Maya Mel Script - Drop Pivot to Bottom of object?

I see someone asked this before (for example: here). So how to automatically set the pivot to the bottom of the model?

To do that:

Step 1: find the bottom point.

Step 2: Set the pivot to the bottom point.

Here is the mel script help you do that:

    string $sel[]= `ls -sl`;

    //$sel[0] != "" to check if the first item is empty, but `size $sel` == 1 already cover that
    if(`size $sel` > 0)
    {
        int $vtxIdx;
        int $vCount[];
        float $lowestY = 2147483647.0;
        float  $crtY = 0.0;
        float $pos[];

        string $item;
        for ($item in $sel)
        {
            $vCount = `polyEvaluate -vertex $item`; //Get vertex count
            for ($vtxIdx = 0; $vtxIdx < $vCount[0]; $vtxIdx++)//Loop through vetex
            {
                $pos = `xform -q -ws -t ($item+".vtx["+$vtxIdx+"]")`;//Get vertex position
                $crtY = $pos[1];
                if($crtY < $lowestY)
                {
                    $lowestY = $crtY;//Get the lowest Y
                }
            }
            $pos = `xform -q -ws -t ($item)`;
            xform -ws -a -piv $pos[0] $lowestY $pos[2] ($item);
            print ($lowestY);
        }

    }

Usage:

step 1: select the objects that need to set pivot to bottom

step 2: execute the script

The pivot point should be set like this If your requirement is: the pivot point must be inside the model, then you should edit this script a little bit.