在Python中从Maya运行cmd.exe命令的列表

Question

I am writing a maya python script to batch render a scene into jpgs then use ffmpeg to turn them into a mov. Currently the script saves a string of commands as a bat file which works fine but I'd prefer to just run cmd.exe from maya and execute the list of commands without creating that bat first.

I've been reading about "subprocess.popen()" but I can't figure out how to get it to iterate through each line, run that command, then move onto the next one when done ie:

1) Run maya render.exe & save scene as jpegs

2) ffmpeg jpgs to mov

I've shortened the directories but its essentially this:

`C:\PROGRA~1\Autodesk\Maya2015\bin\Render.exe -r hw2 -s 100 -e 200 -of jpg -fnc 7 -x 1920 -y 1080 -rd 
"C:\RENDER" 
"C:\SCENE.ma" ffmpeg -y -r 25 -start_number 0100 -i C:\SCENE_%%04d.jpg C:\SCENE.mov

How would I be able to do this?

Thanks!

Answer 1

first_process = subprocess.Popen(r'RenderCommand', stdout=subprocess.PIPE,stderr=subprocess.PIPE,shell=True )
first_out,first_err = first_process.communicate()
first_exicode = first_process.returncode
print(first_out)
if str(first_exicode) != '0':
    print(first_err)

second_process = subprocess.Popen(r'SecondCommand', stdout=subprocess.PIPE,stderr=subprocess.PIPE,shell=True )
second_out,second_err = second_process.communicate()
second_exicode = second_process.returncode
print(second_out)
if str(second_exicode) != '0':
    print(second_err)

third_process = subprocess.Popen(r'ConvertCommand', stdout=subprocess.PIPE,stderr=subprocess.PIPE,shell=True )
third_out,third_err = third_process.communicate()
third_exicode = third_process.returncode
print(third_out)
if str(third_exicode) != '0':
    print(third_err)

Important note:

During the execution of each Popen(), Maya's GUI will be frozen. This can be really inconvenient especially if you have a lot of frames to render.

I'd recommand you to separate your Render and Convert calls from your main script to avoid this.

You can do it this way:

In your main script (where you would have called your Popen() :

subprocess.Popen(r'mayapy.exe R:\\paul\\Trash\\render_and_convert.py 50 100 150', False)

This command will not freeze Maya's GUI. You can pass arguments from your main script to render_and_convert.py (file paths, start/end frames, etc...)

render_and_convert.py:

import sys
import subprocess
import maya.standalone as std
std.initialize(name='python')
import maya.cmds as cmds
import maya.mel as mel

# store the arguments in variables
first_argument  = sys.argv[1] # =50
second_argument = sys.argv[2] # =100
third_argument  = sys.argv[3] # =150

first_process = subprocess.Popen(r'RenderCommand ' + first_argument + ' ' + second_argument,stdout=subprocess.PIPE,stderr=subprocess.PIPE,shell=True )
first_out,first_err = first_process.communicate()
first_exicode = first_process.returncode
print(first_out)
if str(first_exicode) != '0':
    print(first_err)

second_process = subprocess.Popen(r'SecondCommandWithoutArgs', stdout=subprocess.PIPE,stderr=subprocess.PIPE,shell=True )
second_out,second_err = second_process.communicate()
second_exicode = second_process.returncode
print(second_out)
if str(second_exicode) != '0':
    print(second_err)

third_process = subprocess.Popen(r'ConvertCommand ' + third_argument,stdout=subprocess.PIPE,stderr=subprocess.PIPE,shell=True )
third_out,third_err = third_process.communicate()
third_exicode = third_process.returncode
print(third_out)
if str(third_exicode) != '0':
    print(third_err)