【MayaPython】Is()命令行运用

简介：

示例：

首先导入头文件

import maya.cmds as cmds

列出所有对象

# list all objects
cmds.ls()

列出所有选择的对象

# List all selected objects
cmds.ls( selection=True )

列表中所有隐藏对象

# List all hilited objects
cmds.ls( hilite=True )

列出最后选择的对象

# List last selected object
cmds.ls( selection=True, tail=1 )

列出所有名为“sphere1”的对象。注意，由于sphere1是实例化的，下面的命令只列出第一个实例。

# List all objects named "sphere1". Note that since sphere1 is
# instanced, the command below lists only the first instance.
cmds.ls( 'sphere1' )

列出所有Sphere1的实例，使用全路径标签

# To list all instances of sphere1, use the -ap/allPaths flag.
cmds.ls( 'sphere1', ap=True )

列出所有选中的对象所命名的“group*”

# List all selected objects named "group*"
cmds.ls( 'group*', sl=True )

列出所有的几何体和灯光和摄像机

# List all geometry, lights and cameras in the DAG.
cmds.ls( geometry=True, lights=True, cameras=True )

列出所有的形状

# List all shapes in the dag.
cmds.ls( shapes=True )

需要注意的一点是，在列出没有任何过滤器的节点时，最好总是使用-L/Long flgg。这是因为可能有两个具有相同名称的节点(在本例中为circlel)。Ls将列出场景中所有对象的名称，具有相同名称的对象需要一个限定路径名来唯一标识对象。一个命令选择所有对象，例如“select is”将失败，因为对象查找无法解析要查找的是哪个“circler”对象。要选择所有对象，您需要以下步骤:

cmds.select(cmds.ls(sl=True))

当我们尝试在一个列表中查找一种特殊的对象类型时，一种方法是获取所有的对象然后再使用nodetype命令去筛选列表。示例：

# When trying to find a list of all objects of a specific
# type, one approach might be to list all objects and then
# use the nodeType command to then filter the list. As in:
allObjects = cmds.ls(l=True)
for obj in allObjects:
   if cmds.nodeType(obj) == 'surfaceShape':
     print obj

这里的问题是“nodetype”返回大多数的类型，在这个案例中“surfaceShape”是nurbsSurface的基本类型，因此不会打印任何内容。针对这个问题，这里的 -typ/type标签应该用于列出特定类型的对象，如:``

# The problem with this is that 'nodeType' returns the
# most derived type of the node. In this example, "surfaceShape"
# is a base type for nurbsSurface so nothing will be printed.
# To do this properly, the -typ/type flag should be used
# to list objects of a specific type as in:
allObjects = cmds.ls(type='surfaceShape')
for obj in allObjects:
    print obj

*列出所有几何体形状和它们的类型

# List all geometry shapes and their types
cmds.ls( type='geometryShape', showType=True )

列出DAG中所有叶节点的所有路径

# List all paths to all leaf nodes in the DAG
cmds.ls( dag=True, lf=True, ap=True )

列出所选节点下面的所有节点

# List all nodes below the selected node
cmds.ls( dag=True, ap=True, sl=True )

列出所有ghosting对象

# List all ghosting objects
cmds.ls( ghost=True )

有空继续

# List all dag nodes that are read-only (i.e. referenced nodes)
cmds.ls( dag=True, ro=True )

# List reference nodes associated with specific files
cmds.ls( references=True )

# List all reference nodes, including unknown and shared reference nodes
cmds.ls( type='reference' )

# Select some components and then get the list in both selected and numeric order
obj1 = cmds.polySphere( sx=20, sy=20 )
cmds.select( clear=True )

cmds.selectPref( trackSelectionOrder=1 )

cmds.select( obj1[0]+".f[100]" )
cmds.select( (obj1[0]+".f[50:55]"), add=True )
cmds.select( (obj1[0]+".f[0]"), add=True )
cmds.select( (obj1[0]+".f[56:60]"), add=True )

# regular -selection flag returns the components in compacted numeric order.
cmds.ls( selection=True )
# Result:_ [u'pSphere1.f[0]', u'pSphere1.f[50:60]', u'pSphere1.f[100]'] #

# -orderedSelection flag returns the components in the order that we selected them.
cmds.ls( orderedSelection=True )
# Result:_ [u'pSphere1.f[100]', u'pSphere1.f[50:55]', u'pSphere1.f[0]', u'pSphere1.f[56:60]'] #

# turn off tracking when we are done
cmds.selectPref( trackSelectionOrder=0 )

# init some namespace
cmds.namespace( add="A:B:C" )

# add object into namespace
cmds.namespace( set=":A:B" )
cmds.polySphere( name="obj1" )
cmds.namespace( set=":A:B:C" )
cmds.polySphere( name="obj1" )
cmds.polySphere( name="obj2" )


# The current Namespace is ":A:B:C" and relative mode is off
# List all objects and their namespace in the scene
# If the object is in the root namespace, then return root ":"
# Note that the results shown below have been elided (...) for documentation purposes.
cmds.ls( showNamespace=True )
# Result: [u'time1', u':', u'sequenceManager1', u':', u'renderPartition', u':', (...), u'A:B:obj1', u'A:B', u'A:B:C:obj1', u'A:B:C', u'A:B:C:obj2', u'A:B:C'] #

cmds.select( ":A:B:obj1", r=True )
cmds.select( ":A:B:C:obj2", add=True)


# List namespace of all objects named "obj1"
cmds.ls( "obj1", showNamespace=True, recursive=True )
# Result: [u'A:B:obj1', u'A:B', u'A:B:C:obj1', u'A:B:C'] #

# List both name and namespace of each selected object
cmds.ls( showNamespace=True, selection=True )
# Result: [u'A:B:obj1', u'A:B', u'A:B:C:obj2', u'A:B:C'] #

# set current Namespace
cmds.namespace( set=":A:B" )

# enable relative mode
cmds.namespae( relativeNames=True )

# Now the current Namespace is ":A:B" and relative mode is on
# Note that the name of the current namespace is "" in relative mode
# List both name and namespace of each selected objects
cmds.ls( showNamespace=True, selection=True )
# Result: [u'obj1', u'', u'C:obj2', u'C'] #

#make a new scene modify the transform of the camera perspective, play with the timeline and modified the camera's shape
cmds.file(force=True, new=True)
cmds.setAttr('persp.translateX', 10)
cmds.currentTime(8)
cmds.setAttr('perspShape.horizontalFilmAperture', 16)

#list all modified objects of type camera and type time
allObjects=cmds.ls(type=['camera','time'], modified=True)
print allObjects
# Result: [u'perspShape', u'time1']

cmds.ls(modified=True)
# Result: [u'persp', u'perspShape', u'time1']

cmds.ls(modified=True, excludeType='camera')
# Result: [u'persp', u'time1']