Maya Python Decorators

decorators.py

import msvcrt
import maya.cmds as cmds
import functools

def interactive(fn):
    EXIT = "exitObject"
    @functools.wraps(fn)
    def wrapped(*args, **kwargs):
        if cmds.objExists(EXIT):
            cmds.delete(EXIT)
        while(not fn()):
            # refresh is what allows user interaction as this is happening
            cmds.refresh()

            # this is our emergency exit from the infinite loop
            # assign the creation of this object to a shortcut
            if cmds.objExists(EXIT):
                print "Escaping . . . "
                cmds.delete(EXIT)
                break
    return wrapped

# only queries the selection once to save processing
# wrapping like this could allow passing arguments to interactive (such as selection or frame count)
def groundCollision():
    sel = cmds.ls(sl = True)
    if sel:
        @interactive
        def collide():
            x = cmds.getAttr("{0}.ty".format(sel[0]))
            if x < 0:
                cmds.setAttr("{0}.ty".format(sel[0]), 0)
        collide()

# intractive could accept a max duration before exiting, or the name of the exit object
@interactive
def recordAnimation():
    sel = cmds.ls(sl = True)
    if sel:
        cmds.setKeyframe(sel)
    cmds.currentTime(cmds.currentTime(q = True) + .3, e = True)

    # optional: this allows a natural exit
    #if cmds.currentTime(q = True) > 100:
        #return True

# thse will run in consecutive order
recordAnimation()
# needs selection beforehand
groundCollision()