求助：Maya中Python大模型UV壳分块循环实现方法

在Maya中使用Python为模型随机分配颜色时，处理1万多边形以内的模型运行正常，但处理10万面的大模型会崩溃。需要通过分块循环优化：每次处理100个元素，批次间加入time.sleep()释放资源（不提升速度但避免崩溃）。目前仅能实现前100个元素的处理逻辑，求可循环处理所有分块的完整代码。

当前尝试的代码片段：

for i, n in enumerate(uvShellIds):
    # 仅能处理前100个元素的逻辑
    limit = 100 
    if 0 <= i <= 100:
        # 执行操作
        print(n)

# 需要扩展为循环处理后续每100个元素的逻辑
# if 101 <= i <= 200:
# (...以此类推...) 

完整原始代码：

import maya.OpenMaya as om
import maya.cmds as cmds
import random
 
def getUvShelList(name):
    selList = om.MSelectionList()
    selList.add(name)
    selListIter = om.MItSelectionList(selList, om.MFn.kMesh)
    pathToShape = om.MDagPath()
    selListIter.getDagPath(pathToShape)
    meshNode = pathToShape.fullPathName()
    uvSets = cmds.polyUVSet(meshNode, query=True, allUVSets =True)
    allSets = []
    for uvset in uvSets:
        shapeFn = om.MFnMesh(pathToShape)
        shells = om.MScriptUtil()
        shells.createFromInt(0)
        nbUvShells = shells.asUintPtr()
 
        uArray = om.MFloatArray()   # U坐标数组
        vArray = om.MFloatArray()   # V坐标数组
        uvShellIds = om.MIntArray() # UV壳ID容器
 
        shapeFn.getUVs(uArray, vArray)
        shapeFn.getUvShellsIds(uvShellIds, nbUvShells, uvset)
 
        shells = {}
        for i, n in enumerate(uvShellIds):
            limit = 100
            if i <= limit:
                if n in shells:
                    shells[n].append( '%s.map[%i]' % ( name, i ) )
                else:
                    shells[n] = [ '%s.map[%i]' % ( name, i ) ]

        allSets.append({uvset: shells})
    
    for shell in shells:
        selection_shell = shells.get(shell)
        cmds.select(selection_shell)
        facesSel = cmds.polyListComponentConversion(fromUV=True, toFace=True)
        cmds.select(facesSel)
        r = [random.random() for i in range(3)]
        cmds.polyColorPerVertex(facesSel,rgb=(r[0], r[1], r[2]), cdo=1 )
        cmds.select(deselect=1)
 
getUvShelList( 'polySurface359' )

优化后的分块处理代码 #

核心改动是实现分批次收集UV壳数据，每处理100个元素就执行着色操作并休眠，同时清空临时数据释放内存：

import maya.OpenMaya as om
import maya.cmds as cmds
import random
import time  # 引入休眠模块

def getUvShelList(name):
    selList = om.MSelectionList()
    selList.add(name)
    selListIter = om.MItSelectionList(selList, om.MFn.kMesh)
    pathToShape = om.MDagPath()
    selListIter.getDagPath(pathToShape)
    meshNode = pathToShape.fullPathName()
    uvSets = cmds.polyUVSet(meshNode, query=True, allUVSets =True)
    
    batch_size = 100  # 每批次处理元素数量
    sleep_time = 0.1  # 批次间休眠时间（可调整）
    
    for uvset in uvSets:
        shapeFn = om.MFnMesh(pathToShape)
        shells = om.MScriptUtil()
        shells.createFromInt(0)
        nbUvShells = shells.asUintPtr()
 
        uArray = om.MFloatArray()
        vArray = om.MFloatArray()
        uvShellIds = om.MIntArray()
 
        shapeFn.getUVs(uArray, vArray)
        shapeFn.getUvShellsIds(uvShellIds, nbUvShells, uvset)
 
        current_shells = {}
        for i, n in enumerate(uvShellIds):
            # 收集当前UV壳的组件
            if n in current_shells:
                current_shells[n].append( '%s.map[%i]' % ( name, i ) )
            else:
                current_shells[n] = [ '%s.map[%i]' % ( name, i ) ]
            
            # 达到批次上限，或者处理到最后一个元素时执行着色
            if (i + 1) % batch_size == 0 or i == len(uvShellIds) - 1:
                # 处理当前批次的UV壳
                for shell_id, components in current_shells.items():
                    facesSel = cmds.polyListComponentConversion(components, fromUV=True, toFace=True)
                    r = [random.random() for _ in range(3)]
                    cmds.polyColorPerVertex(facesSel, rgb=(r[0], r[1], r[2]), cdo=1)
                
                # 清空临时数据，释放内存
                current_shells.clear()
                # 批次间休眠
                time.sleep(sleep_time)
                # 强制Maya刷新UI（可选，避免假死）
                cmds.refresh()

getUvShelList( 'polySurface359' )

关键优化点说明 #

• 分批次处理：通过(i + 1) % batch_size == 0判断批次边界，每收集100个元素就立即处理，避免一次性加载大量数据到内存。
• 内存释放：每批次处理完成后清空current_shells字典，释放占用的内存。
• 休眠与刷新：添加time.sleep()让Maya有时间处理后台任务，配合cmds.refresh()避免UI假死。
• 移除冗余操作：删除了不必要的cmds.select()调用，直接用组件执行转换和着色，减少交互开销。

内容的提问来源于stack exchange，提问作者johancc