xform_to_locator.py

from maya import cmds
import maya.OpenMaya as om
import math

LOCATOR_NAME = '_loc'

def get_rotation_from_matrix(matrix_list, rot_order):
    # Create an empty MMatrix:
    mMatrix = om.MMatrix() # MMatrix
    # And populate the MMatrix object with the matrix list data:
    om.MScriptUtil.createMatrixFromList(matrix_list, mMatrix)

    #-------------------------------------------
    # Part 2, get the euler values
    # Convert to MTransformationMatrix to extract rotations:
    mTransformMtx = om.MTransformationMatrix(mMatrix)
    # Get an MEulerRotation object
    eulerRot = mTransformMtx.eulerRotation() # MEulerRotation
    # Update rotate order to match original object, since the orig MMatrix has
    # no knoweldge of it:
    eulerRot.reorderIt(rot_order)

    # Convert from radians to degrees:
    angles = [math.degrees(angle) for angle in (eulerRot.x, eulerRot.y, eulerRot.z)]
    return angles


if __name___ == "__main__":
    
    nodes = cmds.ls(sl=1)

    start = cmds.timerX()
    # code that is being timed

    for node in nodes:
        # Uncomment this if you know what you're doing
        # if not cmds.nodeType(node) == 'transform': continue

        loc = cmds.spaceLocator(name=node + LOCATOR_NAME)
        rot_order = cmds.getAttr(loc[0] + '.rotateOrder')

        keyframes = cmds.keyframe(node, q=True)
        keyframes = list(set(keyframes))


        for key in keyframes:

            matrix_list = cmds.getAttr(node + '.worldMatrix', time=key)
            # Translation
            cmds.setKeyframe(loc[0], attribute='translateX', value=matrix_list[12], time=key)
            cmds.setKeyframe(loc[0], attribute='translateY', value=matrix_list[13], time=key)
            cmds.setKeyframe(loc[0], attribute='translateZ', value=matrix_list[14], time=key)
            # Rotation
            angles = get_rotation_from_matrix(matrix_list, rot_order)
            cmds.setKeyframe(loc[0], attribute='rotateX', value=angles[0], time=key)
            cmds.setKeyframe(loc[0], attribute='rotateY', value=angles[1], time=key)
            cmds.setKeyframe(loc[0], attribute='rotateZ', value=angles[2], time=key)

    # Done
    cmds.currentTime(cmds.currentTime(q=True))

    totalTime = cmds.timerX(startTime=start)
    print "Total time: ", totalTime