在maya python中选择子对象

Question

我目前正在尝试为 DAG 节点的每个子对象赋予不同的颜色。当我在组件选择模式下选择每个子对象/元素（但不是全部）然后在其上运行脚本时，它会起作用。但是选择整个网格对我不起作用。我已经尝试过不同种类的 listRelatives 但没有一个奏效。我可以进入对象并获取每个顶点，但它们没有按连通性分组。

    def assignDMat(self,*args):
    #selection = self.selector()
    selection = cmds.ls(selection=True)
    for j in range(0, len(selection)):
        cmds.polyColorPerVertex(selection[j], r=0,  g=0, b=0, cdo=True)
        cmds.polyColorPerVertex(selection[j], r=random.uniform(0,1), cdo=True)

新代码：

import maya.cmds as cmds
import random

selection = cmds.ls(selection=True)

cmds.polySeparate(selection)


for i in range(0,len(selection)):
    obj=cmds.listRelatives(selection[i])
    print(len(obj))
    for j in range(0,len(obj)-1):
        cmds.polyColorPerVertex(obj[j], r=0,  g=0, b=0, cdo=True)
        cmds.polyColorPerVertex(obj[j], r=random.uniform(0,1), cdo=True)

cmds.polyUnite(("polySurface*"), n="Result", ch=False)

Intended Result

Answer 1

使用分离然后重新合并网格可能会导致许多意想不到的问题，其中一些您已经遇到过，因此最好避免这种情况。

相反，我们可以创建一个函数，通过返回一组人脸索引列表来返回对象的所有单独外壳。这可以使用cmds.polySelect 来完成，将面部索引传递给它，然后它将选择整个外壳。由于现在选择了外壳，我们现在可以收集新选择并继续获取下一个外壳。然后，很容易循环遍历它们并用cmds.polyColorPerVertex为它们着色。

这是一个示例，它将创建随机数量的多边形球体，将它们全部组合起来，然后为每个外壳设置随机颜色：

import random
import maya.cmds as cmds


# Just makes a bunch of random spheres, combines them, then returns the new mesh.
def make_bunch_of_spheres():
    meshes = []

    for i in range(random.randint(20, 50)):
        meshes.append(cmds.polySphere()[0])
        cmds.move(random.randint(-20, 20), random.randint(-20, 20), random.randint(-20, 20), meshes[-1])

    return cmds.polyUnite(meshes, constructionHistory=False)[0]


def get_shell_faces():
    shells = []  # We'll be putting in lists of face indexes in here later. Each sub-list will represent a separate shell.

    sel = cmds.ls(sl=True)

    for obj in sel:
        faces = cmds.ls(obj + ".f[*]", flatten=True)  # Get all face indexes from the object.

        for face in faces:
            index = int(face.split("[")[1].rstrip("]"))  # Extract the faces index number.
            cmds.polySelect(obj, extendToShell=index)  # Use the face's index to select the whole shell.

            new_faces = cmds.ls(sl=True, flatten=True)  # Now that the shell is selected, capture its faces.
            shells.append(new_faces)  # Append the face's as a new shell.

            # Remove indexes from the new shell from this current loop, to optimize, and to avoid adding duplicate shells.
            for new_face in new_faces:
                if new_face in faces:
                    faces.pop(faces.index(new_face))

    cmds.select(sel)  # Restore selection.

    return shells


# Create a bunch of combined spheres then select it.
new_mesh = make_bunch_of_spheres()
cmds.select(new_mesh)

shells = get_shell_faces()  # Get shells from selection.

# Color each shell!
for shell in shells:
    cmds.polyColorPerVertex(shell, r=random.random(),  g=random.random(), b=random.random(), cdo=True)

Answer 2

import random
obj = cmds.ls(selection=True)
obj_vtx = [cmds.ls(o + '.vtx[*]', fl=True) for o in obj]
for obj in obj_vtx:
    color_id = random.uniform(0,1)
    for vtx in obj:
        cmds.polyColorPerVertex(vtx, r=0,  g=0, b=0, cdo=True)
        cmds.polyColorPerVertex(vtx, r=color_id, cdo=True)

编辑：将颜色放入对象循环中

Answer 3

目前有效的解决方案。它没有任何故障保险。例如，如果对象没有父对象，它可能会出错。就我而言，这是可行的。 非常感谢您的意见，DrWeeny。

import maya.cmds as cmds
import random

par=cmds.listRelatives(cmds.ls(selection=True),p=True)
selection = cmds.ls(selection=True)
cmds.select(selection)

pivotTranslate = cmds.xform (selection[0], q = True, ws = True, rotatePivot = True)




print(piv)
cmds.polySeparate(selection)


for i in range(0,len(selection)):
    obj=cmds.listRelatives(selection[i])
    print(len(obj))
    for j in range(0,len(obj)-1):
        cmds.polyColorPerVertex(obj[j], r=0,  g=0, b=0, cdo=True)
        cmds.polyColorPerVertex(obj[j], r=random.uniform(0,1), cdo=True)

cmds.polyUnite(("polySurface*"), n=selection[0], ch=False)
cmds.xform (selection[0], ws = True, pivots = pivotTranslate)
cmds.select(par)
cmds.parent(selection[0])