如何导入 PyMEL 核心？答案

【问题标题】：How do I import PyMEL core?如何导入 PyMEL 核心？
【发布时间】：2016-01-26 16:53:08
【问题描述】：

我正在导入 maya.standalone，对其进行初始化，然后将 pymel.core as pmc 导入我的 Maya Python 解释器，该解释器在 powershell 中运行。在这一点上，我收到了很多警告。当我打电话：xform, shape = pmc.polysphere() 后，我收到警告：name 'xform' is not defined

这是 pymel 导入的输出

> Warning: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/initialStartup.mel line 195:
> Y-axis is already the Up-axis Initialized VP2.0 renderer {   Version :
> 6.3.16.0. Feature Level 5.   Adapter : Intel(R) HD Graphics 4600   Vendor ID: 32902. Device ID : 1046   Driver :
> nvwgf2umx.dll:9.18.13.5306.   API : DirectX V.11.   Max texture size :
> 16384 * 16384.   Max tex coords : 32   Shader versions supported
> (Vertex: 5, Geometry: 5, Pixel 5).   Active stereo support available :
> 0   GPU Memory Limit : 2080 MB.   CPU Memory Limit: 15472.7 MB. }
> OpenCL evaluator is attempting to initialize OpenCL. Detected 2 OpenCL
> Platforms:  0: Intel(R) Corporation. Intel(R) OpenCL. OpenCL 1.2 . 
> Supported extensions: cl_intel_dx9_media_sharing
> cl_khr_byte_addressable_store cl_khr_d3d11_sharing
> cl_khr_dx9_media_sharing cl_khr_gl_sharing
> cl_khr_global_int32_base_atomics cl_khr_global
> _int32_extended_atomics cl_khr_icd cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics  1: NVIDIA Corporation. NVIDIA
> CUDA. OpenCL 1.2 CUDA 7.5.8.  Supported extensions:
> cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing
> cl_nv_compiler_options cl_nv_device_attribute_query
> cl_nv_pragma_unroll cl_nv_d3d9_sharing cl_nv_d3d10_shari ng
> cl_khr_d3d10_sharing cl_nv_d3d11_sharing cl_nv_copy_opts OpenCL
> evaluator choosing OpenCL platform Intel(R) Corporation. Choosing
> OpenCL Device Intel(R) HD Graphics 4600.  Device Type: GPU  Device is
> available. OpenCL device does not support out of order execution
> 
> Error: file: C:/Program
> Files/Autodesk/Maya2016/plug-ins/xgen/scripts/igInitialize.mel line
> 63: ImportError: file <maya console> line 1: No module named xgenm
> Error: Unable to execute igInitialize.mel. Unable to execute
> igInitialize.mel.Error: line 0: ImportError: file <maya console> line
> 1: No module named xgenm Error: Unable to execute xgen.mel. Unable to
> execute xgen.mel.xgmNurbsPatch [u'containerBase', u'entity',
> u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmP atch',
> u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'xgmNurbsPatch'] pymel.internal.apicache : WARNING
> : lineage for node xgmNurbsPatch is cyclical: [u'containerBase',
> u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u's urfaceShape', u'THsurfaceShape', u'xgmPatch',
> u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u' xgmNurbsPatch'] xgmSubdPatch [u'containerBase',
> u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmPatch',
> u'containerBase', u'e ntity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'xgmSubdPatch'] pymel.internal.apicache : WARNING
> : lineage for node xgmSubdPatch is cyclical: [u'containerBase',
> u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'su rfaceShape', u'THsurfaceShape', u'xgmPatch',
> u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'x gmSubdPatch'] xgmArchiveGuide
> [u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'xgmGuide', u'containerBase', u'entity',
> u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'surfaceShape', u'THsurfaceShape',
> u'xgmArchiveGuide'] pymel.internal.apicache : WARNING : lineage for
> node xgmArchiveGuide is cyclical: [u'containerBase', u'entity',
> u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u 'surfaceShape', u'THsurfaceShape', u'xgmGuide',
> u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'xgmArchiveGuide'] xgmCardGuide [u'containerBase',
> u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmGuide',
> u'containerBase', u'e ntity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'xgmCardGuide'] pymel.internal.apicache : WARNING
> : lineage for node xgmCardGuide is cyclical: [u'containerBase',
> u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'su rfaceShape', u'THsurfaceShape', u'xgmGuide',
> u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'x gmCardGuide'] xgmSphereGuide [u'containerBase',
> u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmGuide',
> u'containerBase', u 'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'xgmSphereGuide'] pymel.internal.apicache :
> WARNING : lineage for node xgmSphereGuide is cyclical:
> [u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u' surfaceShape',
> u'THsurfaceShape', u'xgmGuide', u'containerBase', u'entity',
> u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'surfaceShape', u'THsurfaceShape', u
> 'xgmSphereGuide'] xgmSplineGuide [u'containerBase', u'entity',
> u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmGuide',
> u'containerBase', u 'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u'surfaceShape',
> u'THsurfaceShape', u'xgmSplineGuide'] pymel.internal.apicache :
> WARNING : lineage for node xgmSplineGuide is cyclical:
> [u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'deformableShape', u'controlPoint', u' surfaceShape',
> u'THsurfaceShape', u'xgmGuide', u'containerBase', u'entity',
> u'dagNode', u'shape', u'geometryShape', u'deformableShape',
> u'controlPoint', u'surfaceShape', u'THsurfaceShape', u
> 'xgmSplineGuide'] AbcExport v1.0 using Alembic 1.5.4 (built May  8
> 2014 13:47:10) Error: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46:
> ImportError: file <maya console> line 1: No module named
> mtoa.lightFilters
> 
> API error detected in plugins\mtoa\extension\PxMayaNode.cpp at line
> 222 : (kFailure): Unexpected Internal Failure Error: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46:
> ImportError: file <maya console> line 1: No module named
> mtoa.lightFilters
> 
> API error detected in plugins\mtoa\extension\PxMayaNode.cpp at line
> 222 : (kFailure): Unexpected Internal Failure Error: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46:
> ImportError: file <maya console> line 1: No module named
> mtoa.lightFilters
> 
> API error detected in plugins\mtoa\extension\PxMayaNode.cpp at line
> 222 : (kFailure): Unexpected Internal Failure Error: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46:
> ImportError: file <maya console> line 1: No module named
> mtoa.lightFilters
> 
> API error detected in plugins\mtoa\extension\PxMayaNode.cpp at line
> 222 : (kFailure): Unexpected Internal Failure 00:00:00   359MB ERROR  
> | [mtoa] [xgenTranslator] Could not find xgen_procedural in search
> path $ARNOLD_PLUGIN_PATH Error: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46:
> ImportError: file <maya console> line 1: No module named
> mtoa.api.extensions
> 
> API error detected in plugins\mtoa\extension\ExtensionsManager.cpp at
> line 571 : (kFailure): Unexpected Internal Failure Error: file:
> C:/Program Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel
> line 46: ImportError: file <maya console> line 1: No module named
> mtoa.api.extensions
> 
> API error detected in plugins\mtoa\extension\ExtensionsManager.cpp at
> line 571 : (kFailure): Unexpected Internal Failure Error: file:
> C:/Program Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel
> line 46: ImportError: file <maya console> line 1: No module named
> mtoa.api.extensions
> 
> API error detected in plugins\mtoa\extension\ExtensionsManager.cpp at
> line 571 : (kFailure): Unexpected Internal Failure Error: file:
> C:/Program Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel
> line 46: ImportError: file <maya console> line 1: No module named
> arnold
> 
> API error detected in plugins\mtoa\Main.cpp at line 770 : (kFailure):
> Unexpected Internal Failure 00:00:00   362MB ERROR   | Failed to
> import python module 'arnold' Error: Failed to import python module
> 'arnold' aiSkyDomeLight [u'containerBase', u'entity', u'dagNode',
> u'shape', u'geometryShape', u'locator', u'THlocatorShape',
> u'SphereLocator', u'containerBase', u'entity', u'dagNode', u'shape',
> u'geo metryShape', u'locator', u'THlocatorShape', u'aiSkyDomeLight']
> pymel.internal.apicache : WARNING : lineage for node aiSkyDomeLight is
> cyclical: [u'containerBase', u'entity', u'dagNode', u'shape',
> u'geometryShape', u'locator', u'THlocatorShape', u'Sphere Locator',
> u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'locator', u'THlocatorShape', u'aiSkyDomeLight'] aiSky
> [u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape',
> u'locator', u'THlocatorShape', u'SphereLocator', u'containerBase',
> u'entity', u'dagNode', u'shape', u'geometryShap e', u'locator',
> u'THlocatorShape', u'aiSky'] pymel.internal.apicache : WARNING :
> lineage for node aiSky is cyclical: [u'containerBase', u'entity',
> u'dagNode', u'shape', u'geometryShape', u'locator', u'THlocatorShape',
> u'SphereLocator',  u'containerBase', u'entity', u'dagNode', u'shape',
> u'geometryShape', u'locator', u'THlocatorShape', u'aiSky'] Error:
> file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46:
> initializePlugin function failed (mtoa) AbcImport v1.0 using Alembic
> 1.5.4 (built May  8 2014 13:47:10) BifrostMain plug-in loaded (built Feb 26 2015 18:01:51) Error: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46:
> ImportError: file C:/Program
> Files/Autodesk/Maya2016/plug-ins/xgen/plug-ins/xgenMR.py line 9: No m
> odule named xgenm Warning: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46:
> Failed to run file: C:/Program
> Files/Autodesk/Maya2016/plug-ins/xgen/plug-ins/xgenMR.py pymel : ERROR
> : Failed to get controlCommand list from xgenMR pymel : ERROR : Failed
> to get modelEditorCommand list from xgenMR pymel : ERROR : Failed to
> get command list from xgenMR pymel : ERROR : Failed to get
> constraintCommand list from xgenMR pymel.core : ERROR : Failed to get
> depend nodes list from xgenMR Error: file: C:/Program
> Files/Autodesk/Maya2016/scripts/startup/autoLoadPlugin.mel line 46: 
> (xgenMR)
> >>>

我正在阅读 Practical Maya Programming 一书，这是书中的文字：

现在我们将开始深入研究 Maya 和 PyMEL。让我们从在 mayapy 解释器中初始化 Maya，这样我们就可以使用只是标准的 Python 功能。我们通过调用来做到这一点 maya.standalone.initialize，如下代码所示：

>>> import maya.standalone
>>> maya.standalone.initialize()
>>> import pymel.core as pmc
>>> xform, shape = pmc.polySphere()

pymel.core 的导入会自动隐式调用 maya.standalone.initialize，但我是这样做的明确地在这里，所以很清楚发生了什么。未来，您可以通常跳过对 maya.standalone.initialize 的调用并仅导入 pymel.core。

我们可以发现很多关于这些 PyMEL 对象的信息，代表 Maya 节点，使用基本的 Python。例如，要查看我们任何一个对象的类型，我们可以使用内置类型函数（我们将在本章后面更深入地研究类型）。

谁能解释我在解释器中遇到的错误并提供解决方案？

【问题讨论】：

标签： python maya pymel

【解决方案1】：

当您在 Windows 上时，请确保您没有使用 Powershell ISE。只需使用标准 Powershell。

正如@Boon 所说，这些错误中的大多数来自插件和 Maya 的一些本可以写得更好的东西。

当您专注于学习编程时，您不需要这些插件。您可以从交互式 Maya 会话中禁用它们：

打开 Maya。
选择 Windows->设置/首选项->插件管理器
为所有不在的插件关闭“加载”和“自动加载” 顶部：即 Xgen、Bifrost、Substance、mtoa 等。
关闭 Maya。

现在在你的 shell 中再试一次：

mayapy
import maya.standalone
maya.standalone.initialize()
import pymel.core as pm

此时，我看到一个关于 Y-Up 的警告，以及一些 Alembic 版本信息，而没有其他内容。那里没什么好担心的。

提示是>>>，这是一件好事。你现在应该可以输入 pymel 命令了：键入（一次查看输出）：

pm.about(version=True)
pm.polySphere() 
pm.ls(type="mesh")

编辑

如果您使用的是 powershell 并设置了配置文件，则可以通过将以下行添加到您的 profile.ps1 来节省一些时间：

function ms { mayapy -i  -c "import maya.standalone;maya.standalone.initialize();import pymel.core as pm;print('maya standalone initialized and pymel.core imported as pm')" }

现在您可以打开一个 powershell，输入 ms 并开始编码。

【讨论】：

【解决方案2】：

（这不是一个完整的答案，但我是菜鸟，所以我不能发表评论。）

一堆警告，看起来像

xgmNurbsPatch [u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape', u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmPatch', u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape', u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmNurbsPatch']
# Warning: pymel.internal.apicache : lineage for node xgmNurbsPatch is cyclical: [u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape', u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmPatch', u'containerBase', u'entity', u'dagNode', u'shape', u'geometryShape', u'deformableShape', u'controlPoint', u'surfaceShape', u'THsurfaceShape', u'xgmNurbsPatch'] #

（我认为）是 Maya 2016 的一个问题，您可能不需要担心什么。

我在脚本编辑器中工作，而不是使用 maya.standalone。当我将 Pymel 导入 Maya 2016 时，我收到了 6 个针对各种“xgm”类的警告，和你一样。在以前的 Maya 版本中没有发生这种情况。

至于错误，mtoa/Arnold 和 xgen 都是插件（并且您的所有错误似乎都与插件加载有关）。也许你可以禁用它们？抱歉，我没有在 Maya 主应用程序之外使用过 Maya Python 解释器。

编辑：我看到其他人（或者你？）在 XGen、Arnold 和 Maya 2016 中遇到了类似的错误： http://forums.cgsociety.org/archive/index.php?t-1287693.html

【讨论】：

感谢您的意见.. 给您一个支持以帮助您在未来发表评论:)