def nameToDag( name ):
        selectionList = om.MSelectionList()
        selectionList.add( name )
        node = om.MDagPath()
        selectionList.getDagPath( 0, node )
        return node

def Intersect(source,floor_name):

    test_intersect=getIntersect(source,floor_name)
    if test_intersect[1]==None:
        return False

    # filter geometry
    iter = om.MItDag( om.MItDag.kBreadthFirst,om.MFn.kMesh )
    old_dist=999999
    closest_mesh=None
    object_list=cmds.ls(type='transform')
    for object in object_list:
        mesh_name=object
        try:
            cmds.select(mesh_name)
        except:
            continue

        try: intersection=getIntersect(source,mesh_name)
        except:
            continue
        #print intersection
        if intersection[0]!=False:
            new_dist = distFunc(intersection[1],source)

            if new_dist<old_dist:
                closest_mesh=object
                old_dist=new_dist
                ret=intersection

    #print closest_mesh
    if closest_mesh==floor_name:
        return ret
    return False

def getIntersect(source,mesh_name):
    dag = nameToDag(mesh_name)
    meshFn = om.MFnMesh()
    meshFn.setObject( dag )
    #This is the Ray being shot
    raySource = om.MPoint(source[0],13,source[2],1)
    rayDirection = om.MVector(0,-1,0)

    pointsValue = om.MPointArray()
    polygonIdsValue = om.MIntArray()
    spaceValue = 4
    #toleranceValue = om.kMFnMeshPointTolerance
    toleranceValue =  0.01
    ret = om.MFnMesh.intersect(meshFn, raySource, rayDirection.normal(),
    pointsValue, toleranceValue, spaceValue, polygonIdsValue )
    pointLoc=[0,0,0]

    if ret==True:
        pointLoc[0]=int(pointsValue[0].x)
        pointLoc[1]=pointsValue[0].y
        pointLoc[2]=int(pointsValue[0].z)
        #print 'from: ',source, ' intersected ',mesh_name
        return ret,pointLoc

    return ret,None