mel wiki

UploadLog

Tue, 13 May 2008 17:54:29 GMT

date	user	location	storeUrl	uploadDir	toFilename	backupdir	origin
11/4/2008 15:38:20	WarpCat	/	store.cgi	.	index.html	.
14/4/2008 10:9:13	WarpCat	/	store.cgi	.	index.html	.
15/4/2008 15:46:42	WarpCat	/	store.cgi	.	index.html	.
15/4/2008 16:30:53	WarpCat	/	store.cgi	.	index.html	.	Ok
15/4/2008 16:36:34	WarpCat	/	store.cgi	.	index.html	.
16/4/2008 13:52:59	WarpCat	/	store.cgi	.	index.html	.	Ok
16/4/2008 13:56:11	WarpCat	/	store.cgi	.	index.html	.
21/4/2008 10:54:13	WarpCat	/	store.cgi	.	index.html	.	Ok
21/4/2008 10:59:40	WarpCat	/	store.cgi	.	index.html	.
24/4/2008 9:2:38	WarpCat	/	store.cgi	.	index.html	.
24/4/2008 13:49:10	WarpCat	/	store.cgi	.	index.html	.
28/4/2008 15:47:26	WarpCat	/	store.cgi	.	index.html	.
29/4/2008 10:12:43	WarpCat	/	store.cgi	.	index.html	.
29/4/2008 13:45:49	WarpCat	/	store.cgi	.	index.html	.
5/5/2008 14:16:28	WarpCat	/	store.cgi	.	index.html	.
13/5/2008 10:53:54	WarpCat	/	store.cgi	.	index.html	.	Ok
13/5/2008 10:54:29	WarpCat	/	store.cgi	.	index.html	.

How do I change the selection from a polygon surface to all of its components?

Tue, 13 May 2008 17:52:36 GMT

polyListComponentConversion

Example, convert from selected faces to vertices:

select ‘polyListComponentConversion -tv‘;

polySelectConstraint

Example, convert a surface to all of it's faces:

polySelectConstraint -m 3 -t 0008;

You can also use this command to pick the shell elements of a surface, which can be really handy.

How can I query the 'painted weight' values on a Blend Shape?

Mon, 05 May 2008 21:13:00 GMT

Via the 'Deform-> Paint Blend Shape Weights Tool', you can paint the influence that a blend shape has on a mesh. The tool lets you save the weights out as a map, and read the weights back in. But where do the weights actually get stored on the object?

On the blendShape node's '.inputTarget.inputTargetGroup.targetWeight' att:

getAttr blendShape1.it[0].itg[0].tw;
// Result: 1 1 1 1  1 1 1 0.5 0.5 0.50.5 0.5 etc....

There is a 1:1 relationship beween these values, and the verts on the mesh.

I figured this out by looking in the .ma file itself. I couldn't find anything in Maya that would explain what\where these values were. You could edit them in the Component Editor, but it wouldn't explain what it was doing. And when you paint the actual weights, or load a weight file, neither does it tell you what it's doing then either.

I gave this info to someone else, and they came back with this description:

inputTarget[0]. >> Maybe your source mesh?
inputTargetGroup[1]. >> your target by index
targetWeights[0] >> the actual vert index to modify
0; > the value to set

Can I use a joystick in Maya? Sure!

Tue, 29 Apr 2008 20:45:00 GMT

This tool has actually been around for some time, and while I've never used it, my friends have and vouched for it's abilities:

JoystickServer by Jorge Imperial
Download from Highend3d.com here
It basically turns your joystick into a mocap device, which Maya can then interface with.

How do I turn the mouse into a mocap device?

Tue, 29 Apr 2008 20:45:00 GMT

recordAttr

Example:
Select the object you want to record motion on.
In the script editor, enter

recordAttr -at "translateX" -at "translateY"; // to control the tx and ty for example

Execute that bit of code. You'll see new "record1" outputs on your object
Next type in the script editor, but don't execute yet:

play -record;

Now:

select your object in the camera view,
go back and highlight 'play -record' in the script editor,
move your mouse back over your object (but do not pick it!),
and hit the 'Enter' button on the NUMBER pad.
This will execute the mel code, but leave your mouse right over your object ready to be selected and moved.

This will start the recorder, capturing your mouse movement.Click on the object, and start moving it.Obviously, you should constrain you translation plane to the two axes you've selected before you start this process.Hit Esc when done.
This can work for any attr you want actually, I just used trans as an example.
Also, if you want to delete the motion and try again, you'll need to also delete the "record" nodes that are output connections to your animated node as well. You can use this code:

delete `ls -type record`;

How do I export/import an "animFile" file using the command line with arugments?

Tue, 29 Apr 2008 17:12:00 GMT

Export an anim (with one or more objects selected):

file -es 
    -type "animExport" 
    -op "-cb api -fea 1 -animation objects -option keys -hierarchy none -controlPoints 0 -shape 000" 
    "c:/temp/foo.anim";

Import an anim (with one or more objects selected):

file -i 
    -type "animImport" 
    -op "targetTime=4; copies=1; option=replaceCompletely; connect=0;"
    "C:/temp/test.anim";

Notes:

You must have the "animImportExport?.mll" plugin loaded.
The options listed are based primarily on the copyKey and pasteKey mel commands. In the case of an export, the animation data is copied (via copyKey) into the api clipboard, and then sourced by the plugin for export. In the case of an import, the plugin copys the data from the anim file to the api clipboard, then pastes it (via pasteKey) onto the objects.

How can I query smooth skin weights on vertex:

Mon, 28 Apr 2008 22:47:00 GMT

Pick a vertex, and run:

// get just the object name from selection:
string $selObj[] = `ls -o -sl`;
// get the vert name
string $selPt[] = `ls -sl`;

// find our skindCluster:
string $sc[] = `listConnections -s 1 -d 0 -type "skinCluster" $selObj[0]`;

// get transforms (binding joints and influence object)
string $skinInfluences[]=`skinPercent -q -t $sc[0] $selPt[0]`;
// get skin weight of selected vertex
float $sknVals[]=`skinPercent -q -v $sc[0] $selPt[0]`;

// only print values that are greater than 0.  If you want to know 
// influence names even if they are zero, remove the 'if' line:
for($i=0;$i<size($skinInfluences);$i++)
    {
    if($sknVals[$i] > 0)  // print $sknVals[$i]
        print ($skinTrans[$i] + "\t\t" + $sknVals[$i] + "\n");
    }

the index of $skinTrans and $skinVals is 1-1 matched

How can I easily hold or unhold all the influence weights on skinned geo?

Thu, 24 Apr 2008 20:49:00 GMT

One of the most important things when painting smooth skin weights, is holding and unholding influence weights. If an influence is 'unheld' (unlocked), its influence weights can be modified. If it is held (locked), its influence weights can't be modified. In general when painting weights, you want ALL the influences held except the current two you're working on.

In the 'Paint Skin Weights Tool', under the 'Influence' frame, it shows the influence list for everything effecting that geo, and a button at the bottom to 'Toggle Hold Weights on Selected'. If you have 100 joints, then you need to pick each one in the list, and hit that button. This can be, really time consuming. What if you want to simply hold all the weights at once, then unhold just the two of your choosing?

Two simple shelf buttons can be written to do this, the code is below. The key is to query all the nodes in the scene with a .liw attr. .liw stands for "Lock Influence Weights", and any node that is added as a smooth skin influence will have this attr added to it. If the value is 1, the weights are locked\held. If the value is 0, the weights are unlocked\unheld.

// 1 = lock\hold, 0 = unlocked\unheld.  
//Change this for each shelf button
int $lockState = 1;

string $boundJoints[] = `ls "*.liw"`;
for($joint in $boundJoints)
	setAttr $joint $lockState;

if($lockState)
	print "Locked all influence weights in scene\n";
else
	print "Unlocked all influence weights in scene\n";

// optional:  Relaunch the 'Paint Skin Weights Tool' 
//to see the effect of the code:
ArtPaintSkinWeightsToolOptions;

Also see:

How is a joint's ".liw" (Lock Influence Weights) attribute connected, with regards to a skinCluster?

How can I get a windows size to always match that of it's children?

Thu, 24 Apr 2008 16:00:00 GMT

The window command has the flag -rtf (resize to fit), which will make it resize itself (bigger) to fit the child controls. However, if the UI is dynamic, or its child controls change to be smaller, when the UI is regenerated, it'll keep its larger size. How can you make it change size every time, to fit the child controls, even if the child controls shrink the overall UI size?

You need to add a call to 'remove the saved window size' at the top of the UI code:

if(`windowPref -exists "myUI_name"`)
    windowPref -remove "myUI_name";

In this example, you can change the button size however you’d like, and the UI will always resize correctly when reopened:

global proc tempWin_UI()
    {
    if(`window -exists tempWin_UI`)
        deleteUI tempWin_UI;
    if(`windowPref -exists "tempWin_UI"`)
        windowPref -remove "tempWin_UI";

    window -t "Temp Window" -rtf 1 tempWin_UI;
        columnLayout -adj 1 -co both 5;
            button -w 200 -h 200;
    showWindow;
    }
tempWin_UI;

Script Editor Replacements

Mon, 21 Apr 2008 17:55:00 GMT

Listed in no particular order...

JEDIT
jEdit is a free (and full featured) text editor, which has tools authored to let it interface directly with Maya (via the Maya's commandPort), irregardless of Maya version. That's pretty nice. As of this date, I've started using it with some success.

Download jEdit: http://www.jedit.org/
Get mel and 'python mel' context sensitive highlighting for it at Highend3d.com
Get the jEdit plugin that lets it talk to Maya at Highend3d.com
You'll need the jEdit InfoViewer plugin too.
And a tutorial on how to get it setup on Highend3d.com (you really need to read and follow this)

MAPY
Mappy isn't a text editor, but rather a free set of tools that let 'any' (so it states) text editor interface with Maya. Similar to what jEdit is doing above. I have yet to test this.

Official mappy homepage: http://rodmena.com/mapy/
Download mappy here: http://www.highend3d.com/f/mapy

MEL STUDIO PRO
I've been using Mel Studio Pro for years. Purchase and download it here. It is in my opinion the best and easiest option for scripting in Maya. It doesn't have all the debugging features of a full blown text editor, but it's convenience can't be beat.

It is a plugin in Maya (which costs $$$), that provides a Script Editor replacement, that has many features of a full-blown text editor, but lives in Maya. Check the features from the link. I can't work without it now...

Maxya Scripter
http://www.tarzworkshop.com
I had this one recommended, but I haven't had a chance to test it yet. Looks like another standalone IDE with hooks into Maya, for both mel and Python. There is both a free, and $$$ version.

Also see:

For Python: Maya 'Script Editor' style IDE

For Python: Maya 'Script Editor' style IDE

Wed, 16 Apr 2008 20:55:00 GMT

I've been looking for a LONG time, trying to find an IDE for Python that mirrored one important feature from Maya's Script Editor: Evaluate Selection, which is the ability to highlight blocks of code, and execute just that block interactively.

Maya's implementation of Python in the Script Editor can do this (since version 8.5), but what if you want to author Python outside of Maya, but still have this functionality?

After asking a lot of people, and doing a lot of searching, I finally found one:
http://www.wingware.com/

It has three versions:

Wing IDE 101 (free, but doesn't have 'Evaluate Selection')
Wing IDE Personal ($35), Wing IDE Professional ($179)

The Personal features section:
http://www.wingware.com/wingide-personal/index

Also, as of v1.7 of the 'jEdit Maya Editor Plugin' (see: Script Editor Replacements), this 'evaluate selection' functionality has been implemented (as informed by its author).

How can I qickly center the selected objects about the origin?

Mon, 14 Apr 2008 17:08:00 GMT

I often have geometry provided to me from the animation staff placed some distance away from the origin. For rigging purposes, I need them centered about the origin, with their pivots at the origin. How to get it moved back there quickly?

string $sel[] = `ls -sl`;
for($i=0;$i<size($sel);$i++)
    {
    xform -cp $sel[$i];
    vector $pos = `xform -q -ws -rp $sel[$i]`;
    move -a -ws (($pos.x)*-1) (($pos.y)*-1) (($pos.z)*-1);
    }

//  After this is done, you probably want to 
//  freeze their transforms too:
makeIdentity -a 1 $sel;

How is a joint's ".liw" (Lock Influence Weights) attribute connected, with regards to a skinCluster?

Fri, 04 Apr 2008 15:40:00 GMT

".liw" stands for "Lock Influence Weight". By default, a joint doesn't have this attribute, but when it is smooth bound to geometry, each joint receives this new attribute. It is just a custom attribute. Its output connects to the respective skinCluster's ".lockWeights[]" (.lw) imput attribute. ".lockWeights[]" is an array attribute, that can receive inputs from multiple joint.liw attrs.
There is no reference to this attribute (.liw) in the documentation, since it is a custom attr generated by the smoothBind process. You can find documentation for the ".lw" attr in the "joint" documentation.

Also see:

How can I easily hold or unhold all the influence weights on skinned geo?

WarpCat

Wed, 02 Apr 2008 21:16:00 GMT

Yes, that is me playing Rock Band.
Eric Pavey

Email: - warpcat (at) sbcglobal (dot) net -
Technical Character Director / Character TD / Technical Artist / Whatever your company calls it
At: Electronic Arts, in Redwood Shores, California
LinkedIn - Flickr - Youtube - MobyGames - RSWarrior

My other Tiddlywiki's:

CG OpenSource wiki

How can I change if I'm using Maya 'Complete', or 'Unlimited'?

Tue, 01 Apr 2008 21:48:00 GMT

Presuming you have Maya Unlimited installed (and properly licensed), there are two ways to change what features are available to you.

One way is to add this line to your Maya.env file:

MAYA_LICENSE = complete

MAYA_LICENSE = unlimited

Every time you start Maya, it will run in the defined mode.

Another way allows you to launch Maya from the command line (probably with a .bat file) with the license defined. This allows you to say, run temporarily in unlimited when you normally only run in complete (via the Maya.env).

maya -lic=unlimited

Blog

Mon, 31 Mar 2008 16:18:00 GMT

The mel wiki blog.

2008 03 31 - More Processing.
2008 03 11 - Added 'Other Links'
2008 03 07 - TROUBLESHOOTING
2008 02 18 - Processing!
2008 01 29 - Added All Subjects tiddler.
2008 01 08 - New feature: Visual Guide of UI Controls
2008 01 07 - Tiddlyspot back up. And... robots!
2008 01 04 - rain! Tiddlyspot down...
2008 01 02 - New PYTHON catagory, update wiki UI formatting.
2007 04 27 - mel wiki is born

2008 03 31

Mon, 31 Mar 2008 16:18:00 GMT

A month or so ago I talked about Processing. Since then I've started to learn it, and have been posting some of my first sketches on Flickr. Enjoy.

How can I query all the subdirs under a source dir?

Fri, 21 Mar 2008 16:54:00 GMT

The easiest way is to call out to dos using its DIR command. The default dos syntax to get a list of all the subdirs of a dir is this:

DIR /ad /s /b

You could jump through a lot of hoops with the getFileList command, but I've tried, and it's exponentially slower than doing below:
And here is how to wrapper that with mel:

// good chance the incomming path has forwardslashes
string $path = "c:/temp";

// convert to backslash:
$path = toNativePath(path);

// query the system:
string $dirList = system("DIR "+ $path + " /ad /s /b");

// and convert into an array:
string $dirs[];
tokenize $dirList "\n" $dirs;

print $dirs;
// the last index will be an empty string, FYI

You'll probably want to run fromNativePath on each array member to put them back in "forwardslash" mode when you itter through the list.

If you want to kick it up a notch, you can also use dos to look for a particular dir IN each of the paths, at the same time the list is being generated. Say, you want to find all the dirs that END with \foo. The dos command would be:

DIR /ad /s /b |FINDSTR "\\foo$"

As you can see, you pipe the return of the DIR command into the FINDSTR command, which then looks for \foo at the end up each line using the ($) regular expression. You have to use double-backslashes in front of foo, since the backslash is an escape character in regular expressions.
To wrapper that in mel would look like this:

string $dirList = system("DIR " + $path + " /ad /s /b |FINDSTR \"\\\\foo$\"");

And if you wanted to find all the .ma files in that result (notice the /ad was removed):

string $dirList = system("DIR " + $path + " /s /b |FINDSTR \"\\\\foo$\" |FINDSTR \".ma$\" ");

And that, is a lot of escape backslashes....

How can I query the color at a certain UV point on a render node?

Wed, 19 Mar 2008 23:06:00 GMT

colorAtPoint

Example given a "ramp" node:

colorAtPoint -o RGB -u .5 -v .5  ramp1;

I was told that if your UV's are tiling, UV 0 and 1 can return the same values. Querying .99999 is a safer bet.

How can I query what 'type' of data an attribute is?

Thu, 13 Mar 2008 18:13:00 GMT

getAttr -type "persp.tx";
// doubleLinear // 
getAttr -type "persp.rx";
// doubleAngle // 
getAttr -type "persp.v";
// bool // 
getAttr -type "persp.filmRollOrder";
// enum //