Presence Mental Ray nodes despite removed

The mental ray plugins are removed in the Maya but for some reasons, there are times in which unknown nodes - mib_amb_occlusion keeps getting loaded into the scene, resulting the rendering process in errors.

When I tried to open a new default Maya scene, I am not seeing the unknown nodes, and I would says that it pops out of nowhere.
Is there any ways that I can throughly run a check to see if the exisiting plugins have any associations with Mental Ray?

By the way, I have checked the plugin directories and I am seeing nothing that is relating to Mental Ray

If you have had mentalray loaded in a scene, Mentalray nodes get created, and mentalray attributes get added to some of your other Maya nodes. (Shaders I believe?). If Maya sees either of these, it will load mentalray, and this will pollute/infect any scene opened after that. The easiest way to get rid of this crap is to delete the Mentalray plugin, load the scene, then save it again. If Maya can’t load the plugin, it will clean up the extra crap.

EDIT: Also, if you are loading external references into your scene such as a separate rig file, make sure that doesn’t contain Mentalray nodes.

[QUOTE=btribble;24776]If you have had mentalray loaded in a scene, Mentalray nodes get created, and mentalray attributes get added to some of your other Maya nodes. (Shaders I believe?). If Maya sees either of these, it will load mentalray, and this will pollute/infect any scene opened after that. The easiest way to get rid of this crap is to delete the Mentalray plugin, load the scene, then save it again. If Maya can’t load the plugin, it will clean up the extra crap.

EDIT: Also, if you are loading external references into your scene such as a separate rig file, make sure that doesn’t contain Mentalray nodes.[/QUOTE]

Hi btribble, thanks for getting back to me.
I was wondering if it is possible for an .obj file to contains mental ray nodes? I am asking this because in this first.obj file I am importing, I realized it is the one that is causing my scene to load in the MR nodes. But as I tried in a new scene and export out using similar geos (with MR nodes in it) as a second.obj file, there isn’t any MR nodes at all…

Any ideas?

I usually rename the Mental Ray install directory, delete any MR related nodes, then save the scene as .ma file (when possible, because Maya is extremely anal retentive when it comes to ‘unknown’ nodes and .ma files), and then reload it.
There are some cases though where MR seems to nestle itself into some mesh MPxData, which often complicates things a lot more.

This export import without the plugin usually cleans up the scene somewhat, or at least prevents MR from auto loading when done right (and when the MR folder is renamed back of course.)

It’s a stupid stupid workaround for a problem that should not even exists, but what can you do.

[QUOTE=svenneve;24778]I usually rename the Mental Ray install directory, delete any MR related nodes, then save the scene as .ma file (when possible, because Maya is extremely anal retentive when it comes to ‘unknown’ nodes and .ma files), and then reload it.
There are some cases though where MR seems to nestle itself into some mesh MPxData, which often complicates things a lot more.

This export import without the plugin usually cleans up the scene somewhat, or at least prevents MR from auto loading when done right (and when the MR folder is renamed back of course.)

It’s a stupid stupid workaround for a problem that should not even exists, but what can you do.[/QUOTE]

Hi svenneve, I totally got what you mean. I did tried out any available methods that I can find on the web.
The funny thing when I finally found out, it is due to the obj file that I have imported in which ‘miracously’ contains MR nodes and I am totally unable to replicate it.

And the worse thing would be I am seeing that quite some of the obj files are exactly in the same state.

I don’t see how an .obj could cause MR to load, but stranger things have happened. I would think that saving the empty Maya scene before importing the .obj would show that it already has the MR nodes in it.

we have the same problem with Turtle and elasticIK. the problem gets bigger when you start referencing in stuff. so if you have 3 refs with turtle nodes, then your current scene will get infected. so you need to open all 3 refs, remove turtle, save, then open your original file and clean turtle. Its like a virus really.

@ TheMaxx. We’ve found that Turtle nodes are far more dangerous than MentalRay ones. We’ve had crashing and corrupted scenes because of them. We’ve basically given up removing MentalRay nodes, but have invested quite a bit of time making sure that all the Turtle crap is stripped out of our scenes.

[QUOTE=btribble;24783]@ TheMaxx. We’ve found that Turtle nodes are far more dangerous than MentalRay ones. We’ve had crashing and corrupted scenes because of them. We’ve basically given up removing MentalRay nodes, but have invested quite a bit of time making sure that all the Turtle crap is stripped out of our scenes.[/QUOTE]

Yeah we have also hit crashes, and have a pretty good shotgun to remove turtle nodes and shelf. One new guy started and within a week it had spread to a good chunk of our files, what a nightmare

I have managed to derive as to why the .obj files are loading/ having of mental ray nodes in them.
It would seems that when the object file is being exported, it is being done in Maya 2012 which was loaded with the MR plugin. And hence it generates 2 files - .obj and .mtl file

Hence, when I am using Maya 2014 to load in the said .obj file where Maya 2014 is not loaded with the MR plugin, it is unconciously loading the MR nodes because of the .mtl file which consists of the material reference that was made onto the object file. And hence the presence of such nodes even when the Maya version 2014 I have been using does not have the MR plugins

Now I am having a headache as to how I am going to remove the line in the .mtl across tons of object files

“Now I am having a headache as to how I am going to remove the line in the .mtl across tons of object files”

Visual Studio find/replace in files is my go to first stop. Notepad++ does regex across multiple lines if you need that. If those can’t do it I resort to our good friend open().