Versioning with Previews in Maya

'''
Name: scene-preview.py
Version: 1.0.0
Author: gfxhacks.com
Desc: Captures and saves a scene preview based on the active viewport, at the current frame. Uses playblast feature.
'''

import maya.cmds as cmds
import os
import time

# set screenshot dimensions
width = 960
height = 540

# get active viewport panel
panel = cmds.getPanel( withFocus=True )

# throw error if active panel is not a viewport
if "modelPanel" not in cmds.getPanel(typeOf=panel):
	cmds.confirmDialog( title='Error!', message='Please select a viewport panel first.', button=['Ok'], defaultButton='Ok', dismissString='No' )
	raise RuntimeError('Error: Please select a viewport panel, then try again.')

# get current frame number
curFrame = int(cmds.currentTime( query=True ))

# get name of current file
scName = cmds.file( query=True, sn=True, shn=True )

# get path of current file
scPath = cmds.file( query=True, sn=True )

# set new path where previews will be saved to
path = scPath + "-prv/"

# get name of current camera
cam = cmds.modelEditor( panel, query=True, camera=True )

# get current timestamp
ts = int( time.time() )

# construct full path
fullPath = "{}{}-{}-f{}-{}.jpg".format( path, scName, cam, curFrame, ts )

# Create path if it doesn't exist
if not os.path.exists( path ):
    os.makedirs(path)

# run playblast for current viewport
cmds.playblast( fr=curFrame, v=False, fmt="image", c="jpg", orn=False, cf=fullPath, wh=[width,height], p=100 )

# log path to console for reference
print('Snapshot saved as: ' + fullPath )

# show popup message in viewport
cmds.inViewMessage( amg='<span style="color:#82C99A;">Snapshot saved</span> for <hl>' + cam + '</hl> in <hl>' + scName + '<hl> at frame <hl>' + str(curFrame) + '</hl>', pos='topRight', fade=True, fst=3000 )

# set screenshot dimensions
width = 960
height = 540

# throw error if active panel is not a viewport
if "modelPanel" not in cmds.getPanel(typeOf=panel):

# get name of current camera
cam = cmds.modelEditor( panel, query=True, camera=True )

# get name of current file
scName = cmds.file(query=True, sn=True, shn=True)

# get full path of current file
scPath = cmds.file(query=True, sn=True)

# set new path where previews will be saved to
path = scPath + "-prv/"

os.makedirs(path)

# construct full path
fullPath = "{}{}-{}-f{}-{}.jpg".format(path, scName, cam, curFrame, ts)

# run playblast for current viewport
cmds.playblast(fr=curFrame, v=False, fmt="image", c="jpg", orn=False, cf=fullPath, wh=[width,height], p=100)

'''
fr: frame range
v: launches a viewer, like a 'fcheck', for images - once the render is done.
fmt: format
	fmt="movie"
    fmt="image"
c: compression
	c="none": .iff
    omitted: will use render settings.
orn: Show the viewport ornaments (any HUD items). On by default.
cf: complete filename. There is also the f (filename) flag for specifying just
	the filename and use the default path set in the Render Settings.
p: Percentage of viewport. This scales the output unless set to 100%.
	Default is 50% (half resolution).
'''

cmds.confirmDialog(title='Error!', message='Please select a viewport panel first.', button=['Ok'], defaultButton='Ok', dismissString='No')

# log path to console for reference
print('Snapshot saved as: ' + fullPath)

# show popup message in viewport
cmds.inViewMessage(amg='<span style="color:#82C99A;">Snapshot saved</span> for <hl>' + cam + '</hl> in <hl>' + scName + '<hl> at frame <hl>' + str(curFrame) + '</hl>', pos='topRight', fade=True, fst=3000)

'''
amg: message to be displayed. Allows for some HTML tags.
	In our case we used <span> so we could assign a custom color.
    The <hl> tag is not an HTML tag but is handled as one - it
    highlights the contained text.
fade: allows message to fade out.
fst: Fade Stay Time - how long the image stays at max opacity (milliseconds).

pos: position of the message in the viewport.

   "topLeft"
   "topCenter"
   "topRight"
   "midLeft"
   "midCenter"
   "midCenterTop"
   "midCenterBot"
   "midRight"
   "botLeft"
   "botCenter"
   "botRight"
   
'''