Before you read anything below, read this list first

• Python can use almost all the mel command, maya.cmds is a module that simply wraps MEL commands in Python syntax, like

  import maya.cmds as cmds; cmds.sphere()

• Python can run directly in mel mode, like

  import maya.mel as mel; skin = mel.eval('findRelatedSkinCluster "'+geoName+'"')

• Python can call maya C++ API (maya api 1.0), like

  import maya.OpenMaya as om
  import maya.OpenMayaAnim as oma
  aim_dir = cmds.xform(myLoc, q=1, t=1, ws=1)
  aim_vec = om.MVector(*aim_dir)
  rot_quaternion = myObj_axis_vec.rotateTo(aim_vec)
  # myObj_axis_vec is set as x axis direction
  myObj_fnTransform.rotateBy(rot_quaternion)
  # myObj_fnTransform is set as the transform api function object

• Python can call maya C++ API 2.0 (partially since maya 2013, and still partially in 2015, maybe better in latest)

  import maya.api.OpenMaya as om2
  aim_dir = cmds.xform(myLoc, q=1, t=1, ws=1)
  aim_vec = om2.MVector(aim_dir) # can take python list automatically
  # also, no need MScriptUtil for pointer to value stuff
  # can directly return value like normal python
  # also, sometimes faster than api 1.0

  • ref:
    • maya 2010 api 1.0 ref: http://download.autodesk.com/us/maya/2011help/API/main.html
    • maya 2013 api 2.0 doc: http://docs.autodesk.com/MAYAUL/2013/ENU/Maya-API-Documentation/python-api/index.html
    • maya 2017 api 2.0 doc: http://help.autodesk.com/view/MAYAUL/2017/ENU/?guid=__files_GUID_AC9B3C66_90FE_493F_A7B2_44ABBA77CED2_htm
• Python can run almost every python module, as long as compatible with maya's internal python version, and add into sys.path.

• Info on PyMel:
  • PyMel is created to combine above maya.cmds, maya.mel, maya.OpenMaya (api 1.0) into a seamless python module, that do the coding style translation and with extra with object-oriented features and an extra large library of useful modules; thus a python module to call those maya python modules
  • for me, I currently still prefer handle it directly than learning a new syntax called pymel

• to do and merge into this
  • old cgwiki:mel
  • old cgwiki:python

• moved all over from my old cgwiki:maya_api

• Simple example, the DAG describes how an instance of an object is constructed from a piece of geometry.
• *DAG* defines elements such as the position, orientation, and scale of geometry, and DAG is composed of two types of DAG nodes, transforms and shapes.
  1. Transform nodes : Maintain transformation information (position, rotation, scale, etc.) as well as parenting information.
     • For example, if you model a hand, you would like to apply a single transformation to rotate the palm and fingers, rather than rotating each individually-in this case the palm and fingers would share a common parent transformation node.
  2. Shape nodes : Reference geometry and do not provide parenting or transformation information.
     • For example, when you create a sphere, you create both a shape node (the sphere) and a transformation node that allows you to specify the sphere's position, scale, or rotation. The transformation node's shape node is its child.

• DagPath is a set of nodes which uniquely identifies the location of a particular node or instance of a node in the graph.
• The path represents a graph ancestry beginning with the root node of the graph and containing, in succession, a particular child of the root node followed by a particular child of this child, etc., down to the node identified by the path.
• For instanced nodes, there are multiple paths which lead from the root node to the instanced node, one path for each instance. Paths are displayed in Maya by naming each node in the path starting with the root node and separated by the vertical line character, “|”.

• All data within maya is contained within seperate connectable nodes (in maya terminology, dependency nodes). the nodes that accept and output data are called dependency graph nodes.
• It is used for animation (deform, simulation, audio) and construction history (model creation)
• All of these node types, are defined by the enumeration MFn::Type. For example, a textured polygonal mesh may be constructed from
  • an MFn::kMesh node for the polygonal surface shape
  • an MFn::kTransform to position the mesh in the scene
  • an MFn::kLambert node for the surface material
  • an MFn::kFileTexture node for the surface texture
• If at anytime, you need to find out how a set of nodes are connected, then you can use the hypergraph within maya, to show you a graphical representation of the scene data. It is worth remembering that the hypergraph only displays connections between attributes; It does not show the connections between a transform and the child objects underneath it. The outliner can do that for you.

• These are related but different systems, used for different purposes.
• Unlike DAG nodes, dependency graph nodes can be cyclic, meaning they can pass information both directions. (ref)
• The DAG relates to the DG in that every DAG node is implemented as a DG node, both shapes and transforms. The only “non-DG” component of the DAG is the parenting relationship.
• The dependency graph (DG) is a collection of entities connected together. Unlike the DAG, these connections can be cyclic, and do not represent a parenting relationship. Instead, the connections in the graph allow data to move from one entity in the graph to another. The entities in the graph which accept input, and output data, are called dependency graph nodes.
• Most objects in Maya are dependency graph nodes, or networks of nodes (several nodes connected together). For example, DAG nodes are dependency graph nodes, and shaders are networks of nodes.

• MPxNode: base of DG node
  • virtual compute(const MPlug& plug, MDataBlock& data)
    • MDataHandle inputDH=data.inputValue(inAttrName, &status); float result=calFun( inputDH.asFloat() );
    • MDataHandle outputDH=data.outputValue(outAttrName); outputDH.set(result);
    • data.setClean(plug)
  • return MS::kSuccess;
  • static void* creator()
  • static MStatus initialize()
  • MTypeId yourNode::id( 0x80000); (any local id bet. 0x0000 0000 to 0x0007 ffff)
  • attr: readable(output?); writable(input?); connectable;storable(toFile?);settable;
  • attr: multi(array?); keyable; hidden
  • addAttribute(inAttrName); attributeAffects(whichInput, output)
• MPxLocatorNode: DG-DAG-locator node, not renderable
• MPxIkSolverNode: DG-IK solver (doSolve())
• MPxDeformerNode: DG-deformer (deform())
• MPxFieldNode: DG-dynamic field (compute())
• MPxEmitterNode: DG-emitter
• MPxSpringNode: DG-dynamic spring (applySpringLaw())
• MPxManipContainer: DG-manipulator
• MPxSurfaceShape: DG-DAG-shape
• MPxObjectSet: set
• MPxHwShaderNode: hardware shader
• MPxTransform: matrics (MPxTransformMatrix)

• simple attribute: attribute has only 1 plug
  • it also can hold array data, like pointArray, intArray
  • MFnNumericAttribute
  • MFnTypedAttribute
• array attribute: attribute has array of plugs, each element plug has own value or connection or null, all of them under the top array plug.
  • MFnAttribute::setArray()
• compound attribute: a collection of other attributes, called child attribute
  • MFnCompoundAttribute
    • example, color

      color1R = nAttr.create( “color1R”, “c1r”,MFnNumericData::kFloat);
      color1G = nAttr.create( “color1G”, “c1g”,MFnNumericData::kFloat);
      color1B = nAttr.create( “color1B”, “c1b”,MFnNumericData::kFloat);
      color1 = nAttr.create( “Sides”, “c1”, color1R, color1G,color1B);
      nAttr.setStorable(true);
      nAttr.setUsedAsColor(true);
      nAttr.setDefault(1.0f, 1.0f, 1.0f);
      addAttribute(color1R);
      addAttribute(color1G);
      addAttribute(color1B);
      addAttribute(color1);
      attributeAffects(color1R, color1);
      attributeAffects(color1G, color1);
      attributeAffects(color1B, color1);
      attributeAffects(color1, aOutColor);

• dynamic attribute: a attribute is dynamically created when needed.
  • MFnDependencyNode::kLocalDynamicAttr

• MDataBlock is a storage object holds DG node's data during DG node's compute() method
• MDataHandle is a reference into MDataBlock's plugs, and get or set onto plug
• Data creator is for creating data to be into MDataBlock, like output plug of another node,
  • mostly for heavy data like mesh
  • MFnData (MFnMeshData, DAG-MFnMesh, MFnNurbsSurfaceData, DAG-MFnNurbsSurface)

• static MObject color1R,color1G,color1B,color1;
• static MObject aOutColorR, aOutColorG, aOutColorB,aOutColor;
• static MObject aNormalCameraX, aNormalCameraY,aNormalCameraZ, aNormalCamera;
• static MObject aPointCameraX, aPointCameraY,aPointCameraZ, aPointCamera;
• void MStatus compute( const MPlug&, MDataBlock& );

• textures/2d
• textures/3d
• textures/environment
• shader/surface
• shader/volume
• shader/displacement
• light
• utility/general
• utility/color
• utility/particle
• imageplane
• postprocess/opticalFX

note: shader=material

• example, Blinn creation

  shadingNode -asShader blinn; 
  // same as: 
  createNode blinn;
  connectAttr blinn1.message defaultShaderList1.shaders;

  • if creation option checked “with shading group”

    sets -renderable true -noSurfaceShader true -empty -name blinn1SG;
    connectAttr -f blinn1.outColor blinn1SG.surfaceShader;

• example, volume creation

  shadingNode -asShader lightFog;
  sets -renderable true -noSurfaceShader true -empty -name lightFog1SG;
  connectAttr -f lightFog1.outColor lightFog1SG.volumeShader;

• example, displacement creation

  shadingNode -asShader displacementShader;
  sets -renderable true -noSurfaceShader true -empty -name displacementShader1SG;
  connectAttr -f displacementShader1.displacement displacementShader1SG.displacementShader;

• example, texture 2d

  shadingNode -asTexture checker; // means: 1. createNode checker; 2. add to multilister
   
  // if with option checked "With New Texture Placement" 
  shadingNode -asUtility place2dTexture; 
  connectAttr place2dTexture1.outUV checker1.uv;
   
  // if with option checked "As Projection"
  shadingNode -asTexture projection;
  shadingNode -asUtility place3dTexture;
  connectAttr place3dTexture1.wim[0] projection1.pm;
  connectAttr checker1.outColor projection1.image;
   
  // else with option checked "as stencil"
  shadingNode -asTexture stencil;
  shadingNode -asUtility place2dTexture;
  connectAttr place2dTexture2.outUV stencil1.uv;
  connectAttr checker1.outColor stencil1.image;
   
  // ------ 3d tex
  shadingNode -asUtility place3dTexture;
  connectAttr place3dTexture2.wim[0] brownian1.pm;

• MPxSurfaceShape: with component handling function and DG node function
  • MPxSurfaceShapeUI: drawing and selection functions
  • MPxGeometryIterator: component iterator
  • MPxGeometryData: pass geo data
• MPxNode

• shape component:
  • MFnComponent
    • MFnSingleIndexedComponent: vertices
    • MFnDoubleIndexedComponent: cvs
    • MFnTripleIndexedComponent: lattice points

• shape component access:
  • MFnComponent
    • MFn::kMeshVertComponent : vtx[]
  • override access
    • MPxSurfaceShape::componentToPlugs(MObject& componet, MSelectionList& list)
  • check call process (name, index, range):
    • MPxSurfaceShape::matchComponent(const MSelectionList& item, const MAttributeSpecArray& spec, MSelectionList& list)
  • iterate component:
    • MPxGeometryIterator

      virtual MPxGeometryIterator* geometryIteratorSetup(MObjectArray&, MObject&, bool );
      virtual bool acceptsGeometryIterator( bool writeable );
      virtual bool acceptsGeometryIterator( MObject&,bool, bool );

  • component manipulator
    • MPxSurfaceShape::TransformUsing (matrix, components)
    • to speedup of setting attribute values, use MPxNode::forceCache, to access datablock and set directly without compute, vertexOffsetDirection if normal used.
  • tweak storing vs no-history access
    • set setAttr/getAttr behavior, use MFnAttribute::setInternal
  • connection around geometry data
    • define from MPxGeomtryData based on MPxData
    • and iterator: virtual MPxGeometryIterator* iterator(MObjectArray& MObject&, bool);
  • File save data
    • define writeASCII, writeBinary from MPxData

• custom deform attributes
  • MPxGeometryData
  • localShapeInAttr
  • localShapeOutAttr
  • worldShapeOutAttr
  • MPxGeomtryIterator
  • match
  • createFullVertexGroup
  • geometryData

• polygon component
  • vertices (vtx[id] →float pos[3])
  • edges (edge[id] → {vtxID_s, vtexID_e})
  • faces (fe[ids], face[id] → fe_offset)
  • face vertices & uv ( face[id] → fv[id]; fe[ids] → {v_s, v_e})
• polygon attribute:
  • inMesh (storable)
  • outMesh
  • cachedInMesh (storable)
  • pnts (tweaks) (position offset for each vertex)
    • = modifier → inMesh → tweaks → outMesh
    • or = outMesh
    • or cachedInMesh → tweaks → outMesh -cp→ cachedInMesh
• polygon access, modify, create
  • MItMeshPolygon (Face comp, f-v, f-e, adjacent comp, uv, color-per-v, smooth info)
  • MItMeshEdge (Edge comp, e-f, e-v, edge smooth, adjacent comp)
  • MItMeshVertex, MItMeshFaceVertex (pos, v-f, v-e, normal, uv, color, adj comp) (f-fv_id, normal, uv, color)
  • MFnMesh (mesh operate on comp)
    • meshFn.numPolygons();
    • meshFn.numEdges();
    • meshFn.numVertices();
    • meshFn.polygonVertexCount();
    • meshFn.numUVs();
• polygon history
  • original polyShape → modifier → modifier → (new modifier)→ polyNode
• polygon custom modifier
  • MPxCommand
    • MStatus doModifyPoly();
    • MStatus redoModifyPoly();
    • MStatus undoModifyPoly();
• polygon exporter
  • class polyExporter, polyWriter, polyRawExporter, polyRawWriter

• launch Maya GUI interface with custom path setting and startup cmd or script at launch time, windows batch example

  set MAYA_MODULE_PATH=Z:/example_external_folder/maya/modules/2014;%MAYA_MODULE_PATH% 
  set MAYA_SHELF_PATH=Z:/example_external_folder/maya/shelves/2014;%MAYA_SHELF_PATH%
  set MAYA_PRESET_PATH=Z:/example_external_folder/maya/presets/2014;%MAYA_PRESET_PATH%
   
  set MAYA_PLUG_IN_PATH=Z:/example_external_folder/maya/plug-ins/2014;%MAYA_PLUG_IN_PATH%
  set MAYA_PLUG_IN_LIST=fbxmaya.mll;objExport.mll;%MAYA_PLUG_IN_LIST%
   
  set MAYA_SCRIPT_PATH=Z:/example_external_folder/maya/scripts/2014;%MAYA_SCRIPT_PATH%
  set MAYA_SCRIPT_PATH=Z:/example_external_folder/maya/scripts/2014/custom2;%MAYA_SCRIPT_PATH%
  set MAYA_SCRIPT_PATH=Z:/example_external_folder/maya/scripts/2014/custom3;%MAYA_SCRIPT_PATH%
   
  set PYTHONPATH=Z:/example_external_folder/maya/Python/2014/Lib;%PYTHONPATH%
  set PYTHONPATH=Z:/example_external_folder/maya/tools/2014;%PYTHONPATH%
   
  "C:\path_to_maya\maya.exe" -c "python(\"execfile('Z:/path_to_custom_script_to_run_on_start/custom.py')\")"

• process file with Maya in commandline only interface with “maya” in mac/linux, with “mayabatch.exe” with win

maya flags

• set viewport display color

  cmds.displayColor('locator', 17, c=1, dormant=1) # 17, gold color
  # active=1 if for active color

• list all maya UI element and close some

  allWindows = cmds.lsUI(windows=1)
  toClose_win_list = [x for x in allWindows if x not in ['CommandWindow','ConsoleWindow','MayaWindow','ColorEditor'] ]
  for each in toClose_win_list :
      cmsd.deleteUI(each)

• select tool filter

  cmds.selectType(allObjects=0) # query by cmds.selectType(allObjects=1, q=1)
  cmds.selectType(locator=1)

• display layer management

  cmds.select(objList)
  cmds.createDisplayLayer(name="objList_layer", number=1, nr=1) # create layer from selection
   
  cmds.setAttr(layer + ".displayType", 2) # 0 normal, 1 template, 2 reference

• display defined curve smoother, (note only during current maya session, restart maya will back to default)

  cmds.displaySmoothness(['guide_R_path', 'guide_L_path'],divisionsU=3, divisionsV=3, pointsWire=16, pointsShaded=4, polygonObject=3)

• get panel currently in focus

  cmds.getPanel(wf=1)

• get panel currently under pointer

  cmds.getPanel(up=1)

• list maya UI
  ref： (scan through all Maya UI elements) http://ewertb.soundlinker.com/mel/mel.101.php
  

  cmds.lsUI(type='tabLayout') # list all maya ui tab layout object
  cmds.lsUI(windows=1) # list all window
   
  # trick cmds
  cmds.lsUI(controlLayouts=1, l=1)
  layoutType = cmds.objectTypeUI('AErootLayout')
  childs = cmds.layout('AErootLayout', q=1, childArray=1)

• list maya UI's child and object type and parent

  # most maya layout has a -childArray flag to get child
  cmds.tabLayout("compEdTab",q=1,childArray=1)
  # get UI type
  cmds.objectType("compEdTabChild5")
  # then continue call with the object's related cmd
   
  # to get parent
  cmds.tabLayout("compEdTab",q=1,parent=1)

• toggle maya window title bar visible and edit

  cmds.window('MayaWindow', e=1, titleBar=(not cmds.window('MayaWindow', q=1, titleBar=1)))
  # hide title bar (true no UI by: press ctrl+space; then run this cmd)
   
  newT="Autodesk Maya 2009 x64 Unlimited: untitled | cool"
  cmds.window('MayaWindow', e=1, title=newT) # mel name as $gMainWindow

• toggle outline window

  if cmds.window('outlinerPanel1Window',ex=1):
      cmds.deleteUI('outlinerPanel1Window')
  else:
      mel.eval('OutlinerWindow')

• ignore a set of scripting/cmd in undo history

  # ref: http://cgbreakdown.com/Blog/tools-and-scripts-maya-undo
  import maya.mel as mel
  import maya.cmds as cmds
  # nextFrame ('Alt+.')
  cmds.undoInfo(stateWithoutFlush=0)
  mel.eval('playButtonStepForward')
  cmds.undoInfo(stateWithoutFlush=1)
   
  # previousFrame ('Alt+,')
  cmds.undoInfo(stateWithoutFlush=0)
  mel.eval('playButtonStepBackward')
  cmds.undoInfo(stateWithoutFlush=1)
   
  # nextKey ('.')
  cmds.undoInfo(stateWithoutFlush=0)
  cmds.currentTime(cmds.findKeyframe(timeSlider=1,which='next'), e=1)
  cmds.undoInfo(stateWithoutFlush=1)
   
  # previousKey (',')
  cmds.undoInfo(stateWithoutFlush=0)
  cmds.currentTime(cmds.findKeyframe(timeSlider=1,which='previous'), e=1)
  cmds.undoInfo(stateWithoutFlush=1)
   
  # firstKey
  cmds.undoInfo(stateWithoutFlush=0)
  cmds.currentTime(cmds.findKeyframe(which='first'), e=1)
  cmds.undoInfo(stateWithoutFlush=1)
   
  # lastKey
  cmds.undoInfo(stateWithoutFlush=0)
  cmds.currentTime(cmds.findKeyframe(which='last'), e=1)
  cmds.undoInfo(stateWithoutFlush=1)

• group a set of scripting in undo history

  cmds.undoInfo(openChunk=1)
  # your scripting block here
  cmds.undoInfo(closeChunk=1)

• get maya global variable to python name, example

  mel.eval('global string $gChannelBoxName; $temp=$gChannelBoxName;')

• toggle channel box nice and short names

  main_cb = 'mainChannelBox'
  next_state = not cmds.channelBox(main_cb, q=1, nn=1)
  cmds.channelBox(main_cb, e=1, ln=next_state, nn=next_state)

• toggle script editor echo and clear echo

  cmdPanel = 'cmdScrollFieldReporter1'
  next_state = not cmds.cmdScrollFieldReporter(cmdPanel, q=1, eac=1)
  cmds.cmdScrollFieldReporter(cmdPanel, e=1, eac=next_state)
   
  # clear echo
  cmds.cmdScrollFieldReporter(cmdPanel, e=1, clear=1)

• create script editor

  if cmds.cmdScrollFieldExecuter(ui_name, q=1, ex=1):
      cmds.deleteUI(ui_name)
  mui = cmds.cmdScrollFieldExecuter(ui_name, st='python', sth=0, sln=1)# width=200, height=100)
   
  selected_text = cmds.cmdScrollFieldExecuter(mui, q=1, selectedText=1)
  # change selected or insert text
  cmds.cmdScrollFieldExecuter(mui, e=1, insertText='#==== '+selected_text+' ====')
   
  # set search text and search next
  cmds.cmdScrollFieldExecuter(mui, e=1, searchDown=1, searchWraps=1, searchMatchCase=0, searchString=text)
  res = cmds.cmdScrollFieldExecuter(mui, q=1, searchAndSelect=1) # 1 or 0
   
  # go to line number
  cmds.cmdScrollFieldExecuter(mui, e=1, currentLine=lineNum)
   
  # get script editor whole text
  script_text = cmds.cmdScrollFieldExecuter(mui, q=1, t=1)

• create script history logger

  mui = cmds.cmdScrollFieldReporter(ui_name)#, width=200, height=100)
   
  # clear history
  cmds.cmdScrollFieldReporter(mui, e=1, clr=1)

• open component editor and show skining tab

  mel.eval('ComponentEditor')
  # active smooth skin tab
  tab_name_list = cmds.tabLayout("compEdTab", q=1, tabLabel=1)
  for i in range(len(tab_name_list)):
      if tab_name_list[i] == "Smooth Skins":
          cmds.tabLayout("compEdTab",e=1, selectTabIndex=i+1)

• add selected node into hyperShade and related

  for each in cmds.ls(sl=1):
      cmds.hyperGraph("graph1HyperShadeEd", e=1, addDependNode=each )
   
  cmds.hyperGraph("graph1HyperShadeEd", e=1, addBookmark=1)
  newBookmark = cmds.hyperGraph("graph1HyperShadeEd", q=1, bookmarkName=1) # return recent created mark
  cmds.setAttr(newBookmark+".description", "my bookmark note", type="string") 

• add selected node in nodeEditor and related

  for each in cmds.ls(sl=1):
      cmds.nodeEditor('nodeEditorPanel2NodeEditorEd',e=1, addNode=each)
   
  cmds.getPanel(scriptType="nodeEditorPanel") # add NodeEditorEd at the end to get the nodeEditor object
  cmds.nodeEditor('nodeEditorPanel2NodeEditorEd', q=1, getNodeList=1)

• toggle channel box long short name display

  import maya.mel as mel
  mel.eval('setChannelLongName(!`channelBox -query -nn $gChannelBoxName`)')

• maya mel button with python function with parameter

  def process_func(data):
      print(data)
  cmds.button( command = lambda *args: process_func('one')

• show GraphEditor

  # get panel by name
  whichPanel = cmds.getPanel(withLabel='Graph Editor')
  cmds.scriptedPanel(whichPanel, e=1, tor=1)
  wndName = whichPanel + "Window"; # the window name

Note: from Maya 2017 onwards, you need to duplicate default maya hotkey to be able to make changes, it is under Windows > Settings > Hotkey Editor

• reset hotkey

  cmds.hotkey(factorySettings=1)

• create hotkey

  import maya.cmds as cmds
  # cmds.hotkey(factorySettings=1)
  cmds.hotkey(autoSave=0)
   
  # -- toggle select mode
  g_shiToggleMode=0
  def toggleSelectMode(curMode):
      global g_shiToggleMode
      print([g_shiToggleMode, curMode])
      if g_shiToggleMode != curMode:
          if curMode == 1: 
              cmds.SelectVertexMask()
          elif curMode == 2:
              cmds.SelectEdgeMask()
          elif curMode == 3:
              cmds.SelectFacetMask()
          elif curMode == 0: 
              cmds.SelectToggleMode()
          g_shiToggleMode = curMode
      else:
          cmds.SelectToggleMode()
          g_shiToggleMode = 0
   
  for i in range(1,3+1):
      cmds.nameCommand('NC_shiToggleMode_'+str(i), ann='NC_shiToggleMode_'+str(i), c='python("toggleSelectMode({0})")'.format(i))
      cmds.hotkey(k=str(i), ctl=1, n='NC_shiToggleMode_'+str(i))
   
  # -- viewport
  cmds.nameCommand('NC_view_tWireframe', ann='NC_view_tWireframe', c='python("cmds.modelEditor(cmds.getPanel(up=1), e=1, wireframeOnShaded=(1-cmds.modelEditor(cmds.getPanel(up=1), q=1, wireframeOnShaded=1)))")')
  cmds.hotkey(k='f', ctl=1, alt=1, n='NC_view_tWireframe')
  # -- windows
  cmds.nameCommand('NC_win_outliner', ann='NC_win_outliner', c="OutlinerWindow;")
  cmds.hotkey(k='4', ctl=1, n='NC_win_outliner')
  # -- script editor
  cmds.nameCommand('NC_win_scriptEditor', ann='NC_win_scriptEditor', c="ScriptEditor")
  cmds.hotkey(k='x', ctl=1, alt=1, n='NC_win_scriptEditor')
  #-- hyperShade
  cmds.nameCommand('NC_win_hyperShade', ann='NC_win_hyperShade', c="HypershadeWindow")
  cmds.hotkey(k='s', ctl=1, alt=1, n='NC_win_hyperShade')
  #-- graph editor
  cmds.nameCommand('NC_win_graphEditor', ann='NC_win_graphEditor', c="GraphEditor")
  cmds.hotkey(k='g', ctl=1, alt=1, n='NC_win_graphEditor')
  #-- custom
  cmds.nameCommand('NC_fun01', ann='NC_fun01', c='python("fun01")')
  cmds.hotkey(k='d', ctl=1, alt=1, n='NC_fun01')

• Hotkey with Qt

  # ref: http://bindpose.com/custom-global-hotkey-maya/
  # qt import
  try:
      from PySide import QtGui, QtCore
      import PySide.QtGui as QtWidgets
      import shiboken
  except ImportError:
      try:
          from PySide2 import QtCore, QtGui, QtWidgets
          import shiboken2 as shiboken
      except ImportError:
          pass
  import maya.cmds as cmds
  import maya.OpenMayaUI as omui
  hotkey = {}
  mayaWindow = shiboken.wrapInstance(long(omui.MQtUtil.mainWindow()), QtWidgets.QWidget)
   
  def shortcut_process(keyname):
      if keyname == 'toggleWire':
          if 'modelPanel' in cmds.getPanel(wf=1):
              print('Done Something')
          else:
              # give key event to maya
              hotkey[keyname].setEnabled(0)
              e = QtGui.QKeyEvent(QtCore.QEvent.KeyPress, QtCore.Qt.Key_F, QtCore.Qt.ControlModifier | QtCore.Qt.AltModifier)
              QtCore.QCoreApplication.postEvent(mayaWindow , e)
              cmds.evalDeferred(partial(hotkey[keyname].setEnabled, 1))
      else:
          pass 
   
  # shortcut
  hotkey['toggleWire'] = QtWidgets.QShortcut(QtGui.QKeySequence('Ctrl+Alt+F'), mayaWindow)
  hotkey['toggleWire'].setContext(QtCore.Qt.ApplicationShortcut)
  hotkey['toggleWire'].activated.connect(partial(shortcut_process, 'toggleWire'))

Python Maya API reference

• Python script and Python Maya API example:
  • http://cgkit.sourceforge.net/maya_tutorials/intro/
• Cope with Python in Maya C++ API with MScriptUtil, for passing by reference; re-solved in API 2.0
  • http://www.chadvernon.com/blog/resources/maya-api-programming/mscriptutil/
• Maya API 2.0 for python, new python way of the redefined C++ API from Maya 2013
  • http://docs.autodesk.com/MAYAUL/2014/JPN/Maya-API-Documentation/python-api/index.html

common api page offical reference page

• all : http://download.autodesk.com/us/maya/2009help/api/classes.html

om.MDagPath:

• path info for Dag node, the normal way, python/mel refering to maya objects like Transform and Shape
• it is from the world node to a particular object in the DAG

• string name to MDagPath

  selectionList = om.MSelectionList()
  selectionList.add(mesh_name)
  mesh_dagPath = om.MDagPath()
  selectionList.getDagPath(0, mesh_dagPath)
  print(mesh_dagPath.partialPathName()) # if done correct, it will give same name as mesh_name

• MObject to MDagPath

  geo_obj.hasFn(om.MFn.kDagNode) # check if it is Dag node, then it can have a dag path
  geo_dagNode = om.MFnDagNode(geo_obj) # now it is a DagNode, then get DagPath from DagNode
  print( geo_dagNode.partialPathName() ) # since DagNode also has name function
  geo_dagPath = om.MDagPath()
  geo_dagNode.getPath(geo_dagPath)
  print( geo_dagPath.partialPathName() ) # proof geo_dagPath work correctly

• MFnDagNode to MDagPath()

  geo_dagPath = om.MDagPath()
  geo_dagNode.getPath(geo_dagPath)
  print( geo_dagPath.partialPathName() ) # proof geo_dagPath work correctly

om.MObject:

• MDagPath to MObject conversion,

  geo_transform_ojbect = geo_transform_dagPath.node()
  geo_transform_ojbect.hasFn(om.MFn.kTransform) # true, then can safely cast to MFnTransform

• string name to MObject conversion

  selectionList = om.MSelectionList()
  selectionList.add(skinName)
  skinClusterObj = om.MObject()
  selectionList.getDependNode(0,skinClusterObj)
  skinClusterObj.hasFn(om.MFn.kSkinClusterFilter) # use for testing become cast to the object function

MFnDagNode:

• take input Object and provide function to access object as DAG Node, for its attribute and modify
• it has same function as MDagPath like

  int = MDagPath.childCount() = MFnDagNode.childCount()
  MObject = MDagPath.child(index) = MFnDagNode.child(index)
  int = MDagPath.pathCount() = MFnDagNode.pathCount()
   
  # node only can return itself while path can return segment
  str = MDagPath.getPath(MDagPath, i) = MFnDagNode.getPath(MDagPath) 
   
  str = MDagPath.fullPathName() = MFnDagNode.fullPathName()
  str = MDagPath.partialPathName() = MFnDagNode.partialPathName()

• but MFnDagNode has ability to add and remove child, also duplicate, instanceCount
  • for its matric info, it has transformationMatrix()
• but MDagPath has ability to get nearby or itself for transform MObject, cast into shape MDagPath
  • for its matric info, it has inclusiveMatrix(), exclusiveMatrix(), inclusiveMatrixInverse(), exclusiveMatrixInverse()

• str to MFnDagNode

  selectionList = om.MSelectionList()
  selectionList.add(mesh_name)
  mesh_dagPath = om.MDagPath()
  selectionList.getDagPath(0, mesh_dagPath)
  mesh_dagNode = om.MFnDagNode(mesh_dagPath)

• MDagPath to MFnDagNode

  my_dagNode = om.MFnDagNode(my_dagPath)

• MObject to MFnDagNode

  my_obj.hasFn(om.MFn.kDagNode)
  my_dagNode = om.MFnDagNode(my_obj)

import maya.OpenMaya as om
selected = om.MSelectionList()
om.MGlobal.getActiveSelectionList(selected)
dagPath = om.MDagPath()
selected.getDagPath(0,dagPath)
print(dagPath.fullPathName()) # current full path name
print(dagPath.partialPathName()) # current node name
 
# get shape count
countUtil = om.MScriptUtil()
countUtil.createFromInt(0)
tmpIntPtr = countUtil.asUintPtr() # unsigned int
dagPath.numberOfShapesDirectlyBelow(tmpIntPtr)
print(countUtil.getUint(tmpIntPtr))
print(dagPath.childCount()) # another alternative method
 
# get its Shape as MDagPath
dagPath.extendToShape() # MDagPath: change to shape path, will error if has no shape or more than 1 shape
dagPath.extendToShapeDirectlyBelow(0) # same as above; but won't error when more than 1 shape
print(dagPath.fullPathName()) # shape, if already shape, also return itself
 
# get itself as Node
dagObj = dagPath.node() # MObject
dagObj.hasFn(om.MFn.kDagNode) # check if its DAG node, not DG node
dagNode = om.MFnDagNode(dagObj) # use function to handle this MObject
print(dagNode.fullPathName())
 
# get its Transform as Node
dagObj = dagPath.transform() # MObject: return its transform MObject, if already transform, it return itself
dagNode = om.MFnDagNode(dagObj)
print(dagNode.fullPathName()) # transform node full dag path

• MFnDependencyNode: it takes a MObject input to do creation and manipulation that dependency graph node, as some dependency node has no DAG path. but all DAG path pointing to a DAG node which is also DG node

  my_DGNode = OpenMaya.MFnDependencyNode(myObj)
  print(my_DGNode.name())

• MFnDependencyNode also has function like attribute editor, editing all the plug/attributes, and its related plugin info

• Conversion from other data
  • str name to MFnDependencyNode

    selectionList = OpenMaya.MSelectionList()
    selectionList.add(my_name)
    my_obj = OpenMaya.MObject()
    selectionList.getDependNode(0,my_obj)
    my_obj.hasFn(om.MFn.kDependencyNode) # check before convert
    my_dgNode = om.MFnDependencyNode(my_obj)

  • MDagPath to MFnDependencyNode

    my_obj = my_dagPath.node()
    my_obj.hasFn(om.MFn.kDependencyNode) # check before convert
    my_dgNode = om.MFnDependencyNode(my_obj)

  • MFnDagNode to MFnDependencyNode

    my_dagPath = my_dagNode.getPath()
    my_obj = my_dagPath.node()
    my_obj.hasFn(om.MFn.kDependencyNode) # check before convert
    my_dgNode = om.MFnDependencyNode(my_obj)

• MDGModifier: it act directly on adding nodes, making new connections, and removing existing connections in DG nodes

other common class:

• om.MPxNode: the the parent class for user defined dependency nodes.

ref: http://docs.autodesk.com/MAYAUL/2014/ENU/Maya-API-Documentation/index.html?url=cpp_ref/class_m_plug.html,topicNumber=cpp_ref_class_m_plug_html71ba8eb6-cc15-4382-8b6f-36cdfbc2ccc5

• MPlug is just API way of calling attribute.
• MPlug has network(built-in) and non-networked(user-created) ones
• MPlug can be a single attribute plug, or a array/element plug.
• MPlug can have its own MPlug, as compound plug, which can be accessed with .child(); the opposite is .parent()
• Array type MPlug can access its list of plug by .elementByLogicalIndex() and .elementByPhysicalIndex() method; the opposite is .array()

Array in MPlug:

• array are sparse.
• Logical Index used in MEL are sparse;
• Physical Index is not sparse, it range from 0-numElements()-1, while numElements may sometimes only reflect the amount of entry changed from default, thus sometimes, numElements is not equal to the total number of plug in array. MPlug[i] = MPlug.elementByPhysicalIndex(i)
• numElement only refer to data in datablock, to get update value, use

  my_arraPlugy.evaluateNumElements()
  print(my_arraPlugy.numElements())

Concept of Dynamic array - a pre-defined-size list with pre-loaded empty items

• as you can create array with any pre-defined size, Maya keep it in memory up to the size of last non-empty element; (ref: http://download.autodesk.com/global/docs/maya2014/en_us/index.html?url=files/Arrays_vectors_and_matrices_Get_and_change_the_size_of_an_array.htm,topicNumber=d30e790260)
• in addition, Maya is using the sparse array structure for array plugs(attributes)
  • Maya will automatically resize and create new list of elements for those item whose value is not zero.
  • thus the 2 methods in MPlug, where you can get plugs of the array by either logical index (sparse, means with zeros) or physical indexes (those with actual data connection).
  • ref: http://forums.cgsociety.org/archive/index.php?t-603088.html

• example MEL code

  string $nameArray[10];
  $nameArray[5]="objA"; // at place 5 in nameArray
  print("\n-------start sparse array--------\n");
  print $nameArray; // null null null null null objA
  print("-------end----------");
   
  $logical_index = stringArrayFind( "objA", 0, $nameArray ); // result: 5
  print("\nlogical index of 'objA': "+ $logical_index);
  print("\nsize: "+size($nameArray)); // size of array currently: 6
  print("\n9th: "+$nameArray[8]); // null
  print("\n11th: "+$nameArray[10]); // null
  print("\nsize: "+size($nameArray)); // size of array currently: 6
   
  string $nameArray_autoNonSparse_means_noEmpty[];
  for($each in $nameArray){
      if($each != ""){
          $cur_index = size($nameArray_autoNonSparse_means_noEmpty);
          $nameArray_autoNonSparse_means_noEmpty[$cur_index] = $each;
      }
  }
  print("\n-------start no sparse array--------\n");
  print($nameArray_autoNonSparse_means_noEmpty);
  print("-------end----------");
  $physical_index = stringArrayFind( "objA", 0, $nameArray_autoNonSparse_means_noEmpty ); // result: 0
  print("\nphysical index of 'objA': "+$physical_index+"\n");
   
  // clear from memory
  clear($nameArray);

  • so the logical index of a array is the number is in the [], and as like Python list and other language arrays
    • as shown in Maya skincluster joint list connection
      

The Physical index of joint in the influence list

• the most obvious demonstration of physical index of joint is in the component editor - skin weight tab
  
  • since “joint3” is deleted, and no longer has relationship in “skinCluster1”, thus there is no point put “joint3” column in the weight table;
  • the weight table is actual representation of the weight data;
    • including all the vertex
    • including all the joints linked to skinCluster, even it has 0 in weight
      • (make sure in component editor > option menu > Uncheck hide zero column)
      • (make sure in component editor > option menu > Uncheck sort alphabetically column)
      • 
  • and when saving, actual weight data store in a 1 dimension array { vtx[0][jnt1], vtx[0][jnt2] … vtx[7][jnt2] }
    • with joint name as column header, and vtx index as row header
    • so column index is the actual Physical index of joint used in referring weight data table
    • while the logical index of joint used in referring current connection flow.

• MScriptUtil ref: http://download.autodesk.com/us/maya/2011help/api/class_m_script_util.html
  • Input: createFrom*() Int, Double, List+len
  • middle: as*Ptr() # Int, Short, Float, Double, Uint, Bool, Char, Uchar, x2-4
  • output: get*() # Int, Short, Float, Double, Uint, Bool, Char, Uchar, x2-4
• code workflow

  py_var = 0 # your type, say Unsign Int
  util = om.MScriptUtil()
  util.createFromInt(py_var) # same as your type
  util_ptr = util.asUintPtr() # same as your type
  api_obj.api_function_return_a_value(util_ptr) # use pointer to hold the result value
  py_var = util.getUint(util_ptr) # same as your type
  print(py_var) # new value from API

• other align vector related reading (mel only)

  /*
  rot: rot vector around another vector by a degree
  rad_to_deg, deg_to_rad
  */

• MVector functions

  # ref: https://groups.google.com/forum/#!topic/python_inside_maya/-Yp8WfyTkPA
  # MVector: rotateBy (MVector::Axis axis, const double angle) 
  # get a MVector result by rotate one Vector around default x,y,z axis by certain degree
   
  # MVector: rotateBy (const MQuaternion &) const 
  # case 1: get a MVector result by rotate one Vector around another Vector by certain degree
  res_vector = mainVector.rotateBy( maya.OpenMaya.MQuaternion(math.radians(rotDegree), aimVector) )
  # case 2: get a MVector result by rotate one Vector by a swing motion defined by start vector to end vector
  res_vector = mainVector.rotateBy( maya.OpenMaya.MQuaternion(MotionStartVector, MotionEndVector, optionalPercentage ) )

• Align Object Axis one at a time to Vector direction (OpenMaya method)

  import maya.OpenMaya as om
  import math
  def getLocalVecToWorldSpaceAPI(obj, vec=om.MVector.xAxis):
      # ref: http://forums.cgsociety.org/showthread.php?t=1124527
      # take obj's local space vec to workspace, default object x axis
      selList = om.MSelectionList()
      selList.add(obj)
      nodeDagPath = om.MDagPath()
      selList.getDagPath(0, nodeDagPath)
      matrix = nodeDagPath.inclusiveMatrix()
      vec = (vec * matrix).normal()
      return vec.x, vec.y, vec.z
   
  # define objects
   
  # a locator reference that we are aligning our pCube object to
  # of course, you dont need a refLoc, you can use Vector from other data as well
  # here locator is just a visual example
  refLoc = 'locator_1'
  obj = 'pCube1' # a cube we are aligning
   
  # grab object transform function lib
  selectionList = om.MSelectionList()
  selectionList.add( obj )
  dagPath = om.MDagPath()
  selectionList.getDagPath(0, dagPath)
  fnTransform = om.MFnTransform(dagPath)
   
  # STEP 1: align Y axis first
  refLoc_normal_y = getLocalVecToWorldSpaceAPI(refLoc, om.MVector.yAxis)
  aim_vec_y = om.MVector(*refLoc_normal_y) # break array into 3 parameters
  obj_normal_y = getLocalVecToWorldSpaceAPI(obj, om.MVector.yAxis)
  obj_vec_y = om.MVector(*obj_normal_y)
  rot_quaternion = obj_vec_y.rotateTo(aim_vec_y)
  # absolute version
  #fnTransform.setRotationQuaternion( rot_quaternion.x, rot_quaternion.y, rot_quaternion.z, rot_quaternion.w ) 
  # relative transform on top of existing obj transform
  fnTransform.rotateBy(rot_quaternion)
   
  # STEP 2: align Z axis
  refLoc_normal_z = getLocalVecToWorldSpaceAPI(refLoc, om.MVector.zAxis)
  aim_vec_z = om.MVector(*refLoc_normal_z)
  obj_normal_z = getLocalVecToWorldSpaceAPI(obj, om.MVector.zAxis)
  obj_vec_z = om.MVector(*obj_normal_z)
  rot_quaternion = obj_vec_z.rotateTo(aim_vec_z)
  fnTransform.rotateBy(rot_quaternion)

• get position

  #general
  pos = cmds.xform(obj, q=1, t=1, ws=1)
   
  # loc
  pos = cmds.getAttr(loc+'.worldPosition')[0] # world position
  pos = cmds.pointPosition(loc) # world position
   
   
  #cv - local position from origin at creation time
  cmds.getAttr('my_curve.cv[1]')[0]
  cmds.pointPosition('my_curve.cv[1]',l=1)
   
  # vtx -
  cmds.getAttr('pCube1.vtx[1]')[0] # local offset value since creation
  cmds.getAttr("pCube1.pnts[1]")[0] # local offset value since creation
   
  cmds.pointPosition('pCube1.vtx[0]',l=1)
  cmds.setAttr("pCubeShape1.pnts[5].pntx", 0)
  cmds.setAttr("pCubeShape1.pnts[5].pnty", 0)
  cmds.setAttr("pCubeShape1.pnts[5].pntz", 0)
   
  # vtx - local position relative to pivot
   
  # loc, vtx, cv, uv, point - global position
  pos = cmds.pointPosition(pointObj)

• freeze transform
  • it will make curve like re-created based on current result shape, previous local cv position is same as global position
  • it will make polygon pivot change back to origin, and vtx global position stay same, local position will same as current global position, and its offset value will be based on previous value
  • code

    cmds.makeIdentity(cmds.ls(sl=1),apply=1,t=1,r=1,s=1,n=0)

• get current selection

  selected = om.MSelectionList()
  om.MGlobal.getActiveSelectionList(selected)

• get current soft selection and weight

  def getVtxSelectionSoft_OpenMaya():
      # ref: http://around-the-corner.typepad.com/adn/2013/05/support-soft-selection-with-custom-mpxcomponentshape.html
      startTime = cmds.timerX() # 0.13s > no string 0.07s
      # soft selection
      softSelectionList = om.MSelectionList()
      softSelection = om.MRichSelection()
      om.MGlobal.getRichSelection(softSelection)
      softSelection.getSelection(selectionList)
   
      selectionPath = om.MDagPath()
      selectionObj = om.MObject()
      iter = om.MItSelectionList( selectionList, om.MFn.kMeshVertComponent)
      #elements = []
      id_list = []
      weights = []
      node_list = []
      while not iter.isDone():
          iter.getDagPath( selectionPath, selectionObj )
          selectionPath.pop() #Grab the parent of the shape node
          node = selectionPath.fullPathName()
          compFn = om.MFnSingleIndexedComponent(selectionObj)   
          getWeight = lambda i: compFn.weight(i).influence() if compFn.hasWeights() else 1.0
          node_list.append(node)
          for i in range(compFn.elementCount()):
              #elements.append('{0}.vtx[{1}]'.format(node, compFn.element(i)))
              id_list.append(compFn.element(i))
              weights.append(getWeight(i)) 
          iter.next()
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
      return list(set(node_list)), id_list, weights

• API way to get selection vertex ids (single geo case), and set selection using vertex ids

  def createVtxSelection_cmds(objName, id_list):
      startTime = cmds.timerX() # 0.039s
      result_sel = ['{0}.vtx[{1}]'.format(objName, i) for i in id_list]
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
      return result_sel
   
  def createVtxSelection_OpenMaya(objName, id_list):
      # ref: http://discourse.techart.online/t/maya-api-components/3400/3
      startTime = cmds.timerX() # 0.009s
      sel = om.MSelectionList()
      sel.add(objName)
      mdag = om.MDagPath()
      sel.getDagPath(0, mdag)
      util = om.MScriptUtil()
      util.createFromList(id_list, len(id_list))
      ids_ptr = util.asIntPtr()
      ids = om.MIntArray(ids_ptr, len(id_list))
   
      compFn = om.MFnSingleIndexedComponent()
      components = compFn.create( om.MFn.kMeshVertComponent )
      compFn.addElements(ids)
   
      result_sel = om.MSelectionList()
      result_sel.add(mdag, components)
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
      return result_sel
   
  def getVtxSelection_cmd(l=0):
      startTime = cmds.timerX() # 0.18s
      selected = cmds.ls(sl=1, fl=1, l=l) # len(selected)
      id_list = [x.split('[',1)[-1][:-1] for x in selected]
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
      return selected[0].split['.'][0], id_list
   
  def getVtxSelection_OpenMaya():
      startTime = cmds.timerX() # 0.11s > no comp iter: 0.039
      # normal selection
      normalSelectionList = om.MSelectionList()
      om.MGlobal.getActiveSelectionList(normalSelectionList)
      selectionPath = om.MDagPath()
      selectionObj = om.MObject()
      indexList = om.MIntArray()
      iter = om.MItSelectionList( normalSelectionList, om.MFn.kMeshVertComponent )
      #normalSelectionElements = [] # len(normalSelectionElements)
      node_list = []
      id_list = []
      while not iter.isDone():
          iter.getDagPath( selectionPath, selectionObj )
          selectionPath.pop()
          node = selectionPath.fullPathName()
          compFn = om.MFnSingleIndexedComponent(selectionObj) # flatten the component selection
          compFn.getElements(indexList)
          id_list.extend(list(indexList))
          node_list.append(node)
          '''
          for i in range(compFn.elementCount()):
              normalSelectionElements.append('{0}.vtx[{1}]'.format(node, compFn.element(i)))
              id_list.append(compFn.element(i))
          '''
          iter.next()
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
      return list(set(node_list)), id_list

• list of cmds in both python and mel for modeling

# mel: DeleteHistory;
cmds.DeleteHistory()
 
# show poly vertex
# mel: setPolygonDisplaySettings("verts");
cmds.polyOptions(r=1, activeObjects=1, dv=1)
 
# mel: ToggleFaceNormalDisplay;
cmds.ToggleFaceNormalDisplay()
 
# mel: ToggleBackfaceGeometry;
cmds.ToggleBackfaceGeometry()
 
# mel: ReversePolygonNormals;
cmds.ReversePolygonNormals()
 
# hard edge
# mel: SoftPolyEdgeElements(0);
cmds.polySoftEdge(a=0)
 
# show border
# mel: ToggleBorderEdges;
cmds.ToggleBorderEdges()
 
# dialog to change edge width display
# mel: ChangeEdgeWidth;
cmds.ChangeEdgeWidth()
 
# show UV window
# mel: TextureViewWindow;
cmds.TextureViewWindow();
# mel: CenterPivot;
cmds.CenterPivot()
 
# turn on / off symmetric modeling
'''
symmetricModelling -e -symmetry true;symmetricModelling -e -symmetry false;
symmetricModelling -e -about "world";
symmetricModelling -e -about "object";
symmetricModelling -e -axis "x"
'''
cmds.symmetricModelling(e=1, symmetry=1)
cmds.symmetricModelling(e=1, symmetry=0)
 
# face selection to edge border selection
# mel: select -r `polyListComponentConversion -ff -te -bo`;
cmds.select(cmds.polyListComponentConversion(ff=1, te=1, bo=1),r=1)
 
# selection to shell
# mel: ConvertSelectionToShell;
cmds.ConvertSelectionToShell()
 
# selection to create layer
'''
string $tmpname[]=`ls -sl`;
createDisplayLayer -name ($tmpname[0]+"_Lyr") -number 1 -nr;
'''
selected = cmds.ls(sl=1)
if len(selected)>0:
    cmds.createDisplayLayer(name=selected[0]+'_layer', number=1, nr=1)
 
# remove from layers
# mel: editDisplayLayerMembers -noRecurse "defaultLayer" `ls -sl`
cmds.editDisplayLayerMembers("defaultLayer", cmds.ls(sl=1), noRecurse=1)
 
 
#### curve #####
 
# show CV
# mel: ToggleCVs;
cmds.ToggleCVs()
 
# show editable point
# mel: ToggleEditPoints;
cmds.ToggleEditPoints()
 
# rebuild curve dialog
# mel: RebuildCurveOptions;
cmds.RebuildCurveOptions()
 
# detach surface by edge or isopam
# mel: DetachCurve;
cmds.DetachCurve()
 
# detach/attach curve by cut
# mel: CutCurve; AttachCurve;
cmds.CutCurve()
cmds.AttachCurve()

Vertex check in API way

• poly count

  vtx_cnt = cmds.polyEvaluate(geoName, v=1)

• get transform to shape to vtx

  selected = om.MSelectionList()
  om.MGlobal.getActiveSelectionList(selected)
   
  dagPath = om.MDagPath()
  selected.getDagPath(0,dagPath)
   
  print(dagPath.fullPathName()) # transform
  dagPath.extendToShape() # .extendToShapeDirectlyBelow() if dont want to get child of child; will error if has no shape
  print(dagPath.fullPathName()) # shape, if shape, also return itself
   
  dagPath.transform() # transform
   
  mesh = om.MFnMesh(dagPath.node()) # MObject to MeshFunction
  print(mesh.numVertices()) # vtx count

Vertex Check

• test empty geo shape

  # test empty geo shape
  all_geo_list = cmds.ls(type='mesh')
  zeroVtx_list = []
  for each in all_geo_list:
      if cmds.polyEvaluate(each, v=1) == 0:
          zeroVtx_list.append(each)
  print(zeroVtx_list)

Face Check and Correct

• double side face

  shape_list = cmds.ls(type='mesh')    
  for shape in shape_list:
      cmds.setAttr(shape+".doubleSided", 1)

Curve related

• get curve construction info

  def getCurveInfo(curveObj, index=2):
      d = cmds.getAttr(curveObj+'.degree')
      p = cmds.getAttr(curveObj+'.cv[:]')
      p_new = [ [numClean(y, index) for y in x] for x in p]
      tmpInfo = cmds.createNode( 'curveInfo' )
      cmds.connectAttr( curveObj + '.worldSpace', tmpInfo+'.inputCurve' )
      k = cmds.getAttr( tmpInfo + '.knots[*]' )
      cmds.delete(tmpInfo)
      return (d, p_new, k)
   
  def numClean(fnum, index=2):
      rule = "{0:."+str(index)+"f}"
      cnum = float(rule.format(fnum))
      if cnum.is_integer():
          cnum = int(cnum)
      return cnum
   
  def setCurveInfo(curveObj, curveInfo):
      # input: dict - d, p; p ; d,p,k
      if not isinstance(curveInfo, dict) or 'p' not in curveInfo.keys():
          print('require curveInfo in dict of d,p,k or d,p or p')
          return
      if all(x in curveInfo.keys() for x in ['d','p','k']):
          return cmds.curve(curveObj,r=1,d=curveInfo['d'], p=curveInfo['p'], k=curveInfo['k'])
      elif all(x in curveInfo.keys() for x in ['d','p']):
          return cmds.curve(curveObj,r=1,d=curveInfo['d'], p=curveInfo['p'])
      else:
          return cmds.curve(curveObj,r=1,d=1, p=curveInfo['p'])
   
  def buildCurveInfo(curveInfo, n='tmpCurve'):
      # input: dict - d, p; p ; d,p,k
      if not isinstance(curveInfo, dict) or 'p' not in curveInfo.keys():
          print('require curveInfo in dict of d,p,k or d,p or p')
          return
      if all(x in curveInfo.keys() for x in ['d','p','k']):
          return cmds.curve(n=n,d=curveInfo['d'], p=curveInfo['p'], k=curveInfo['k'])
      elif all(x in curveInfo.keys() for x in ['d','p']):
          return cmds.curve(n=n,d=curveInfo['d'], p=curveInfo['p'])
      else:
          return cmds.curve(n=n,d=1, p=curveInfo['p'])

• curve_mel2py cmd convertor

  #txt = 'curve -d 1 -p 0 0 1 -p 0 0.5 0.866025 -p 0 0.866025 0.5 -p 0 1 0 -p 0 0.866025 -0.5 -p 0 0.5 -0.866025 -p 0 0 -1 -p 0 -0.5 -0.866025 -p 0 -0.866025 -0.5 -p 0 -1 0 -p 0 -0.866025 0.5 -p 0 -0.5 0.866025 -p 0 0 1 -p 0.707107 0 0.707107 -p 1 0 0 -p 0.707107 0 -0.707107 -p 0 0 -1 -p -0.707107 0 -0.707107 -p -1 0 0 -p -0.866025 0.5 0 -p -0.5 0.866025 0 -p 0 1 0 -p 0.5 0.866025 0 -p 0.866025 0.5 0 -p 1 0 0 -p 0.866025 -0.5 0 -p 0.5 -0.866025 0 -p 0 -1 0 -p -0.5 -0.866025 0 -p -0.866025 -0.5 0 -p -1 0 0 -p -0.707107 0 0.707107 -p 0 0 1 -k 0 -k 1 -k 2 -k 3 -k 4 -k 5 -k 6 -k 7 -k 8 -k 9 -k 10 -k 11 -k 12 -k 13 -k 14 -k 15 -k 16 -k 17 -k 18 -k 19 -k 20 -k 21 -k 22 -k 23 -k 24 -k 25 -k 26 -k 27 -k 28 -k 29 -k 30 -k 31 -k 32'
   
  # maya float number cleaner
  def numClean(fnum, index=2):
      rule = "{0:."+str(index)+"f}"
      cnum = float(rule.format(fnum))
      if cnum.is_integer():
          cnum = int(cnum)
      return cnum
   
  def curve_mel2py(txt):
       rest, k = txt.split('-k',1)
       ks = [int(x.strip()) for x in k.split('-k')]
       rest, p = rest.split('-p',1)
       ps = [ x.strip().split() for x in p.split('-p') ]
       ps = [ [numClean(float(y)) for y in x] for x in ps]
       d = int(rest.split('-d',1)[-1].strip())
       result = "created = cmds.curve(d={0}, p={1}, k={2})".format(d, str(ps), str(ks))
       return result

• create NurbsCurve passing defined point list

  lineCurve = cmds.curve(p=pointList, d=1)
  nurbsCurve = cmds.fitBspline(lineCurve,ch=0,tol=0.01)
  cmds.delete(lineCurve)

• Research on API vs Cmds in Get and Set Vertex Position based on optional selection

  # ref: http://www.fevrierdorian.com/blog/post/2011/09/27/Quickly-retrieve-vertex-positions-of-a-Maya-mesh-(English-Translation)
  def getVtxSelection_OpenMaya():
      startTime = cmds.timerX() # 0.11s > no comp iter: 0.039
      # normal selection
      normalSelectionList = om.MSelectionList()
      om.MGlobal.getActiveSelectionList(normalSelectionList)
      selectionPath = om.MDagPath()
      selectionObj = om.MObject()
      indexList = om.MIntArray()
      iter = om.MItSelectionList( normalSelectionList, om.MFn.kMeshVertComponent )
      #normalSelectionElements = [] # len(normalSelectionElements)
      node_list = []
      id_list = []
      while not iter.isDone():
          iter.getDagPath( selectionPath, selectionObj )
          selectionPath.pop()
          node = selectionPath.fullPathName()
          compFn = om.MFnSingleIndexedComponent(selectionObj) # flatten the component selection
          compFn.getElements(indexList)
          id_list.extend(list(indexList))
          node_list.append(node)
          '''
          for i in range(compFn.elementCount()):
              normalSelectionElements.append('{0}.vtx[{1}]'.format(node, compFn.element(i)))
              id_list.append(compFn.element(i))
          '''
          iter.next()
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
      return list(set(node_list)), id_list
   
  def getVtxPos_cmd( shapeNode, sl=0 ):
      # full path, duplicate name proof
      startTime = cmds.timerX()
      pos_list = []
      index_list = []
      if sl==0: # 0.885
          #index_list = cmds.getAttr( shapeNode+".vrts", multiIndices=True ) # 0.0089
          index_list = range( cmds.polyEvaluate(shapeNode,v=1) ) # 0.007
      else: # 0.244
          shapeNode, index_list = getVtxSelection_OpenMaya() # 0.01
          shapeNode = shapeNode[0] 
      for i in index_list: #i=0
          pos = cmds.xform( '{0}.vtx[{1}]'.format(shapeNode, i), q=1, t=1, ws=1)
          pos_list.append( pos )
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
      return index_list, pos_list
  def setVtxPos_cmd( shapeNode, pos_data, sl=0 ):
      startTime = cmds.timerX()
      cmds.undoInfo(openChunk=1)
      index_list, pos_list = pos_data
      if sl== 0: # 4.38
          for i in range(len(index_list)):
              cmds.xform('{0}.vtx[{1}]'.format(shapeNode, index_list[i]), t=pos_list[i], ws=1)
      else: # 5.29
          sel_index_list = getVtxSelection_OpenMaya()[1]
          if not set(sel_index_list).issubset(set(index_list)):
              print('selection is not subset of stored plmp data.')
              return
          for id in sel_index_list:
              i = index_list.index(id)
              cmds.xform('{0}.vtx[{1}]'.format(shapeNode, id), t=pos_list[i], ws=1)
      cmds.undoInfo(closeChunk=1)
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
   
  def getVtxPos_OpenMaya( shapeNode, sl=0 ):
      # full path, duplicate name proof
      startTime = cmds.timerX() 
      pos_list = []
      index_list = []
      if sl==0: # 0.18
          selectionList = om.MSelectionList()
          selectionList.add(shapeNode)
          dagPath = om.MDagPath()
          selectionList.getDagPath(0, dagPath)
   
          mesh_fn = om.MFnMesh(dagPath)
          meshPointArray = om.MPointArray()
          mesh_fn.getPoints(meshPointArray, om.MSpace.kWorld)
          index_list = range(meshPointArray.length())
          for i in index_list:
              pos_list.append( [meshPointArray[i][0], meshPointArray[i][1], meshPointArray[i][2]] )
      else: # 0.04
          selectionList = om.MSelectionList()
          om.MGlobal.getActiveSelectionList(selectionList)
          selectionPath = om.MDagPath()
          selectionCompObj = om.MObject()
          iter_sel = om.MItSelectionList( selectionList, om.MFn.kMeshVertComponent )    
          while not iter_sel.isDone():
              iter_sel.getDagPath( selectionPath, selectionCompObj )
              iter_vtx = om.MItMeshVertex(selectionPath,selectionCompObj)
              while not iter_vtx.isDone():
                  pnt = iter_vtx.position(om.MSpace.kWorld)
                  index_list.append( iter_vtx.index() )
                  pos_list.append([pnt.x, pnt.y, pnt.z])
                  iter_vtx.next()
              iter_sel.next()
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))
      return index_list, pos_list
   
  def setVtxPos_OpenMaya(shapeNode, pos_data, sl=0):
      startTime = cmds.timerX()
      cmds.undoInfo(openChunk=1)
      index_list, pos_list = pos_data
      selectionList = om.MSelectionList()
      selectionList.add(shapeNode)
      dagPath = om.MDagPath()
      selectionList.getDagPath(0, dagPath)
      mesh_fn = om.MFnMesh(dagPath)
      if sl==0: # 0.069
          # set one by one - 4.22
          #for i in range(len(index_list)):
          #    mesh_fn.setPoint(index_list[i], om.MPoint(*pos_list[i]) )
          # get all and get all - 0.069
          meshPointArray = om.MPointArray()
          mesh_fn.getPoints(meshPointArray, om.MSpace.kWorld)
          for i in range(len(index_list)):
              meshPointArray.set(index_list[i],*pos_list[i] )
          mesh_fn.setPoints(meshPointArray, om.MSpace.kWorld)
      else: # 0.53
          sel_index_list = getVtxSelection_OpenMaya()[1]
          if not set(sel_index_list).issubset(set(index_list)):
              print('selection is not subset of stored plmp data.')
              return
          meshPointArray = om.MPointArray()
          mesh_fn.getPoints(meshPointArray, om.MSpace.kWorld)
          for id in sel_index_list:
              i = index_list.index(id)
              meshPointArray.set(id,*pos_list[i] )
          mesh_fn.setPoints(meshPointArray, om.MSpace.kWorld)
      cmds.undoInfo(closeChunk=1)
      totalTime = cmds.timerX(startTime=startTime)
      print("\nTotal Time: {0}".format(totalTime))

• assign material to selection or objects

  cmds.hyperShade(testGeo, assign='refMat')

• material creation

  cmds.shadingNode('lambert', n='refMat', asShader=1)

• change property

  cmds.setAttr('{0}.transparency'.format(testMat), 0.5, 0.5, 0.5, type="double3")

• delete unknown nodes, but check “exists”, “not referenced”, “not locked”

  nodeList = cmds.ls(type=['unknown', 'unknownDag', 'unknownTransform'])
  #nodeToDelete  = nodeList[0]
  def deleteIfNotReferenced( nodeList ):
      if not isinstance(nodeList, (list, tuple)):
          nodeList = [nodeList]
      for nodeToDelete in nodeList:
          if cmds.objExists(nodeToDelete) and not cmds.reference(nodeToDelete, q=1, isNodeReferenced=1):
              isLocked = cmds.lockNode(nodeToDelete, q=1, lock=1)[0]
              if not isLocked:
                  cmds.delete( nodeToDelete )

• remove prefix in shape and transform and avoid same node name level collision
• python

  mesh_list = cmds.ls('sw2_*',type='mesh',l=1)
  for each_mesh in mesh_list:
      info = each_mesh.rsplit('|',1)
      if len(info )==2:
          cmds.rename(each_mesh, info[-1].replace('sw2_',''))
      else:
          print(each_mesh)
   
  obj_list = cmds.ls('sw2_*',type='transform',l=1)
  for each_obj in obj_list:
      info = each_obj.rsplit('|',1)
      if len(info)==2:
          cmds.rename(each_obj, info[-1].replace('sw2_',''))
      else:
          print(each_obj)

• for blendshape and constraints, there is always an alias name for the weight Attribute, code example

  alias_target_weight_list = cmds.aliasAttr( final_bs, q=1 ) # ['body_BST', 'weight[0]']
  target_list = alias_target_weight_list[::2] # all the alias target names
  weight_attr_list = alias_target_weight_list[1::2] # all the weight attribute list

• graphic:python:maya:research_maya_weight_api: The Complete Research and Study on Maya Weight in Mel Python and C++ API

• apply single vtx weight to whole geo, good for unify same weight on attachment type geos on another surface

  attach_vtx_id = 16 # use same weight as on vtx[16]
  cur_skin = cmds.skinCluster(cur_bones, cur_geo, tsb=1, n=cur_geo+'_skinCluster')[0]
  cmds.setAttr( cur_skin + ".skinningMethod", 1)
  vtx_weight = cmds.skinPercent(cur_skin, cur_geo+'.vtx[{0}]'.format(attach_vtx_id), q=1, v=1)
  cmds.skinPercent(cur_skin, cur_geo+'.vtx[:]', tv=zip(cur_bones,vtx_weight))

• get only bone affecting the selected vtx

  cur_vtx_list = cmds.ls(sl=1, fl=1)
  if len(cur_vtx_list)>0:
      if '.vtx[' in cur_vtx_list[0]:
          cur_skin = weightAPI.findRelatedSkinCluster( cur_vtx_list[0].split('.')[0] )
          affect_boneList = cmds.skinPercent(cur_skin, cur_vtx_list, q=1, ignoreBelow=0.01, t=None)

• select only vtx affected the defined bone

  cmds.skinCluster(cur_skin, e=1, selectInfluenceVerts=bone_name)

• each vertex of a polygon model holds local transform value at [0,0,0], but after some move and sculpt, the vertex local position value changed,
• you can optionally clear out local vertex transform with cmds.polyMoveVertex(localTranslate=(0, 0, 0)), and delete history
• however, Blendshape in maya seems not care about those local transform or global transform, it only care its position relative to origin when object is at zero x,y,z transform in channel box
• move at object level will not affect blendshape unless you tell blendshape to look at global level instead of vertex level
• also, any deform modifier added on the object will reset all the vertex local value to 0,0,0 in result object shape.
• inputTarget[0].paintTargetWeights[11]: this is just a temporary weight holder, as anytime you use blendshape paint tool to select which data to paint on, it loads the data into this attribute.

• vtx general info code

  cmds.getAttr('ball.vtx[0]')[0] # those value in channelbox CV, and component editor
   
  cmds.polyMoveVertex(localTranslate=(0, 0, 0)) # clear local values

• blendshape per target per vtx weight info cmds way

  cmds.getAttr(cur_bs+'.it[0].itg[0].tw[0]') # cmds method extremely slow even for a ball
   
  # target 1 : weight per vtx
  cmds.getAttr('blendShape1.inputTarget[0].inputTargetGroup[0].targetWeights[240]')
  cmds.getAttr('blendShape1.inputTarget[0].inputTargetGroup[0].targetWeights')[0] # get full list of weights
  # target 2 : weight per vtx
  cmds.getAttr('blendShape1.inputTarget[0].inputTargetGroup[1].targetWeights[240]')
   
  # set target 2: weight per vtx
  cmds.setAttr('blendShape1.inputTarget[0].inputTargetGroup[1].targetWeights[241]', .8)
   
  # get current loaded paint weight data
  cmds.getAttr(cur_bs+'.it[0].pwt[11]') #vtx 11 at current paint data
   
  # get current base (the final mixing global per vtx weight)
  cmds.getAttr(cur_bs+'.it[0].bw[11]') #vtx 11 at current paint data

• API: MFnBlendShapeDeformer

  import maya.OpenMaya as om
  import maya.OpenMayaAnim as oma
  selectionList = om.MSelectionList()
  selectionList.add(cur_bs)
  bs_obj = om.MObject()
  selectionList.getDependNode(0,bs_obj)
  bs_obj.hasFn(om.MFn.kBlendShape)
  bs_fn = oma.MFnBlendShapeDeformer(bs_obj) # blendshape object fn
  # current result object
  obj_list = om.MObjectArray()
  bs_fn.getBaseObjects(obj_list)
  print(obj_list.length()) # 1, only one blendshape object, even if it has more targets
  bs_base_obj = obj_list[0]

• API: weight slider attribute and alias target attribute name

  nWeights = bs_fn.numWeights() # number of blend targets
  indexList = om.MIntArray() 
  # get logic index of blend targets, since target can be remove from array, and become sparse
  bs_fn.weightIndexList(indexList)
   
  w_info_list=[] # weight attr info
  w_plug = bs_fn.findPlug('weight')
  for index in indexList:
      cur_plug = w_plug.elementByLogicalIndex(index)
      cur_plug_alias = bs_fn.plugsAlias(cur_plug)
      cur_plug_w = bs_fn.weight(index)
      w_info_list.append([cur_plug_alias, cur_plug_w])
  print(w_info_list)

• API: baseWeights data (overall deform weight map):

  inputTargetArrayPlug = bs_fn.findPlug('inputTarget')
  inputTargetPlug = inputTargetArrayPlug.elementByLogicalIndex(0)  # base_model
  # base weight list
  baseWeightsArrayPlug = inputTargetPlug.child(1) # .inputTarget[0].baseWeights
  vtxCnt = cmds.polyEvaluate(base_geo,v=1)
  base_weight_list = [1]*vtxCnt # default is 1
   
  for j in range(baseWeightsArrayPlug.numElements()):
      cur_plug = baseWeightsArrayPlug.elementByPhysicalIndex(j) # same as baseWeightsArrayPlug[j]
      logicalIndex = cur_plug.logicalIndex()
      base_weight_list[logicalIndex] = cur_plug.asFloat() # update from sparse array data
   
  # following method may fail if you start maya fresh and read the scene 
  '''
  base_weight_list = []
  for j in range(baseWeightsArrayPlug.numElements()): # fresh start will cause numElements become 0 or sparse count again, since not in datablock memory yet
      base_weight_list.append( baseWeightsArrayPlug.elementByLogicalIndex(j).asFloat() )
  '''
  # even this will not get the full index list
  baseWeightsArrayPlug.evaluateNumElements()
  print(baseWeightsArrayPlug.numElements())

• API: targetWeights data for each target

  inputTargetGroupArrayPlug = inputTargetPlug.child(0)
   
  target_weight_data = []
  for index in indexList: # i=0
      inputTargetGroupPlug = inputTargetGroupArrayPlug.elementByLogicalIndex(index) # inputTargetGroupPlug.name()
      targetWeightsArrayPlug = inputTargetGroupPlug.child(1) # .targetWeights
      target_weight_list = [1]*vtxCnt 
      for j in range(targetWeightsArrayPlug.numElements()): # j=0
          cur_plug = targetWeightsArrayPlug.elementByPhysicalIndex(j)
          logicalIndex = cur_plug.logicalIndex()
          target_weight_list[logicalIndex] = cur_plug.asFloat()
      target_weight_data.append(target_weight_list)

* API: Geometry result deformed vertex list position info

pos_list = []
geo_iter = om.MItGeometry(obj_list[0])
while not geo_iter.isDone():
    p = geo_iter.position()
    pos_list.append((p.x, p.y, p.z))
    geo_iter.next()

• API: Data of Target shape vertex list position info

  target_data = []
   
  def geoObject_to_posList_OpenMaya(geo_object):
      # MObject as input
      geo_iter = om.MItGeometry(geo_object)
      pos_list = []
      while not geo_iter.isDone():
          pnt = geo_iter.position()
          pos_list.append([pnt.x, pnt.y, pnt.z])
          geo_iter.next()
      return pos_list
   
  for index in indexList: # i = 0
      target_object_data = []
   
      target_list = om.MObjectArray()
      bs_fn.getTargets(bs_base_obj, index, target_list)
      # target_list.length() #1, ideally one blend target only have one object
      target_cnt = target_list.length()
      if target_cnt > 1:
          # more than one object case
          for j in range(target_cnt ):
              target_object_data.append( geoObject_to_posList_OpenMaya(target_list[j]) )
      else:            
          # normal one object case
          if target_cnt == 0:
              # no longer object link to it, get it from base
              # switch all shape off and only leave it on
              old_w_list = []
              for n in indexList:
                  old_w_list.append( [ n, bs_fn.weight(n) ] ) # backup
                  bs_fn.setWeight(n, 0)
              bs_fn.setWeight(n, 1)
              # get object data
              target_object_data.append( geoObject_to_posList_OpenMaya(bs_base_obj) )
              # from backup
              for n, w in old_w_list:
                  bs_fn.setWeight(n, w)
          elif target_cnt == 1:
              target_object_data.append( geoObject_to_posList_OpenMaya(target_list[0]) )
      # - 
      target_data.append(target_object_data)
   
  # locator creation
  def pos_to_loc(pos_list, prefix='tmp'):
      for i,pos in enumerate(pos_list):
          cur_loc = cmds.spaceLocator(n='loc_{0}_{1}'.format(prefix,i))[0]
          cmds.xform(cur_loc, t=pos)
   
  for i,targets in enumerate(target_data):
      pos_to_loc(targets[0], 'tgt'+str(i))

Import and Export animation with atom plugin

• import

  # select controls to load animation, then
  cmds.file("D:/path_to_file/pose_001.atom", i=1, type="atomImport")

Import and Export animation with Maya built-in file import export

• method 1: select the animation curve nodes, then just export those nodes for later import and manual reconnect

  cmds.file("D:/path_to_scene/animation_node_only_v001.ma", f=1, typ="mayaAscii", es=1) 

  • the result file will contains, animation nodes + renderGlobals stufs
• method 2: select animated objects, then just export animation info with auto reconnect on import

  cmds.file("D:/path_to_scene/animation_node_only_v002.ma", f=1, typ="mayaAscii", exportSelectedAnim=1) 

  • the result file will contains, animation nodes + re-connection commands, you can replace namespace on import back with -swapNamespace, but you can't change object of re-connection info, so not flexible, better with first method and do dictionary data connection

Get all Animation Curve

• note: it may include time value driven drive key curve, so need check

  for animCurve_type in ['animCurveTA', 'animCurveTL', 'animCurveTU']:
      curve_list = cmds.ls( type = animCurve_type )
   
      for each_curve in curve_list:
          cur_connection_out = each_curve + ".output"
          destinations = cmds.connectionInfo(cur_connection_out, destinationFromSource=1)
          if len(destinations) == 0:
              # optional process for unconnected animation node
              cmds.delete(each_curve)
          else:
              cur_node_attr = destinations[0]
              cur_node, cur_attr = cur_node_attr.split('.')
              # optional get transform node
              cur_transform = ''
              if cmds.nodeType(cur_node) == 'transform':
                  cur_transform = cur_node
              else:
                  try_parent = cmds.listRelatives(cur_node, p=1)
                  if try_parent:
                      cur_transform = cmds.listRelatives(cur_node, p=1)[0]
              # optional unlock attribute
              old_lock = cmds.getAttr(cur_node_attr, l=1)
              cmds.setAttr(cur_node_attr, l=0)
              # optional process here
              cmds.delete(cur_node_attr, staticChannels=1, unitlessAnimationCurves=0, hierarchy="", controlPoints=0, shape=1)
              # lock back
              cmds.setAttr(cur_node_attr, lock= old_lock)

Clean Static Animation on object

• note: that operation can't take locked channel, so unlock process may required
• general clean static animation

  cmds.delete(cur_node_attr, staticChannels=1, unitlessAnimationCurves=0, hierarchy="", controlPoints=0, shape=1)

Bake Animation

• note: make sure all channel unlocked
• bake animation curve

  cmds.bakeResults(animation_curve_node,t=(bake_start,bake_end))

• bake object

  cmds.bakeResults(object_node,t=(bake_start,bake_end))

• check abc node inside maya, and its cache path

  # get all abc node
  all_abc_nodes = cmds.ls(type='AlembicNode')
  # check current file path
  for each in all_abc_nodes:
      print('------------------')
      print('For node: {0}'.format(each))
      print(cmds.getAttr(each+'.fn'))
      print(cmds.getAttr(each+'.fns'))

• to update abc cache path, (default maya only change the “.fn” attribute in attribute editor, you need also change “.fns” in code, which is a string array attribute), here I just copy first path to the string array path

  all_abc_nodes = cmds.ls(type='AlembicNode')
  for each in all_abc_nodes:
      print('------------------')
      print('Fixing node: {0}'.format(each))
      cur_abc_path = cmds.getAttr(each+'.fn')
      cmds.setAttr('{0}.fns'.format(each), 1, cur_abc_path, type='stringArray')

• get 2D screen space from 3D position

  import maya.OpenMayaUI as omui
  import maya.OpenMaya as om
  import maya.cmds as cmds
  obj = cmds.ls(sl=1, fl=1)[0] # get first vtx or object, assume you have selected sth
  pos = om.MPoint(obj)

• get active viewport camera name

  dagPath = om.MDagPath() # dag path holder
  omui.M3dView().active3dView().getCamera(dagPath) # get info
  cam_name = om.MFnDagNode(dagPath.transform()).fullPathName() # get cam name

• get viewport width and height in monitor pixel unit

  omui.M3dView().active3dView().portWidth()
  omui.M3dView().active3dView().portHeight()

• Make Move tool aim to camera, or parallel to camera; Good for matchmove

  '''
  ==========================================
  2019.05.21
  by Shining Ying 
  shiningdesign[with]live.com
   
  make move tool aim to camera (with object/vtx selection)
  ==========================================
  '''
  import maya.cmds as cmds
  import maya.OpenMaya as om
  import math
  def getLocalVecToWorldSpaceAPI(obj, vec=om.MVector.xAxis):
      # ref: http://forums.cgsociety.org/showthread.php?t=1124527
      # take obj's local space vec to workspace, default object x axis
      selList = om.MSelectionList()
      selList.add(obj)
      nodeDagPath = om.MDagPath()
      selList.getDagPath(0, nodeDagPath)
      matrix = nodeDagPath.inclusiveMatrix()
      vec = (vec * matrix).normal()
      return vec.x, vec.y, vec.z
   
  def alignObjectToVector(obj, axis, aim_dir, up_guide_dir = None, side_axis=None, side_guide_dir = None ):
      # grab object transform function lib
      selectionList = om.MSelectionList()
      selectionList.add( obj )
      dagPath = om.MDagPath()
      selectionList.getDagPath(0, dagPath)
      fnTransform = om.MFnTransform(dagPath)
      # axis dict
      axis_dict = {'x':om.MVector.xAxis, 'y':om.MVector.yAxis, 'z':om.MVector.zAxis}
      obj_axis_dir = getLocalVecToWorldSpaceAPI(obj, axis_dict[axis])
      obj_axis_vec = om.MVector(*obj_axis_dir)
   
      aim_vec = om.MVector(*aim_dir)
      rot_quaternion = obj_axis_vec.rotateTo(aim_vec)
      fnTransform.rotateBy(rot_quaternion)
      # optional 2nd axis setup
      if up_guide_dir != None and side_axis != None:
          # based on: aim_vec info
          up_guide_vec = om.MVector(*up_guide_dir)
          # make sure aim is not parallel to up_guide_vec
          if up_guide_vec.isParallel(aim_vec):
              # then align side x to provided backup side axis
              if side_guide_dir != None:
                  alignObjectToVector(obj, side_axis, side_guide_dir)
          else:
              side_vec =  up_guide_vec ^ aim_vec # side dir
              alignObjectToVector(obj, side_axis, (side_vec.x,side_vec.y,side_vec.z ))
   
  cur_selection = cmds.ls(sl=1)
   
  #fixCam= 'camera1'
  fixCam = ''
  cmds.setToolTo('moveSuperContext') # $gMove
  cur_cam = cmds.modelEditor(cmds.playblast(activeEditor=1), q=1, camera=1)
  if fixCam !='':
      cur_cam = fixCam
  print('Aim Camera: {0}'.format(cur_cam))
  camPos = cmds.xform(cur_cam, q=1, t=1, ws=1)
  objPos = cmds.manipMoveContext('Move', q=1, position=1) # only work for 1st time selection, then it got 1/10
  objPos2 = cmds.xform(cur_selection[0],q=1,t=1,ws=1 ) # override with actual measure
  if (objPos[0] - objPos2[0])**2 > 0.000001:
      objPos_maya = objPos 
      objPos = objPos2
      print('Maya make mistake on move tool position, I correct it from {0} to {1}'.format(str(objPos_maya),str(objPos2)))
   
  aim_dir = [a-b for a,b in zip(camPos,objPos)] 
  up_ref_dir = getLocalVecToWorldSpaceAPI(cur_cam, vec=om.MVector.yAxis)
   
  # loc
  tmp_loc = cmds.spaceLocator(n='tmp_move_loc')[0]
  cmds.xform(tmp_loc, t=objPos, ws=1)
  # align
  alignObjectToVector(tmp_loc, 'z', aim_dir, up_guide_dir = up_ref_dir, side_axis='x')
  rot_val = cmds.xform(tmp_loc, q=1, ro=1)
  cmds.delete(tmp_loc)
  # back to old selection
  cmds.select(cur_selection)
  # set tool
  cmds.setToolTo('moveSuperContext')
  cmds.manipMoveContext( 'Move', e=1, activeHandle=2, m=6, orientAxes=[math.radians(a) for a in rot_val])
   
   
  '''
  ==========================================
  2019.05.21
  by Shining Ying 
  shiningdesign[with]live.com
   
  make move tool paralell to camera (with object/vtx selection)
  ==========================================
  '''
   
  cur_selection = cmds.ls(sl=1)
   
  #fixCam= 'camera1'
  fixCam = ''
  cmds.setToolTo('moveSuperContext') # $gMove
  cur_cam = cmds.modelEditor(cmds.playblast(activeEditor=1), q=1, camera=1)
  if fixCam !='':
      cur_cam = fixCam
  print('Aim Camera: {0}'.format(cur_cam))
  # loc
  tmp_loc = cmds.spaceLocator(n='tmp_move_loc')[0]
  # align
  cmds.parentConstraint(cur_cam,tmp_loc)
  rot_val = cmds.xform(tmp_loc, q=1, ro=1)
  cmds.delete(tmp_loc)
  # back to old selection
  cmds.select(cur_selection)
   
  # set tool
  cmds.setToolTo('moveSuperContext')
  cmds.manipMoveContext( 'Move', e=1, activeHandle=2, m=6, orientAxes=[math.radians(a) for a in rot_val])

• the 'defaultRenderGlobals' object, it contains everything in render setting, and can be accessed through this object

  cmds.select('defaultRenderGlobals')
   
  # get current scene name
  cur_scene = cmds.file(q=1, sn=1, shn=1)
  if cur_scene == '':
      cur_scene = 'untitled'
      print('Not Name Yet')
  else:
      cur_scene = cur_scene.rsplit('.',1)[0]
  # get render global output name, update to custom name format
  cur_img_prefix = cmds.getAttr('defaultRenderGlobals.imageFilePrefix')
   
  if '<Scene>' in cur_img_prefix:
      result_txt = cur_img_prefix.replace('<Scene>', cur_scene.rsplit('_',1)[0])
      cmds.setAttr('defaultRenderGlobals.imageFilePrefix',result_txt , type='string' )

  • it maps all the setting in Render Setting - Common Tab,

    image_ext = 'png'
    cmds.setAttr("defaultRenderGlobals.imageFormat", 32) # png
     
    scene_path = os.path.dirname(cmds.file(q=True, sceneName=True))
    dir_path_info = [scene_path, 'images']
    render_root_path = os.path.join(*dir_path_info ).replace('\\','/')
     
    cmds.setAttr("defaultRenderGlobals.imageFilePrefix", render_root_path +'/%s', type='string' )
    # set as name.####.ext format
    cmds.setAttr("defaultRenderGlobals.animation",1) # render multi frame
    cmds.setAttr("defaultRenderGlobals.outFormatControl",0) # use ext
    cmds.setAttr("defaultRenderGlobals.putFrameBeforeExt",1) # use frame num
    cmds.setAttr("defaultRenderGlobals.periodInExt",1) # use .ext
    cmds.setAttr("defaultRenderGlobals.extensionPadding",4) # use padding
     
    # set width
    cmds.setAttr("defaultResolution.w",1920) # use padding
    cmds.setAttr("defaultResolution.h",1080) # use padding

  • it also contains all the Deadline render job setting

• get absolution render output path (including dynamic changing output path)

  cmds.renderSettings(firstImageName=1, fullPath=1)

• get workspace current information

  cmds.workspace(q=1, rootDirectory=True) # root proj dir, holding the scene/image/etc folders
  cmds.workspace(q=1, dir=1) # scene folder full-path
   
  # scene path and scene name
  cmds.file(q=True, sceneName=True)
  cmds.file(q=True, sceneName=True, shortName=True)
   
  # segment subpath
  cmds.workspace(fr=1,q=1) # list of segment sub names
  cmds.workspace(fr=['images', 'images']) # set the segment subpath
  cmds.workspace(fr=['depth', 'renderData/depth']) # set the segment subpath
  cmds.workspace(fileRuleEntry='depth') # get the segment path

• mel to use python write Pre-Render-Mel, to store scene path into render image folder nearby text file (note to escape \ in one line as python(“”) as mel cmd)

  import datetime;
  time_text = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S');
  import maya.cmds as cmds;
  out_path = cmds.renderSettings(firstImageName=1, fullPath=1)[0]; 
  scene_path = cmds.file(q=True, sceneName=True); 
  parent_dir = os.path.dirname(out_path);
  info_file=parent_dir+'.info';
  os.path.exists(os.path.dirname(info_file)) or os.mkdir(os.path.dirname(info_file));
  f = open(info_file,'w');
  f.writelines([scene_path,'\n',time_text]);
  f.close();
  print('Render Info written to {0}'.format(info_file))

• mel version

  python("import datetime;time_text = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S');import maya.cmds as cmds;out_path = cmds.renderSettings(firstImageName=1, fullPath=1)[0]; parent_dir = os.path.dirname(out_path);info_file=parent_dir+'.info';os.path.exists(os.path.dirname(info_file)) or os.mkdir(os.path.dirname(info_file));scene_path = cmds.file(q=True, sceneName=True);f = open(info_file,'w');f.writelines([scene_path,'\\n',time_text]);f.close();print('Render Info written to '.format(info_file))")

• use python to set mel setting, note maya sometimes create another tmp ma file to render, and make scene file not the same, thus need to bake current scene name into it. (note the r'''x''' format to auto escape \, the above code also can use r'x' to simplify the escape need)

  # bake scene name into mel cmd, as render will create a another tmp scene file, which cause get scene name different in script
  scene_path = cmds.file(q=1, sceneName=True)
  pre_mel = r'''python("import datetime;time_text = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S');import maya.cmds as cmds;out_path = cmds.renderSettings(firstImageName=1, fullPath=1)[0]; parent_dir = os.path.dirname(out_path);info_file=parent_dir+'.info';os.path.exists(os.path.dirname(info_file)) or os.mkdir(os.path.dirname(info_file));f = open(info_file,'w');f.writelines(['{0}','\\n',time_text]);f.close();print('Render Info written to {0}'.format(info_file))")'''.format(scene_path)
  # set as per render layer instead pre scene, since each folder has different name
  cmds.setAttr("defaultRenderGlobals.preRenderLayerMel",pre_mel, type="string")

  • preMel: before maya kick render (postMel)
  • preRenderLayerMel: for each render layer, as for each render folder, it do the per render info write (postRenderLayerMel)
  • preRenderMel: per frame (postRenderMel)

• defaultArnoldRenderOptions:
  • the arnold render setting object, contains all render setting for Arnold render

• cross platform maya scene directory mapping and management
  • dirmap command: http://help.autodesk.com/cloudhelp/2017/CHS/Maya-Tech-Docs/Commands/dirmap.html
  • ref: https://fredrikaverpil.github.io/2010/11/24/managing-maya-scenes-on-multiple-platforms/

• get mel system level operation and maya launch directory

  import maya.mel as mel
  print(mel.eval('pwd'))

• Publish workflow
  • http://forums.pyblish.com/
• Project Dir

  cmds.workspace(dir='d:/proj/current')

• File New

  cmds.file(f=1,new=1)

• File Open

  cmds.file(filePath, o=True)
  cmds.file(renameToSave=1) # prevent overwrite save after open

• Importing

  cmds.file(filePath, i=True)

• Reference

  cmds.file(filePath.replace('\\', '/'), r=True, namespace=ns)
  allRefNode = cmds.ls( references=1)
  cur_node = allRefNode[0]
  # get reference used namespace - :MyNameSpace
  cur_ns= cmds.referenceQuery(cur_node, namespace=1)
  # get reference used file - C:/user/myfile.ma
  cur_path = cmds.referenceQuery(cur_node, f=1)
  # get reference used file name - myfile.ma
  cur_name = cmds.referenceQuery(cur_node, f=1, shn=1)

• delete unused node

  mel.eval('MLdeleteUnused')

• checking

  cmds.file(q=1, sn=1) # filepath
  cmds.file(q=1, sn=1, un=1) # filepath in variable format
  cmds.file(q=1, sn=1, shn=1) # filename
  cmds.file(q=1, sn=1, wcn=1) # withoutCopyNumber

• check file change and save

  cmds.file(q=1, modified=1)
  cmds.file(save=1)

• saving as

  # you need to rename first before you can save as
  if ext.lower() == ".ma":
      cmds.file(rename = filePath)
      cmds.file(f=1, save=1, type="mayaAscii")
      save_done = 1
  elif ext.lower() == ".mb":
      cmds.file(rename = filePath)
      cmds.file(f=1, save=1, type="mayaBinary")
      save_done = 1

• export

  if format_info == "ma":
      if self.uiList['publish_selected_check'].isChecked():
          cmds.file(filePath, f=1, type="mayaAscii", pr=1, exportSelected=1)
      else:
          cmds.file(filePath, f=1, type="mayaAscii", pr=1, exportAll=1)
  else:
      if self.uiList['publish_selected_check'].isChecked():
          cmds.file(filePath, f=1, type="mayaBinary", pr=1, exportSelected=1)
      else:
          cmds.file(filePath, f=1, type="mayaBinary", pr=1, exportAll=1)

• mel shelf button

  global string $gShelfTopLevel;
  string $currentShelf = `tabLayout -query -selectTab $gShelfTopLevel`;
  setParent $currentShelf;
  // - step 2: prepare path, name, icon, cmd
  string $name="test";
  string $ver="v1.0";
  string $icon="test.png";
  string $cmd ="ls -sl";
  // - step 3: create shelf btn
  shelfButton -c $cmd -ann $name -l $name -imageOverlayLabel $ver -overlayLabelColor 0 0 0 -overlayLabelBackColor 0 0 0 0.0 -image $icon -image1 $icon -sourceType "mel";
   
  shelfButton -c $cmd -ann $name -l $name -imageOverlayLabel $ver -overlayLabelColor 0 0 0 -overlayLabelBackColor 1 1 1 0.5 -image $icon -image1 $icon -sourceType "mel";
   
  string $curBtn = `shelfButton -parent $currentShelf -c $cmd -mi "reload" "print ok" -ann $name -l $name -imageOverlayLabel $ver -overlayLabelColor 0 0 0 -overlayLabelBackColor 0 0 0 0.0 -image $icon -image1 $icon -sourceType "mel"`;
  string $curPop = `popupMenu -parent $curBtn -button 1 -ctl 1`; // sh, alt, ctl
  menuItem -p $curPop -l "A A A" -c "print A";
  menuItem -p $curPop -l "Reload" -c "print reload";

• shelf operation with python

  import maya.cmds as cmds
  import maya.mel as mel
  shelf_holder = mel.eval('$tmpVar=$gShelfTopLevel') # get tab holder
  shelves = cmds.tabLayout(shelf_holder, q=1, selectTab=1) # get selected tab
  shelves = cmds.tabLayout(shelf_holder, q=1, childArray=1) # names of the layout's immediate children.
  cmds.shelfTabLayout(e=1, selectTabIndex=3, shelf_holder) # change active tab by index
  cmds.shelfTabLayout(shelf_holder, e=1, selectTab = shelf_name) # change active tab by name
  cmds.shelfLayout(shelf_name, ex=True) # check shelf exists by name
   
  shelf_name = mel.eval('addNewShelfTab %s' % shelf_name) # add shelf
  mel.eval('deleteShelfTab %s' % shelf_name) # delete shelf
   
  cmds.saveAllShelves(shelf_holder) # save all shelfs

• Maya path customize: It looks like maya only initialize those PATHs info during startup, manually add them after restart, maya still complain can't find the path. So use following method first.
  1. maya.env method (It loads before UI, before userSetup.py)

     USER_SCRIPT_PATH1=C:/myscripts/whatever/path1
     USER_SCRIPT_PATH2=C:/myscripts/whatever/path2
     MAYA_SCRIPT_PATH=$MAYA_SCRIPT_PATH;$USER_SCRIPT_PATH1;USER_SCRIPT_PATH2
     MAYA_MODULE_PATH = D:\MayaModule\mgear_3.5.1
     MAYA_PLUG_IN_PATH = D:\whatever\plugin
     PYTHONPATH = D:\whatever\scripts

  2. userSetup.py method (load after env, before UI) (~\Documents\maya\version\scripts)

     print("\nLoading Pipeline from userSetup.py\n")

  3. userSetup.mel method (load after UI loaded) (~\Documents\maya\version\scripts)

     print("\nLoading Pipeline from userSetup.mel\n");
     $path1 = "C:/myscripts/whatever/path1";
     $path2 = "C:/myscripts/whatever/path2";
     string $newScriptPath = $path1 + ";" +  $path2 + ";" +`getenv "MAYA_SCRIPT_PATH"`;
     putenv "MAYA_SCRIPT_PATH" $newScriptPath;
      
     // or source other config script
     $script1 = "C:/myscripts/whatever/script1.mel";
     $script2 = "C:/myscripts/whatever/script2.mel";
     source $script1;
     source $script2;

  4. cmd or bash shell method (run after userSetup.mel)

     // bash
     alias proj1="export MAYA_SCRIPT_PATH=path/to/scripts:$MAYA_SCRIPT_PATH; maya;"
     // dos
     set MAYA_MODULE_PATH=R:/Pipeline/maya/modules;
     "C:/Program Files/Autodesk/Maya2020/bin/maya.exe" -c "python(\"print('Loading Pipeline from Launch Cmd')\")"