Get all child attributes of compound node when one sibling changes

[Michael Kato]

Hi all,

I've having a load of trouble with this. I've managed to get some complex (for me anyway) compound attributes set up and connected to objects in my scene, but right now I'm unable to get the "Blend Shape Multi Input" attribute to arrive as a plug to the compute() method in my scripted node. 

So I resorted to some trickery by looking for the "blendWeight" attribute instead when it changes, then getting om.MDataPlug.parent() which is the compound node, then re-getting the children of that compound node and their data. 

My attributes look like this

All of this works except for one crucial thing, calling asMDataHandle()

childData = childPlug.asMDataHandle().data()

This seems to force the recompute of some things and sends my plugin into an infinite loop. Is there a better way to do this?

Code attached, it should work in maya 2018 (possibly earlier) in a scene with some blendshapes in it if you call connectBlendShapeNodes()

Thanks for any help!

[Rémi Deletrain]

Hi Michael,

You can get compound attribute like this.

def compute(self, plug, dataBlock):

   

   #   Compute only on input compound attribute

   a_valid_attr = [self.attrIn_tensionColor_01, self.attrIn_tensionIndex_01, self.attrIn_blendWeight]

   if plug not in a_valid_attr:

       return

   #   Get CompoundAttribute array handle

   ah_bs_multi_input = data.inputArrayValue(self.attrIn_blendShapeMultiInput)

   i_input_count = ah_bs_multi_input.elementCount()

   #   Iter on element count

   for i in xrange(i_input_count):

       #   Get compound handle

       ah_bs_multi_input.jumpToElement(i)

       h_bs_multi_input = ah_bs_multi_input.inputValue()

       #   Get compound children handle

       h_tension_color = h_bs_multi_input.child(0) # cls.attrIn_tensionColor_01

       h_tension_index = h_bs_multi_input.child(0) # cls.attrIn_tensionIndex_01

       h_blend_weight = h_bs_multi_input.child(0) # cls.attrIn_blendWeight

[Rémi Deletrain]

Oh sorry I'm make a mistake

#   Get compound children handle

h_tension_color = h_bs_multi_input.child(0) # cls.attrIn_tensionColor_01

h_tension_index = h_bs_multi_input.child(1) # cls.attrIn_tensionIndex_01

h_blend_weight = h_bs_multi_input.child(2) # cls.attrIn_blendWeight

[Michael Kato]

Thanks for the help Remi!

Your method didn't work for me right away but was a big help. Knowing that I can get any attribute I want inside the compute() without relying on the datablock being passed in was pivotal along with some of your other examples, like getting the children of the compound attribute. I had to use direct references to the MObjects themselves instead of indices, however.

In the end I used this and it mostly works, except that sometimes the IntArray attribute doesn't have any data in it, not sure why yet.

def compute(self, plug, dataBlock):

if plug.attribute() == self.attrIn_blendWeight:

inputAttrs = [self.attrIn_tensionColor_01, self.attrIn_tensionIndex_01, self.attrIn_blendWeight]

multiInputArrayHandle = dataBlock.inputArrayValue( self.attrIn_blendShapeMultiInput )

while not multiInputArrayHandle.isDone():

multiInputHandle = multiInputArrayHandle.inputValue()

tensionColorHandle = multiInputHandle.child( inputAttrs[0] )

tensionIndexHandle = multiInputHandle.child( inputAttrs[1] )

blendWeightHandle = multiInputHandle.child( inputAttrs[2] )

tensionColorData = tensionColorHandle.data()

tensionIndexData = tensionIndexHandle.data()

tensionColor = om.MFnDoubleArrayData( tensionColorData ).array()

try:

tensionIndex = om.MFnIntArrayData( tensionIndexData ).array()

except:

multiInputArrayHandle.next()

continue

blendWeight = blendWeightHandle.asFloat()

print tensionColor

print tensionIndex

print blendWeight

try:

rgbValues = self.sortRGB( tensionIndex, tensionColor )

print "Done", rgbValues

except:

print "Bad stuff"

# next!

multiInputArrayHandle.next()

[Rémi Deletrain]

I gave you an example in API 1.0. There are differences between the two APIs. I have never worked with API 2.0.

Your attributeAffects is not valid. The first argument must be an inputAttribute ans second must be outputAttribute.

cls.attributeAffects( cls.attrIn_blendWeight, cls.attrIn_blendShapeMultiInput )

In your code you have two inputAttribute and with this error your imputeAttribute never affect outputAttribute.

cls.attributeAffects(cls.attrIn_blendShapeMultiInput, cls.attrOut_colorPerVertex)

In compute you must clean attribute.

add this code at the end of compute

data.setClean(plug)

[Michael Kato]

Thanks again Remi, unfortunately yeah I went with API 2.0 to see the state of things... so far I have no complaints except that it makes implementing other people's code harder. Things are finally working after more fiddling and some pretty disgusting hacks which I'll eventually have to fix.

I'm really not sure if this needed to be an API plugin at all but it was good practice.

Here's a video! The Shape Editor was hidden somehow during capture

https://imgur.com/a/X2chB0h

import sys

import os

import re

from collections import defaultdict

import pymel.core as pm

import maya.api.OpenMaya as om

def maya_useNewAPI():

pass

def pluginLoader(load):

"""

Load or Unload the plugin defined in this module.

Parameters:

load : bool : True to load the plugin, False to unload it.

"""

global __file__

if __file__.endswith('.pyc'):

__file__ = __file__ [:-1]

_, plugin = os.path.split(__file__)

pluginName = plugin.split('.')[0]

if load:

if not pm.pluginInfo(plugin, query=True, loaded=True):

pm.loadPlugin(__file__, quiet=True)

else:

if pm.pluginInfo(plugin, query=True, loaded=True):

pm.flushUndo()

pm.unloadPlugin(plugin, force=True)

return pluginName

def getBlendShapeMesh():

blendShapes = pm.ls( type = pm.nt.BlendShape )

for bs in blendShapes:

blendShapeInputs = bs.getGeometry()

return pm.PyNode( blendShapeInputs[0] )

def getBlendShapeAttrs():

blendShapes = pm.ls( type = pm.nt.BlendShape )

data = defaultdict(list)

data[0] = blendShapes

for bs in blendShapes:

blendShapeInputs = bs.getGeometry()

for bsi in blendShapeInputs:

bsiNode = pm.PyNode(bsi)

attrs = bsiNode.listAttr()

for attr in attrs:

foundColor = attr.find('_TC') > -1

foundIndex = attr.find('_TI') > -1

if foundColor or foundIndex: # regular string search fails on certain attributes

attrAlias = attr.attrName().split('_')[0]

data[attrAlias].append(attr)

return data

def connectBlendShapeNodes():

blendShapeAttrs = getBlendShapeAttrs()

# load the plugin

plugin = pluginLoader(True)

pluginNode = pm.createNode(TensionMapBlender.nodeName)

pluginAttrs = pluginNode.listAttr()

blendShape = blendShapeAttrs.pop(0)[0] # TODO: support multiple blend shapes

i = 0

for attrAlias, attrs in blendShapeAttrs.items():

for attr in attrs:

if '_TC' in attr.attrName():

# >> is Pymel syntax to connect an attribute

attr >> pluginNode.blendShapeMultiInput[i].tensionColor

if '_TI' in attr.attrName():

attr >> pluginNode.blendShapeMultiInput[i].tensionIndex

else:

attr = pm.PyNode( blendShape + '.' + attrAlias )

attr >> pluginNode.blendShapeMultiInput[i].blendWeight

i += 1

class TensionMapBlender(om.MPxNode):

nodeName = 'tensionMapBlender'

nodeId = om.MTypeId( 0xDAE1 )

attrIn_blendShapeMultiInput = om.MObject()

attrIn_tensionColor_01 = om.MObject()

attrIn_tensionIndex_01 = om.MObject()

attrIn_blendWeight = om.MObject()

"""

attrOut_outputMesh = om.MObject()

# Attribute hierarchy goes: colorPerVertex > vertexColor > vertexColorRGB >> vertexColorR,G,B

attrOut_colorPerVertex = om.MObject()

attrOut_vertexColor = om.MObject()

attrOut_vertexColorRGB = om.MObject()

attrOut_vertexAlpha = om.MObject()

attrOut_colorPerFaceVertex = om.MObject()

attrOut_vertexFaceColor = om.MObject()

attrOut_vertexFaceColorRGB = om.MObject()

attrOut_vertexFaceAlpha = om.MObject()

"""

def __init__(self):

''' constructor '''

om.MPxNode.__init__(self)

def compute(self, plug, dataBlock):

if plug == self.attrIn_blendWeight:

multiInputArrayHandle = dataBlock.inputArrayValue( self.attrIn_blendShapeMultiInput )

mergedVertColors = {}

while not multiInputArrayHandle.isDone():

multiInputHandle = multiInputArrayHandle.inputValue()

tensionColorHandle = multiInputHandle.child( self.attrIn_tensionColor_01 )

tensionIndexHandle = multiInputHandle.child( self.attrIn_tensionIndex_01 )

blendWeightHandle = multiInputHandle.child( self.attrIn_blendWeight )

tensionColorData = tensionColorHandle.data()

tensionIndexData = tensionIndexHandle.data()

tensionColor = om.MFnDoubleArrayData( tensionColorData ).array()

try:

tensionIndex = om.MFnIntArrayData( tensionIndexData ).array()

except:

multiInputArrayHandle.next()

continue

blendWeight = blendWeightHandle.asFloat()

#print tensionColor

#print tensionIndex

#print blendWeight

try:

mergedVertColors = self.mergeVertColors( mergedVertColors, tensionColor, tensionIndex )

#print "Done", mergedVertColors

except:

multiInputArrayHandle.next()

continue

# next!

multiInputArrayHandle.next()

# this is ultra hacky

mesh = getBlendShapeMesh()

for index, color in mergedVertColors.items():

#print index

#print color

blendedValues = []

for i in color:

blendedValues.append( i * blendWeight )

blendedColor = om.MColor( blendedValues, model=om.MColor.kRGB, dataType=om.MColor.kFloat )

mesh.setVertexColor(blendedColor.getColor(), index)

# for some reason setVertexColor works but setVertexColors doesn't, arg

#mesh.setVertexColors( mergedVertColors.values(), mergedVertColors.keys() )

# is this plug actually dirty though? guess it can't hurt

dataBlock.setClean(plug)

def mergeVertColors(self, mergedColors, vertColors, vertIndices):

for color, index in zip(vertColors, vertIndices):

# make vectors

if color < 1:

color = om.MColor( [0, 0, color], model=om.MColor.kRGB, dataType=om.MColor.kFloat )

if color >= 1:

color -= 1

color = om.MColor( [color, 0, 0], model=om.MColor.kRGB, dataType=om.MColor.kFloat )

if index in mergedColors:

temp = mergedColors[index] + color

newColor = []

# clamp values to a max of 1

for i in temp:

if i >= 1:

newColor.append(i)

else:

newColor.append(1)

mergedColors[index] = newColor

else:

mergedColors[index] = color

return mergedColors

@classmethod

def nodeCreator(cls):

''' creates and instance of out node class and delivers to to maya as a pointer '''

return cls()

@classmethod

def nodeInitializer(cls):

''' defines the input and output attributes as static variables in our plugin '''

blendShapeMultiInput = om.MFnCompoundAttribute()

doubleArrayAttrFn = om.MFnGenericAttribute()

intArrayAttrFn = om.MFnGenericAttribute()

intAttrFn = om.MFnNumericAttribute()

''' input attributes '''

cls.attrIn_blendShapeMultiInput = blendShapeMultiInput.create( 'blendShapeMultiInput', 'mai' )

cls.attrIn_tensionColor_01 = doubleArrayAttrFn.create( 'tensionColor', 'tc' )

cls.attrIn_tensionIndex_01 = intArrayAttrFn.create( 'tensionIndex', 'ti' )

cls.attrIn_blendWeight = intAttrFn.create( 'blendWeight', 'bw', om.MFnNumericData.kFloat )

doubleArrayAttrFn.addDataType( om.MFnData.kDoubleArray )

intArrayAttrFn.addDataType( om.MFnData.kIntArray )

blendShapeMultiInput.array = True

blendShapeMultiInput.addChild( cls.attrIn_tensionColor_01 )

blendShapeMultiInput.addChild( cls.attrIn_tensionIndex_01 )

blendShapeMultiInput.addChild( cls.attrIn_blendWeight )

cls.addAttribute( cls.attrIn_blendShapeMultiInput )

"""

typedAttribute = om.MFnTypedAttribute()

cls.attrOut_outputMesh = typedAttribute.create("outMesh", "om", om.MFnData.kMesh, om.MObject.kNullObj )

cls.addAttribute( cls.attrOut_outputMesh )

### keeping this around because it took a lot of work to make ###

''' output attributes '''

numAttrFn = om.MFnNumericAttribute()

out_compAttrFn_parent = om.MFnCompoundAttribute()

out_compAttrFn_child1 = om.MFnCompoundAttribute()

out_compAttrFn_child2 = om.MFnCompoundAttribute()

cls.attrOut_colorPerVertex = out_compAttrFn_parent.create( 'colorPerVertex', 'cpvo' )

cls.attrOut_vertexColor = out_compAttrFn_child1.create( 'vertexColor', 'vco' )

cls.attrOut_vertexColorRGB = numAttrFn.createColor( 'vertexColorRGB', 'vcrgbo')

cls.attrOut_vertexAlpha = numAttrFn.create( 'vertexAlpha', 'vao01', om.MFnNumericData.kFloat)

cls.attrOut_vertexFaceColor = out_compAttrFn_child2.create( 'vertexFaceColor', 'vfco' )

cls.attrOut_vertexFaceColorRGB = numAttrFn.createColor( 'vertexFaceColorRGB', 'vcfrgbo')

cls.attrOut_vertexFaceAlpha = numAttrFn.create( 'vertexFaceAlpha', 'vfao', om.MFnNumericData.kFloat)

out_compAttrFn_parent.addChild( cls.attrOut_vertexColor )

out_compAttrFn_child1.array = True

out_compAttrFn_child1.addChild( cls.attrOut_vertexColorRGB )

out_compAttrFn_child1.addChild( cls.attrOut_vertexAlpha )

out_compAttrFn_child1.addChild( cls.attrOut_vertexFaceColor )

out_compAttrFn_child2.array = True

out_compAttrFn_child2.addChild( cls.attrOut_vertexFaceColorRGB )

out_compAttrFn_child2.addChild( cls.attrOut_vertexFaceAlpha )

cls.addAttribute( cls.attrOut_colorPerVertex )

"""

cls.attributeAffects( cls.attrIn_blendWeight, cls.attrIn_blendShapeMultiInput )

def initializePlugin( mobject ):

''' initliize the plug-in'''

mPlugin = om.MFnPlugin( mobject )

try:

mPlugin.registerNode( TensionMapBlender.nodeName, TensionMapBlender.nodeId, TensionMapBlender.nodeCreator, TensionMapBlender.nodeInitializer )

print "Loaded plugin"

except:

sys.stderr.write( 'Failed to register node: ' + TensionMapBlender.nodeName )

raise

def uninitializePlugin( mobject ):

''' uninitialize the plugin'''

mPlugin = om.MFnPlugin( mobject )

try:

mPlugin.deregisterNode( TensionMapBlender.nodeId )

print "Unloaded plugin"

except:

sys.stderr.write( 'Failed to deregister node: ' + TensionMapBlender.nodeName )

raise

On Wednesday, August 29, 2018 at 6:32:45 PM UTC-7, Michael Kato wrote: