens when checking for a given DAG node component by MFnSet::isMember(const MDagPath& path, const MObject& component, MStatus* st). Currently, if... Read more →

Building SIP, and PyQt for Maya 2016.5

This is an updated version for Maya 2016.5' PyQt build instructions. This is an updated version of the Maya 2016 build instructions for PyQt and PySide (here). The very good news is that with Maya 2014 & onward, there is no more need to build PySide as it is coming by default in Maya :) libxml, openSSL, OpenAL, python2.7, qt-4.8.5-64 / Maya 2014/2015, qt-4.8.6-64 / Maya 2016 and tbb are also coming by default in the Maya include and lib... Read more →

Setting up Maya Hardware 2.0 using MEl/Python

Changing the render setting in Maya is straight forward, you can change the Hardware renderer very easily using Maya Render settings Window as you could see in the below image. But, how do you achieve the same thing using script code? If you execute the following code, you will see that Maya renders using "Maya Software". mel.eval('render -x 600 -y 800 "Render_Cam"') or the same code as just MEL, Maya still renders using "Maya Software". In addition to the above... Read more →

How to rebuild PySide2 for Maya 2017

Maya 2017 is moving to QT 5.6.1 and PySide2. PySide2 is currently still in alpha stage, so it's not as stable as it could be. We will continue to update it in our service packages. However, if you want to upgrade yourself, you can download and build it easily. Maya 2017 is built with MSVC2012, so we cannot introduce other vc runtime in our build environment. So we will build QT 5.6.1 with MSVC2012 and the Python shipped with Maya.... Read more →

Avoid DG evaluation caused by maya.cmds when there are python custom nodes in the scene in parallel mode

I ran into an issue about Maya 2016 extension 2 hanging earlier this week. The customer has a custom locator node in their scene and Maya hangs when running code like below: import maya.cmds as cmds cmds.evaluationManager(mode="parallel") for i in range(10): cmds.currentTime(i) After spending some time for debugging, the issue was found. It turns out that when Maya is executing Python, it will acquire a Python lock for the interpreter. During the parallel evaluation of your scene caused by cmds.currentTime,... Read more →

The idle queue isn't 100% a queue

This week, I ran into a strange problem with a multi-threading Python case from a partner. def foo(): for i in range(10): print i # call from main thread foo() # call from separate thread import threading mythread = threading.Thread(target=foo) mythread.start() The output is quite strange: 0 1 2 3 4 5 6 7 8 9 9 8 7 6 5 4 3 2 1 0 The child thread's output order is reversed, how did that happen? After spending some... Read more →

How to delete the scriptJob if it is created with parent (-p) flag after specified QWidget is closed

After creating a Qt window with PySide.you may want to assign a scriptJob window to it and remove the job after the window is closed with -p flag. For example in the following code: import maya.cmds as cmds import maya.OpenMayaUI as omui import PySide.QtCore as QtCore import PySide.QtGui as QtGui from shiboken import wrapInstance mayaPtr = omui.MQtUtil.mainWindow() mayaWindow = wrapInstance(long(mayaPtr), QtGui.QWidget) scriptJobWindow = QtGui.QMainWindow(parent = mayaWindow) scriptJobWindow.setObjectName('scriptJobWindow') scriptJobWindow.setWindowTitle('scriptJobWindow') scriptJobWindow.show() def scriptJob(): print "scriptJob callback" jobNum = cmds.scriptJob(p="scriptJobWindow", e= ["SelectionChanged",scriptJob]) But... Read more →

Get image from M3dView::readColorBuffer in Viewport 2

Although the API is marked as obsolete, it is the easiest way to get a screenshot from Viewport in Maya and many plug-ins are still using it. But if you are trying to get a MImage from Viewport 2, you may have some problem with your previous Python code like this. import maya.OpenMaya as openmaya import maya.OpenMayaUI as openmayaUI view = openmayaUI.M3dView.active3dView() img = openmaya.MImage() view.readColorBuffer(img) This code will not work because in Viewport 2, the image is stored as... Read more →

Python Recursion Limit

While executing third party plugins or your own plugins which is written in python, have you ever faced the “maximum recursion depth exceeded” error? Python lacks the tail recursion optimizations common in functional languages like LISP. Let’s say, you want to add the specified node to the node array in FBX using recursive function, we can use the below approach to travel the whole scene. However, if your scene contains more than 1000 nodes, you will get the recursion limit... Read more →

Use python to update attributes in XGen

Last week, somebody asked me how to update attributes in XGen. I found that there isn’t many XGen Python API examples. Some of XGen’ source code is included in your Maya folder \plug-ins\XGen\scripts\xgenm. It is always a good idea to take a look there for reference. The XGen Python module is called xgenm. We’ll use the functions inside this package to update the XGen descriptors. If you read the document in our website, you can find xgenm.xgGlobal is mentioned. It... Read more →

Building SIP, and PyQt for Maya 2016

This is an updated version for Maya 2016' PyQt build instructions. This is an updated version of the Maya 2015 build instructions for PyQt and PySide (here). The very good news is that with Maya 2014 & 2015 & 2016, there is no more need to build PySide as it is coming by default in Maya :) libxml, openSSL, OpenAL, python2.7, qt-4.8.5-64 / Maya 2014/2015, qt-4.8.6-64 / Maya 2016 and tbb are also coming by default in the Maya include... Read more →

MNodeMessage::AttributeChangedCallback() not called on kAttributeRenamed

Consider the following Python example import maya.OpenMaya as OM import maya.cmds def test (msg, plug, otherplug, *clientData): if msg & maya.OpenMaya.MNodeMessage.kConnectionMade: print "connection made" if msg & maya.OpenMaya.MNodeMessage.kConnectionBroken: print "connection broken" if msg & maya.OpenMaya.MNodeMessage.kAttributeEval: print "attribute eval" if msg & maya.OpenMaya.MNodeMessage.kAttributeSet: print "attribute set" if msg & maya.OpenMaya.MNodeMessage.kAttributeLocked: print "attribute locked" if msg & maya.OpenMaya.MNodeMessage.kAttributeUnlocked: print "attribute unlocked" if msg & maya.OpenMaya.MNodeMessage.kAttributeAdded: print "attribute added" if msg & maya.OpenMaya.MNodeMessage.kAttributeRemoved: print "attribute removed" if msg & maya.OpenMaya.MNodeMessage.kAttributeRenamed: print "attribute renamed"... Read more →

Building pywin32 for MotionBuilder 2015

Recently a customer came to ask why pywin32 do not work on Maya or MotionBuilder. The answer is very simple, Maya and MotionBuilder are compiled the lastest compiler to get the best performances and the latest technology possible. Maya itself is partially compiler with the Intel C++ compiler and Visual Studio 2012 SP4, whereas MotionBuilder uses Visual Studio 2012 SP4 only. The issue is that pywin32 and many of the Python libraries still use an older compiler, like sometimes the... Read more →

Building SIP, and PyQt for Maya 2015

This is an updated version for Maya 2015' PyQt build instructions. This is an updated version of the Maya 2014 build instructions for PyQt and PySide (here). The very good news is that with Maya 2014 & 2015, there is no more need to build PySide as it is coming by default in Maya :) libxml, openSSL, OpenAL, python2.7, qt-4.8.5-64, and tbb are also coming by default in the Maya include and lib folder, so unless you have a very... Read more →

SIP fix released

SIP v4.15.5 now contains the fix and is available on Riverbank's site. No need to patch the source code anymore. http://www.riverbankcomputing.com/software/sip/download Read more →

Fix for "sip.wrapinstance on Maya main window causes a hard crash"

Few month back, I wrote instructions to build PyQT for Maya 2014, but couple of weeks later someone came with a problem in using SIP with Maya. The issue was that Maya is crashing when someone tries to get the Maya handle and bind it using sip. I.e.: import sip as _sip import PyQt4.QtCore as _QtCore import PyQt4.QtGui as _QtGui import maya.OpenMayaUI as _OpenMayaUI mainWindow = _sip.wrapinstance(long(_OpenMayaUI.MQtUtil.mainWindow()), _QtCore.QObject) Hopefully, a colleague of mine Yves Boudreault investigated the issue and found... Read more →

How to check for error for MDataHandle::child()?

First if you're using the MPlug version, it cannot fail but if you're using the MObject version and if it fails, it would return an empty MDataHandle. I.e. equivalent to: MDataHandle tmp ; and its type() method should return you kInvalid. Unfortunately, if the child attribute is also a compound attribute, type() would also return kInvalid. So what's up? in order to keep MDataHandle operations fast in Maya, minimal checking is performed, which for most methods means no checking at... Read more →

FBMenu stops working after an exception was raised

When code associated with a custom menu item raises an exception, the menu item can no longer be executed for that session of MotionBuilder. Steps: Load and execute the script below From the New Menu, select 'SubMenu 1' Observe in the Python window that an exception is displayed in the output From the New Menu, select 'SubMenu 1' Observe that nothing is output. from pyfbsdk import * def eventMenu(control, event): raise Exception('kill this menu item') menuMgr = FBMenuManager() menuMgr.InsertFirst(None, "New... Read more →

PySide/PyQt and Maya Undo not good friends

Calling Maya commands from PySide/PyQt using MEL and/or their Python wrappers will display strange messages on the Maya console during undo/redo operation, and oftenly creates concerns if this a bug, or something gets wrong. Not at all - that is a side effect of how the command is called by the different interpreters. Consider this Python PySide/PyQt UI script: import sys from PySide import QtCore, QtGui from maya import cmds, mel class FormExample(QtGui.QWidget): def __init__(self): super(FormExample, self).__init__() btn = QtGui.QPushButton('My... Read more →

ADN Maya API training material freely available

Back from vacation, ..., and a tons of emails to process :( But I can see a light that is coming to an end. If you tried to contact me and not yet received an answer, please ping me again. Anyway I am pleased to announce that after many years we decided to publish our API training material as we will continue to maintain it in future. The video recordings are already published here: for Maya, for 3ds Max, for... Read more →

New Maya C++/C#/Python plug-in Wizards

This topic was suggested by one of our ADN members who had problems to setup his Mac OSX environment for building a Maya plug-in on the Mac. I quickly replied by a post here to mention what compiler / environment to use on the Mac since the Maya 2014 documentation is wrong (it actually still reference the Maya 2013 compiler / environment whereas it changed for Maya 2014). More important, you should better not upgrade to Mountain Lion if you... Read more →

MotionBuilder Custom Property .Selected not exposed to Python

When using Python in MotionBuilder, you can select object in the scene using the Python .Selected property. When setting that property to True, you would put the object into the selection list. However, Custom Properties do not have their .Selected Python property exposed which makes in theory impossible to select them programmatically. Hopefully there is a workaround :) The workaround is to use the .SetFocus() method. When using that method with the parameter set to True, you will put the... Read more →

Support Soft Selection with custom MPxComponentShape

MPxComponentShape allows the implementation of new user-defined shapes using components, however all the UI related feature (such as selection/drawing) has to be implemented with another class MPxSurfaceShapeUI. In the MPxSurfaceShapeUI class, there are select() and draw() functions you need to implement for your custom shape. The Maya devkit has 2 examples that demonstrates how to use this class: apiMeshShape and apiSimpleShape. The apiSimpleShape shows to how to use MPxSurfaceShapeUI to work with MPxComponentShape to achieve component selection and drawing. But... Read more →

Using Global Interpreter Locks (GIL) when developing Python code in C++

Python uses a Global Interpreter Lock (GIL) to ensures that Python code in only executing in a single thread at a time. When you use the Python C API and/or expose C++ code to Python, you have to re-acquire the GIL each time you call in a C Python API. This is also true when writing Python extensions for Maya or when using the Python C API from a Maya plug-ins. You will need to add these calls in a... Read more →

Building SIP, and PyQt for Maya 2014

This is an updated version for Maya 2014' PyQt build instructions. This is an updated version of the Maya 2013 build instructions for PyQt and PySide (here). The very good news is that with Maya 2014, there is no more need to build PySide as it is coming by default in Maya :) libxml, openSSL, OpenAL, python2.7, qt-4.8.2-64, and tbb are also coming by default in the Maya include and lib folder, so unless you have a very specific need,... Read more →

Selection time in MotionBuilder isn't as fast as expected

If you are using MotionBuilder 2012 and above, you should use the functions FBBeginChangeAllModels() and FBEndChangeAllModels() to accelerate the selection time otherwise the selection might not be smooth like in the UI. Here is an example: import time from pyfbsdk import * FBBeginChangeAllModels() s_Time = time.clock() all_Grp = FBSystem().Scene.Groups for grp in all_Grp : for item in grp.Items : item.Selected = True e_Time = time.clock() FBEndChangeAllModels() print "Select","ProccesTime = %s"%(e_Time - s_Time),"OK" If now you try the same code without... Read more →

Possible Misuse of MScriptUtil in Maya

Many of Maya's C++ API methods require that one or more of their parameters be passed as pointers or references. Their return values, too, can be pointers or references. In Python parameters of class types are passed by reference but parameters of simple types, like integers and floats, are passed by value, making it impossible to call those API methods from Python as Maya the Python API was mainly generated automatically using Swig (let's call it Python 1.0). The MScriptUtil... Read more →

Overriding Python sys.excepthook doesn't work in Maya

If you override the Python sys.excepthook, it doesn't seem to get called on uncaught exceptions in Maya. This is because it is not possible to override sys.excepthook directly as Maya already does that internally. However, since Maya 2011, there is a solution which will allow you to add your own exception hook. To perform an action when an exception occurs without modifying Maya's default printing of exceptions, do the following: import maya.utils def myExceptCB(etype, value, tb, detail=2): # do something... Read more →

Importing Python scripts from a different path than predefined ones

This post applies to Maya, but MotionBuilder as well (or any Python based application). The other day I wanted to source a Python script into Maya and he took me few minutes to realize there was no easy/automatic way to do this in Maya other than loading the script into the Maya Script editor and run it unlike with MEL and the source command where you can give the full path name of the MEL script. Fine, but I wanted... Read more →

Can my custom node survive to delete

When you use MDagModifier to delete the last shape under a transform, the transform is automatically deleted as well. That is the normal Maya behavior. It helps to keep the scene clear of orphaned transforms and is consistent with MDagModifier::createNode(), which will automatically create a parent if none is specified when creating the node. However, you need to know that MDagModifier::reparentNode() would not delete empty parents when that happens. And the 'delete' command doesn't behave the same way since it... Read more →

Querying animation layers returns FBBox

This is more a bug report with its workaround than anything else. But this one seems serious enough for me to bring it here. On MotionBuilder 2012 -> 2013 (and on the current PR release), if you attempt to query an animation layer from the current take, an FBBox object will be returned. But on new scenes (yet to be saved), FBAnimationLayer objects will be returned for the two default animation layers. But for any new layer you add, only... Read more →

MotionBuilder code convention change

In the past, MotionBuilder classes may be prefixed with a 'H'. The SDK now will enforce not using this syntax, and you will need to change your code accordingly. To avoid too much work here is a tip on doing it in VisualStudio or Notepad++ using Regular Expression. In copy paste form: {^|:b|\(|,|<}H{FB:i*}{[&*\)>]*:b*} \1\2*\3 Read more →

C++ Qt custom widget to Python

While it is rather easy to create a composite widget using Python and/or a true custom widget using Python (see examples in PyQt distribution /examples/designer/plugins/widgets), it becomes very unintuitive when you use C++ :( For this post we will be using a true custom Widget and go step by step on what you need to do to get it working and exposed in Maya. For this we will be using a clock (with seconds) The first thing is to create... Read more →

No 64bit integer attribute in Maya? no way!

Ok, but where is it? If you take a look to the Maya API documentation you will find a lot of things about 64b support, but the only classes specific to 64b will be: the MUint64Array which is an array of MUint64 data type, the MFnUInt64ArrayData class which allows the creation and manipulation of the MUint64Array objects for use in the dependency graph when the MDataHandle::type() method returns kUInt64Array. The MFnUInt64ArrayData / MUint64Array / MUint64 classes are present in the... Read more →