Maya Mel Script - Drop Pivot to Bottom of object? - mel

Question

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

Answer 1

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.

Answer 2

Thank you! I used your code above, 123iamking but I found I wanted to drop pivot to world y0 instead of bounding box.
so I changed some stuff around.
Works on Maya 2020.
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)
{
float $pos[];
string $item;
for ($item in $sel)
{
xform -ws -a -cp;
CenterPivot;
$pos = `xform -q -ws -a -piv ($item)`;//Get piv position
xform -ws -a -piv $pos[0] 0 $pos[2] ($item); //set pivot to 0 in world y
}
};