Maya Station

How to prevent Maya writing a "requires" command for a plug-in

Do you wonder why error messages about some plug-in or other that Maya cannot find continue to appear when you load a scene? Do you wish you could force Maya to unload a plug-in when saving your scene so you can avoid having it load again with the scene file ?

The objective of this tutorial is help you understand why Maya might include a reference to a plug-in in a scene file, and how to prevent Maya from doing so.

To complete this tutorial, you will need Maya 2015 SP6 or Maya 2015 Ext1 & SP6 because this Service Pack release includes two new MEL commands : unknownPlugin and unknownNode; this tutorial demonstrates how to use both of them.

Mayatomr not available after uninstalling mental ray for Maya 2015 SP2 plug-in patch (windows-only)

If you uninstall the mental ray for Maya 2015 Service Pack 2 plug-in patch on Windows, and find that Mayatomr is no longer appearing in Maya, you can work around this issue by modifying the following file:

C:\Program Files\Common Files\Autodesk Shared\Modules\Maya\2015\mentalray.mod

And changing these lines from:

+ LOCALE:en_US mayatomr 3.12.1.12 <MENTALRAY_DIR>
+ LOCALE:zh_CN mayatomr 3.12.1.12 <MENTALRAY_DIR>
+ LOCALE:ja_JP mayatomr 3.12.1.12 <MENTALRAY_DIR>

to:

+ LOCALE:en_US mayatomr 3.12.1.12 C:\Program Files\Autodesk\mentalrayForMaya2015\
+ LOCALE:zh_CN mayatomr 3.12.1.12 C:\Program Files\Autodesk\mentalrayForMaya2015\
+ LOCALE:ja_JP mayatomr 3.12.1.12 C:\Program Files\Autodesk\mentalrayForMaya2015\

And re-starting Maya.

mental ray Legacy Materials in Maya 2014 missing swatches/shading groups

Some mental ray materials are now classified as “Legacy Materials” in Maya 2014. Unfortunately, there is an issue where these materials will not appear with swatches or shading groups. Here is a list of the materials affected:

mib_glossy_reflection
mib_glossy_refraction
builtin_bsdf_architectural
builtin_bsdf_architectural_comp
builtin_bsdf_ashikhmin
builtin_bsdf_carpaint
builtin_bsdf_lambert
builtin_bsdf_mirror
builtin_bsdf_phong
path_material
mib_illum_lambert
mib_illum_phong
mib_illum_blinn
mib_illum_cooktorr
mib_illum_ward
mib_illum_ward_deriv
path_material
transmat
dgs_material
dielectric_material

To work around this issue, download the attached “mentalrayCustomNodeClass.mel” file and copy it into mentalrayForMaya2014/scripts. This will revert the mental ray material classifications to their Maya 2013-state.

Download MentalrayCustomNodeClass

Cheers!
Nelson

Maya's dirmap command

Unfortunately, there will be times in which moving OS will cause the directory structure of the file to break. It is always recommended to set project before a file is loaded in Maya's UI. When command line rendering using the "-proj" should be a requriement. If setting these and files are still missing and Maya is not locating files relative to the project the dirmap command can save time and help remap and textures.

What is dirmap? dirmap is a Maya command that will tell maya to scan and change directory structures as the scene is loaded.. This command works in two steps. First we need to enable it so Maya knows that path remapping must be done. The second part is to give the from and to arguemnts so maya can spot the bad path and replace it with the new one.

How to use this within the UI

1. Launch Maya and setup the dirmap commands so that Maya changes the paths when loading the scene. After loading re-save file. The commands would look something like.

dirmap -en true;
dirmap -m "C:/Users/cruzn/Desktop/trainingContent_troubleshooting//sourceimages/" "C:/Users/cruzn/Desktop/trainingContent_troubleshooting/missing/";

The above tells Maya that on load of a scene check for these parameters. If any hit the old path than the new path would be set. we can use multiple lines to remap texutres in different directories

Using dirmap without UI

If you wish to avoid having to load the scene in the UI and want to go straight in to rendering than the second option will be to make a *.mel procedure like.

global proc dirMap()
{
dirmap -en true;
dirmap -m "C:/Users/cruzn/Desktop/trainingContent_troubleshooting//sourceimages/" "C:/Users/cruzn/Desktop/trainingContent_troubleshooting/missing/";
}

Much like the first option you will need to change the paths to match the current folders.

Save this file as a dirMap.mel in C:/Users/username/maya/2013-x64\scripts. All the rendering machines will need this.

When rendering you will need to use the -preRender flag with the command to launch the script we created. It is case sensitive so please make sure you use the "dirMap" exactly as described in this example.

So with the paths set in the script and saved we can now render.

"C:\Program Files\Autodesk\Maya2013\bin\Render.exe" -r mr -v 3 -preRender "dirMap" Z:\pathtest.mb

This will make the changes to the paths before render begins. I use verbosity 3 to capture warning such as missing textures.

Cheers!

Nelson

Around the Corner: a new M&E developer blog

There is a new blog in town!  Around the Corner, is a blog dedicated to
plug-in developers working with Maya, MotionBuilder, FBX and any other
technology that strikes our fancy at the moment of blogging.

This blog is authored by Cyrille Fauvel and me (Kristine Middlemiss, I am
sad to say I am departing this blog :()

To tell you a little about our selves we are 2/6’s of the Media & Entertainment worldwide team of API gurus providing technical services through the Autodesk Developer Network.

When either of us comes across some information on programming for Autodesk
technologies that we think you’ll be interested in, then you can expect it to
be posted here. That will be technical (how-to) solutions derived from
answering questions from ADN partners and from Autodesk forum users, sample
projects, white papers screencasts, conference presentation material, and other
information derived from our work. This blog is a vehicle to put lots of up to
date information in one place so you can easily find what you need to solve
your programming problems.

Enjoy!

Kristine

mental ray Satellite 2013 Windows not working on machines

We have had users report that mental ray satellite 2013 is not running on some Windows 7 machines.  Users have reported errors of failed connection to the satellite machine or even running the service will fail with errors.

This seems to be occurying on machines that have missing Microsoft Visual C++ 2008 Redistributable Package which contains needed libraries to run some of our prodcts correctly. 

We provide the installer (vc redist_x64.exe) with our discs and our downloads. The downloaded package generally extracts to "C:\Autodesk" directory. After doing the extraction browse to the Maya directory in "C:\Autodesk" you will find the 3rd Party installer in "\3rdParty\x64\VCRedist\2010SP1\vc redist_x64.exe"

After the package gets installed everything should be working.

More information about Microsoft's Visual C++ 2008 Redistributable Package can be found here.

I just wanted to thank our users for making us aware of this issue.

Cheers!

Nelson

 

Creating simple fog in Maya with mental ray

A very short video showing users how to create a simple fog effect with a spolight. Using the mental ray transmat and parti volume nodes are the building blocks needed to get you on your way to creating volumetric fog effect.

Hope you enjoy.

 

Virtual Memory: a performance issue often forgotten

Are you working with large scenes or with big textures? Are you experiencing software crashes?

Possible scenario: You are working on a computer with Windows 7 and 6GB of RAM. When you load the scene, the memory usage is somewhere around 5GB. If you try to start a batch-render process Maya may crash.

Final Gather fails to render when map rebuild is set to off

There is an issue issue in Maya 2012 hf2 when the Map Visualizer is enabled and final gather map is set to off.  

As a workaround we can force the legacy finalgather map containers to be used.  

1. In the command line run "select miDefaultOptions;"

2. The attribute editor will load some mental ray options.  Scroll down and expand the "String Options" category and click "Add New Item"

3. Scroll down to the bottom of the list to see the new empty options.  Enter the following.

Name: finalgather legacy
Value: True
type:Boolean

Afterwards you should be able to set your scene as you normally would and the maps should work with final gather rebuilt off when the map visualizer is enabled..

Thanks to Ash for his contribution.

Cheers!

 

Is there a maximum resolution for images rendered with mental ray for Maya ?

I've been looking into this recently, and a little research suggests that the size of the frame buffer is an important factor to consider when rendering a high resolution image using mental ray for Maya.

While there are no explicit limits for the resolution parameter, it's important to understand how mental ray caches its frame buffers.