Around the Corner

World position and Object position in Shader Fragment

When you write a Shader Fragment, you should use the right naming conventions. For example if you check parameters like “mayaUvCoordSemantic” the name should be “uvCoord”, for “tangent” the name should be “mayaTangentIn”. Even if you check the “Object Space Position” the name and the semantic both should be “Pm”. Check the below example. " " Read more →

How to get correct camera within multiple panes

To get the current camera of the view pane, usually, we can use the API FBRenderer::CurrentCamera to get the camera. But when there are multiple view panes, the API does not work as you expected, it always return back the camera of the 1st view pane, this is a known issue of Motionbuilder. So how to get the correct camera for the specified view pane? There are 2 different situations. First, let’s take a look at this example, if you... Read more →

Drawing and Selection tips in VP2.0

We have 2 options to draw the icon/geometry in VP2.0. The first one is using MUIDrawManager object, and another one is MRenderOverride. If you are developing a plugin using Maya node, both MUiDrawManager and MrenderOverride objects are available at any point in the implementation. One issue is that if you are trying to draw the geometry/icon in a callback like postRenderMsgCallback(), VP2.0 would already have finished the drawing at that time, and the MUIDrawManager object won’t be available. In this... Read more →

How to build customized QT 5.6.1 for Maya 2017 on Windows

I've written an article about how to build PySide2 earlier. Some partners were asking about how to build QT 5.6.1 This is a guide for building QT 5.6.1 on windows. Prerequisite: Visual Studio 2012 Update 4 or Update 5 QT 5.6.1 Ruby 2.1.7(32 bits) Perl for OpenSSL JOM (recommended) Build Steps: 1. Download and unzip the tarball from the Autodesk open source distribution page Depending on how you extracted the tar file, you may need to remove the ending digits... Read more →

Make RenderTarget larger than 4k in Maya 2016 and 2016 Extension 2

There is a restriction for Maya 2016 that doesn't allow Maya to use more than 4k textures. As a result, the size of Viewport 2 MRenderTarget is limited to 4096x4096. We've opened a back door to remove this restriction and allow users to use the maximum texture size supported by their graphics card. This is now possible due to a new environment value introduced in Maya 2016 SP6 and 2016 Extension 2 + SP1. This variable is named: MAYA_VP2_USE_GPU_MAX_TARGET_SIZE, you... 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 →

Compiler versions for Maya 2017

This is an update on previous posts for older versions which can be found here: Maya 2016 Extension 2, Maya 2016,Maya 2015, Maya 2014, Maya 2008 to 2013. Basically, the build environment of Maya 2017 does not change, it’s same as Maya 2016 extension 2, and also almost same as Maya 2016. The main change for Maya 2017 is the version of Qt and PySide, the details are listed as follow and the updated ones are marked in red with... Read more →

Specifying a File path correctly in MEL/Python

Whenever you write a MEL script or a Python script that contains a file path, you should pay attention to whether it is a relative file path or an absolute file path. In case of POSIX, it is very clear that the path separator is always forward slash (/). In case of Windows, you have to be bit careful on file path separator. If you specify a path on Windows, you have either to use forward slash (/) or double... 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 →

Enable component selection for MPxSubsceneOverride of apiMeshShape sample

In Maya 2016 Extention 2, Autodesk has completed the native Viewport 2 implementation, and it is now the main viewport. There are many new APIs introduced and I've already posted a blog about Make MPxSurfaceShape selectable in Viewport 2 that was a different change in Maya 2016 Extension 2. Today, I am going to talk about another change for the MPxSubsceneOverride. MPxSubsceneOverride::getInstancedSelectionPath and MPxSubsceneOverride::getSelectionPath are very important for the native Viewport 2 selection, especially for the component selection. When selecting... Read more →

Maya 2017 devkit - Building Qt plug-ins instructions

For the Qt plug-ins, these are the recent changes made that are not reflected in the documentation but are important to know. Using the qmake executable and its qt.conf file from the devkit archive is recommended. The use of this qt.conf file uses MAYA_LOCATION and DEVKIT_LOCATION to locate the expected header/library files. Therefore, users must set both environment variables before building the samples. DEVKIT_LOCATION should point to the directory where the devkit include, mkspecs, cmake directories are located. After running... Read more →

New API changes for Maya 2017 & MotionBuilder 2017

A couple of months ago, we released Maya 2016 Extension 2 and some people have asked us about Maya 2017 & MotionBuilder 2017. Now, they are here! Maya 2017 & MotionBuilder 2017 have been announced on July 26, 2016, during SIGGRAPH event. As usual, I’d like to highlight some changes/improvements on the API side. Maya API Changes: There are many API improvements in Maya 2017, especially for the Rendering feature. For all the details about API changes/improvements between Maya 2016... Read more →

Tips for the “name” attribute of connect element in the Fragment graph

Today, we are going to look at a little bit inside of fragment graph's connect element. For the first two attributes, from and to are self-explanatory. Essentially this allows connecting from one fragment's output to another fragment's input. However, the “name” attribute is not well explained. The fragment graph is designed like the dependency graph in Maya. Connecting different nodes and having outputs after running through a series of fragments you'll get the result. But unlike the dependency graph, the... 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 →

Template/un-template script

A script can be created that will template or un-template the selected object to bind it to a key. Then, if the object is already templated, it will un-template it and vice versa. To do template/un-template, there is no need to write a big script. Maya provides a MEL command (toggle) to template and un-template the selected object using “-template” option. toggle -template; 1. If objects are already templated, then above MEL command will un-template them. 2. If Objects are... Read more →

MFn::kFluid and MFn::KFluidData attribute connection and limitation

We can create an attribute(typed attribute) using the following Maya C++ API MFnTypedAttribute has 2 overload methods for creating attribute. MObject create (const MString &fullName, const MString &briefName, const MTypeId &id, MObject defaultData=MObject::kNullObj, MStatus *ReturnStatus=NULL) MObject create (const MString &fullName, const MString &briefName, MFnData::Type type, MObject defaultData=MObject::kNullObj, MStatus *ReturnStatus=NULL) Here is the sample code MObject fluidType::outGrid; MStatus stat; MFnTypedAttribute tAttr; outGrid = tAttr.create("outGrid", "ogd", MFn::kFluid, MObject::kNullObj, NULL); if (outGrid.isNull()) cerr << "object is null" << endl; tAttr.setWritable(false); tAttr.setStorable(false); If we... 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 →

Maya 2016.5 Viewport 2.0 on OSX : How to handle the "Current drawing engine does not support legacy viewport" warning

In Maya 2016 Extension 2 (2016.5), you may have noticed that on Mac OS X, Maya would give the following warning message: "Current drawing engine does not support legacy viewport". Maya 2016.5 uses OpenGL API version 4.1( please see the image below). The “OpenGL Core Profile (strict)” is the default rendering engine on Mac OS X which supports OpenGL version 3.2 and above. So, it won’t support OpenGL 2.1 and below features. If you still want to use OpenGL 2.1... Read more →

OpenColorIO Library Issues

The OpenColorIO library is a third-party library from Sony Pictures and it is opensource code found here. Through the Maya 2016 Extension 1 release, OpenColorIO library is included with the Maya release. The Maya customized OpenColorIO library is statically linked with the SynColor library (ie. SynColor.dll on Windows). Note that the OpenColorIO library supports all platforms as OpenColorIO.dll in Windows, OpenColorIO.so in Linux and OpenColorIO.dylib in OSX. If you download and build OpenColorIO on your own and then link with... Read more →

Compiler versions for Maya 2016 Extension 2

This is an update on previous posts for older versions which can be found here: Maya 2016, Maya 2015, Maya 2014, Maya 2008 to 2013. Basically, the build environment of Maya 2016 extension 2 is very similar as Maya 2016 with just a few updates, I listed them as follow and marked the updated and new added items in red with links to help you find it quickly. Maya 2016 Extension 2 Windows 64bit Win7x64 Visual Studio 2012 Update 4... Read more →

How to remove the white outline in the RenderView

The MRenderView::updatePixels API has an annoying side-effect of showing a white outline. For example, calling it in the default way on a rectangle will show it like this: There is an undocumented API available that can alleviate this problem. You can call the MRenderView::setDrawTileBoundary(false) method after startRender and it will disable Maya from drawing the outline. Unfortunately, this API is currently marked for deprecation. But we have discussed this with our engineering team, and they agree it is an acceptable... Read more →

Make MPxSurfaceShape selectable in Viewport 2 - Non-highlighted Maya 2016 Extension 2 API Changes

In Maya 2016, several APIs were introduced but marked as Not implemented or not mandatory. Some of them are now fully implemented in Maya 2016 Extension 2, and actually now required in your plug-in code. The Completion of native Viewport 2.0 selection feature is one of them. If you wonder why Maya 2016 had some ‘Not implemented’ API but signature present, it was to help binary compatibility between Maya 2016 versions of the plug-ins using these API. However, as you... Read more →

Maya 2016 Extension 2 installation issues - License(CLIC) and environment variables

If you have facing the issue below (CLIC Version Mismatch) after installing Maya 2016 Extension 2, it might be caused by having installed a previous version of an Autodesk beta software like Maya Preview Releases, and you did not uninstall it before prior installing the retail version. CLIC Version Mismatch To solve the problem, make sure to uninstall the Autodesk License Service on your computer, and next install the license service shipped with the Maya 2016 Extension 2. You can... 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 →

Maya and the Forge APIs - Discount for Forge DevCon

To start, have you heard about the new Autodesk Forge platform? Forge is a place that gathers many new cloud service APIs into one place for consumption by developers. Forge includes the platform technology, a program for supporting partners (think ADN open on a broader scale), including a developer conference coming in June, and a fund where startups can apply for an investment by the Forge fund. What does this have to do with Maya programming concepts? Well, there are... Read more →

New API changes coming in Maya 2016 Extension 2

Again, we come to another release season, but this year things are a little different. Maya 2017 is not released as usual. Instead, we are releasing Maya 2016 Extension 2, which is also being called Maya 2016.5. Some people may ask, where is my Maya 2017? Well, Maya 2017 may come later this year. Does it mean there are not many improvements of Maya at this point? The answer is absolutely “No”! Maya 2016 extension 2 includes many updates for... 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 →

XGenRenderAPI: How to use?

Maya is using procedurals for rendering translators. One of the reason of using procedurals is because the translators of some renderers are not extensible. For example, to keep modules independent, Mentalray’s Mayatomr.mll and XGen’s libAdskXGen.dll are not linked together. This means that the code using XGenRenderAPI doesn’t require a procedural. If third party renderer doesn’t support procedural, you can directly use XGenRenderAPI in the translator. To do this, you can call XGenRenderAPI::PatchRenderer::init() to initialize XGen primitive generation, and call FaceRenderer::render()... Read more →

Maya to be included in One LISP campaign

We are moving towards the cloud nowadays. I've heard some news from 3ds Max guys and they are going to add JavaScript support in the near future. It is wonderful for cloud products like A360 Cloud rendering services in 3ds Max. For the desktop products, we have some a similar movement in Maya. There are lots of programming languages for Autodesk developers today, like MAXScript, MEL, JavaScript, Python, C++, etc. But above all, AutoLISP should be most important, it is... Read more →

Create shader fragments as input for stock shader and other shaders

The shader fragment feature was introduced into Maya a few years ago and it is very useful for creating and extending shader features of Maya. Shader fragments can be used for creating input or output for existing hardware shaders. I am going explain how it works with two samples in our devkit. The first sample is VP2BlinnShader and it uses blinn stock shader as hardware shader. Another sample is fileTexture and it uses shader fragment to implement a fileTexture node.... 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 →

What should I do when elementByPhysicalIndex failed?

The other day, I encountered a problem when I tried to write a sample for Maya 2016. When I was trying to get an element in an array using a physical index, it worked fine most of the time. But it failed, when I was trying to get the elements inside a CV array. This time it returned an incorrect number of elements and thrown an error when I was accessing the array. It turned out that physical index is... Read more →

Autodesk Memento now available for Mac

My favourite mesh generation and manipulation tool, Autodesk Memento, is now available (in Beta) for the Mac. I’ve been part of the Alpha programme for the OS X version for some time: admittedly not very actively, but I did install a number of builds and report an error or two. I’m very happy to see the Mac version is now joining its Windows sibling in Beta. Both versions can be downloaded and installed from this page. The model shown at... Read more →

How to make your plugin node as thread-safe for parallel DG Evaluation

Take this example: Let’s take very simple DG setup. A locator whose transform is connected to two compute nodes (spliceMayaNode1 and spliceMayaNode2), each of which computes something heavy. The results are then added together in a third node (spliceMayaNode3) from the plugin, and that result drives a locator. The nodes use dynamic attributes so you have to use setDependentsDirty() to declare the outputs that are affected by which inputs. If you comment out the code that adds plugs to the... Read more →

Day on Intel buzz workshop

On October 28. Zhong and I attended a game workshop hosted by Intel in Shanghai. The show is mainly for the indie gaming developers and Html5. First, Intel demonstrated their XDK, which is pretty impressive for cross-platform Html5 development. It is based on Apache Cordova and has an optimized game browser: crosswalk. The improvement of crosswalk is significant, its performance is closing to the native games. Using Html5 to develop mobile games or apps becomes promising. Later, Cocos studio presented... Read more →

How to connect Perception Neuron with Maya (Part 2)

In the last post, I talked about the NeuronDataReader SDK and the general process to use these APIs, now we will talk about how to make a Maya plug-in client to receive and parse the animation data. With this project, we are going to create a Maya plug-in which will: fetch the animation data from Axis Neuron application to Maya, create a Neuron specific skeleton, and assign the animation data to the skeleton, retarget the animation from the skeleton to... Read more →

How to connect Perception Neuron with Maya (Part 1)

Last year, our team backed project Perception Neuron with 2 full set of Neuron Motion capture devices, and with some delay and some manufacturing issue, finally, around the end of last month, I received the devices. It was just around my birthday, so I consider them to be my birthday gift ;) The device looks well manufactured, well packaged, with simple but enough information about how to start playing with it. The Quickstart Guide at https://neuronmocap.com/quickstart is well written to... Read more →

Writing a Mental Ray shader for Maya and relate it to a Maya custom node

Mental Ray is the renderer shipped with Maya by default. To make your custom node working with Mental Ray becomes a natural question for every Maya developer. The Mental Ray renderer can use the Maya shader network, but because it is a different rendering system (provided by NVIDIA), it cannot use the shader node in Maya directly. For this reason, Autodesk has developed a shader bridge between Mental Ray and Maya. You can develop a Mental Ray shader easily and... Read more →

Maya 2016, Parallel Evaluation and New API’s

When you start Maya 2016, you will automatically be in parallel evaluation mode. This is new default evaluation mode, replacing the legacy DG-based evaluation. Maya 2016 uses the DG’s dirty propagation mechanism to build the Evaluation Graph(EG). Dirty propagation is the process of walking through the DG, from animation curves to renderable objects, and marking attributes on DG nodes as needing to be re-evaluated (i.e., dirty). Unlike previous version of Maya that propagated dirty on every frame, Maya 2016 disables... Read more →

Getting null from the MShaderManager::getShaderFromNode() in Maya 2015

Getting null from the MShaderManager::getShaderFromNode() in Maya 2015? Here comes one explanation. To make a surface shader work in VP2, Maya has to sync the surface shader with its connected shape. It happens automatically with build-in shapes, but for custom meshes defined in a plugin, you need to get the shader through MShaderManager::getShaderFromNode() and set it with MRenderItem::setShader(). It becomes tricky in Maya 2015 since the MShaderManager cannot do this for you automatically and you will get nothing from MShaderManager::getShaderFromNode().Therefore,... Read more →

Registering a plug-in to work with Maya archive

To add external dependencies to the archive created by Maya with "File" --> "Archive Scene", a plug-in developer needs to implement the MPxNode::getFilesToArchive() method. The documentation is [here](http://help.autodesk.com/view/MAYAUL/2016/ENU/?guid=__cpp_ref_class_m_px_node_html). This will add the plug-in node's external dependencies to the archive. While you are at it, you can add any file paths to Maya’s File Path Editor UI using this command: filePathEditor –registerType "myNode1.filePath" –typeLabel "Custom" If you wish to add the external dependencies to metadata in the Maya file itself, use... Read more →

Don't perform heavy tasks in the MoBu Real-time engine thread, even if it worked before

Recently we received a question about crashing while calling FBPlayerControl::GotoStart() from within a real-time device engine thread. It seems working fine up to MoBu 2014, but crashes in MoBu 2015. Actually, it seems working fine in previous MoBu releases, but as the best practice, it’s not recommended because the SDK documentation clearly mentions that some methods like DeviceIONotify() and DeviceEvaluationNotify() are called by the Real-time engine thread, and they should consume as little CPU time as possible and return as... 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 →

Some tips about the life cycle of Maya thread pool

Maya provides a class named MThreadPool to help developers to create or reuse a thread pool, if you want to know more about this, you can check out the online SDK here. If you want to know how to use MThreadPool, besides the above link, you can check out our 2 samples, threadTestCmd and threadTestWithLocksCmd in the Maya devkit. In the 2 samples mentioned above, you will see that MThreadPool is actually released twice by using MThreadPool::release(). The big question... Read more →

Autodesk University Call for Proposals

The Autodesk University Call for Proposals will close on May 26th, so there's still time to submit a proposal and get free entry to AU. My colleague, Stephen Preston, being the track lead for the 'Developer' track, is particularly interested in persuading you to submit a proposal for a class or lab on an API/programming topic. Your proposal could be on an Autodesk API, but we also like to include a few classes/labs each year on general programming topics (programming... Read more →

Advantage and limitation of using MUiDrawManager in VP 2.0

VP 2.0 provides a very convenient way for plugin developers to draw some simple basic UI elements such as lines, circles, arcs, text, …. In Maya 2016, it now provides the ability to support drawing icons. By using MUiDrawManager, plugin developers do not need to consider the different GPU device, it will work for all. MUiDrawManager is very powerful, some developers mention that they are trying to use that as much as possible. Actually, we provide several interfaces for partners... Read more →

New Api changes for Maya 2016 & MotionBuilder 2016

I just came back from Montreal for our team meeting there, this is my 1st time to be there, very nice city. It’s a great opportunity to meet with my team members again who are located in different countries, and I also met many engineers in the Maya, FBX and 3ds Max team. It has been really exciting. The new release of Maya 2016 version was announced on 16th April and everything is open to public now. I cannot wait... Read more →

Fedora Core 20 gcc 4.8.2 Installation instructions

If you are trying to build and install gcc 4.8.2 from source code on Fedora Core 20 box, you will find lot of challenges to fix the dependencies. To fix that issue and to reduce the time here I have listed out the steps to be followed to get the successful build. Install build pre-requisites: Before installing gcc 4.8.2, install the build pre-requisites 1. yum groupinstall "Development tools" 2. yum install glibc-devel.i686 glibc-i686 3. yum install gcc-c++ 4. yum install... Read more →

Maya compiler versions (update)

This is an update on previous posts for older versions which can be found here: Maya 2015, Maya 2014, Maya 2008 to 2013. Maya 2016 Windows 64bit Win7x64 Visual Studio 2012 Update 4 + Win 8 SDK .Net framework 4.5.1 Intel Composer XE 2015 Initial release (15.0.0.108) Linux 64bit RHEL/CentOS 6.5, FC20 gcc 4.8.2 Intel Composer XE 2015 Update 1 (15.0.1.133) Note: For our internal builds on RHEL/CentOS 6.5, we use Red Hat DTS 2.1 to have gcc 4.8.2, plug-in... Read more →