Maya: Transfer Mesh UVs After Rigging

This is slightly off-topic than the usual scripting posts, but I found this really useful and wanted to share.

It's a technique on how to transfer UVs from one mesh to another while maintaining deformer history on your object. It worked for what I was doing and I imagine I'll be using it again in the future.

http://animbiz.blogspot.com/2010/02/transferring-uvs-after-rigging.html

I'm currently working on a bullet proof transfer script, I'll let the world know when it works. :)

Maxscript: Check If Auto Key Is Turned On

Need to query if auto key is turned on or off using maxscript? Use the animButtonState command. It returns true or false, so using this info you can check it's current state and then setup a toggle for it, or use it make sure Max is in the correct mode before running a script.

Simple, yet extremely useful!

MEL To Maxscript To MEL

For whatever reason, I am a huge fan of using MEL to export a Maxscript file and vice versa. There is a strange feeling of satisfaction, something along the lines of getting away with a crime or not letting the man bring you down. Grab your code by the balls. That is all. :)

MEL/PyMEL: Get Top Most Parent Of An Object

Here is a function I use often that will give you the top-most parent of any object. I use it when I want to perform a function on an entire heirarchy but don't want to worry about needing to select the top most object. I can just grab any of them, hit a button and it grabs the top (using the function here) and then selects or grabs the entire hierarchy. I'm kind of OCD about saving every possible second.

Mel Version:

// **********************************************************
// Return Top Parent Of Any Node
global proc string jgReturnTopParent (string $obj) {

string $a[] = {} ;
string $b ;
$a = `listRelatives -p $obj` ;
while(size($a) > 0) {
    $b = $a[0] ;
    $a = `listRelatives -p $a[0]` ;
}
return $b ;

}

PyMel Version:

##################################################
## Return Top Parent Of Any Node
def jgReturnTopParent(obj):

 # Imports
 import pymel.core as pm

 # Get First Parent
 varA = pm.listRelatives(obj,p=True)

 # Loop All Parents
 while(len(varA) > 0):

    varB = varA[0]
    varA = pm.listRelatives(varA[0],p=True)

 return varB

Update: Thanks to Scott Englert for pointing out in the comments that MEL and PyMel both have built in functions for this already.

MEL command that comes with Maya:
rootOf($obj);

PyMEL method of dag nodes:
obj.root()

Cheers Scott!

Get Maya Version With MEL

Today I had to figure out how to get the current Maya version with MEL. I assumed it would be in some sort of environment variable but it turns out it had it's own command. I spent a good fifteen minutes trying to track this down so I hope this blog post can save somebody out there at least some of that time.

The command is getApplicationVersionAsFloat.

float $mayaVersion = `getApplicationVersionAsFloat` ;

Using White Space To Your Advantage

A really helpful hint when scripting is to know how to leverage white-space in your code. What this means is that certain languages will allow a lot of flexibility in the way your code is laid out that can make it much easier to read and edit. Take this example:

string $fileArray[] = {"C:/_Maya/temp/file_0001.ma","C:/_Maya/temp/file_0002.ma","C:/_Maya/temp/file_0003.ma","C:/_Maya/temp/file_0004.ma","C:/_Maya/temp/file_0005.ma","C:/_Maya/temp/file_0006.ma","C:/_Maya/temp/file_0007.ma","C:/_Maya/temp/file_0008.ma","C:/_Maya/temp/file_0009.ma","C:/_Maya/temp/file_0010.ma","C:/_Maya/temp/file_0011.ma","C:/_Maya/temp/file_0012.ma","C:/_Maya/temp/file_0013.ma","C:/_Maya/temp/file_0014.ma","C:/_Maya/temp/file_0015.ma","C:/_Maya/temp/file_0016.ma","C:/_Maya/temp/file_0017.ma","C:/_Maya/temp/file_0018.ma","C:/_Maya/temp/file_0019.ma","C:/_Maya/temp/file_0020.ma"} ;

The code above shows a string array containing twenty Maya Ascii files. It's straight forward, but a little difficult to read due to it all being condensed. If you need to make edits to one of the file names or add some into the list somewhere specific it can be a bit annoying finding the right spot. Let's use white space to help us with this.

string $fileArray[] = {
 "C:/_Maya/temp/file_0001.ma",
 "C:/_Maya/temp/file_0002.ma",
 "C:/_Maya/temp/file_0003.ma",
 "C:/_Maya/temp/file_0004.ma",
 "C:/_Maya/temp/file_0005.ma",
 "C:/_Maya/temp/file_0006.ma",
 "C:/_Maya/temp/file_0007.ma",
 "C:/_Maya/temp/file_0008.ma",
 "C:/_Maya/temp/file_0009.ma",
 "C:/_Maya/temp/file_0010.ma",
 "C:/_Maya/temp/file_0011.ma",
 "C:/_Maya/temp/file_0012.ma",
 "C:/_Maya/temp/file_0013.ma",
 "C:/_Maya/temp/file_0014.ma",
 "C:/_Maya/temp/file_0015.ma",
 "C:/_Maya/temp/file_0016.ma",
 "C:/_Maya/temp/file_0017.ma",
 "C:/_Maya/temp/file_0018.ma",
 "C:/_Maya/temp/file_0019.ma",
 "C:/_Maya/temp/file_0020.ma"
} ;

Cool huh? MEL and most languages will allow you to do this and many other things with white space in your code to really space it out evenly and neatly so it's easy for you and anyone else interacting with your scripts to use and read. Practice ways of using this trick to make your code more awesome!