How To Know When Batch Rendering Is Done?

[garyfixler]

I've had quite a night, learning about the complexities inherent in rendering through MEL. Here's the deal... I have scenes that need to be rendered out to specific locations, with specific individual names (sprite sheet stuff - and thousands upon thousands of them). I'm using the software renderer from within Maya, because it needs to do things, like affect rotations, and build up the file name based on about 5 different things per frame - all unique, and not simple, sequential numberings.

After much struggle, I figured out that I could put the path and name in the defaultRenderGlobals.imagePrefix (or whatever it's called), and it will actually go where I want, and be named what I want. However, the script will not wait for one to finish before trying to fire off the next one, resulting in a lot of troubles, like skipped frames, and a continuous stream of popups asking if I want to cancel renders, or alerting me that renders are in progress. I've trekked through so many MEL files now, using whatIs to locate things, and following sometimes 30-40 function calls on the hunt for any info. The problem seems to be that batch rendering spawns a new process (seems to be a second Maya), and they communicate through sockets. I have no idea how to interface with that, and if I could, I wouldn't know what to do with the socket info.

I've also tried to set up the callbacks - all 6 of them - from the render globals window to act as a kind of callback, so I could have the script fire off once only, but also set up the post render stuff to kick it off again with new settings. Not even the preliminary steps of that concept worked, sadly. The callbacks seem never to happen. Perhaps they only happen when spawned from outside of Maya?

Is there any way to ask if batch rendering is in progress? I almost feel a render queue of some sort would solve this problem, but not being a render guy, I don't know anything about that. Thanks for any help.

[garyfixler]

Looks like the only way I'm going to be able to manage it is the way I just did. I.e. I use filetest -w file in a loop, with a pause -sec 2 in the loop to slow back on the disc hits, all to see when the file becomes writable again. It's working. As a safety net, I also put in a 120 second caveat. If timerX goes over that point, it fails out of the loop. So far, so good. It seems there's always a hackish workaround

Edit: I'm wrong. It still glitches every so many frames, asking me questions about if I want to cancel the render, and such. Anyone have any ideas? My next terrible attempt will be to query things about MayaRenderLog.txt.

Thanks.

[bill-beaumont]

Judging by the language you are using you are way out of my league in Maya, and I'm sure you've thought of this or tried them and they are not what you want, but have you searched on here for other batch rendering Mel scripts? They are bucket loads.

Even if they are not what you need, maybe you can reverse engineer them.

Dunno, I've never typed more than 12 words of Mel script in my life!

[garyfixler]

QUOTE(billbeaumon @ 06/14/08, 08:51 AM) [snapback]287075[/snapback]
Judging by the language you are using you are way out of my league in Maya, and I'm sure you've thought of this or tried them and they are not what you want, but have you searched on here for other batch rendering Mel scripts? They are bucket loads.

Even if they are not what you need, maybe you can reverse engineer them.

Dunno, I've never typed more than 12 words of Mel script in my life!

I hadn't actually checked for those, as I didn't know they were available. I will have a look. Thanks a lot!

[joojaa]

Well the thing is this is pretty easy do and to know. however dont do it in mel let the shell of your computer sort it out. Its the kind of basic computrer usage stuff thet we inherit form the "1970".*

Maya as allmost any computer program dwesigned for computation has a commandlien version. No a commandline is the perfect tool for this, because what it does i it launches a render (thats effectively what batch does too0), then returns back to the prompt for more commands. Now you can simply script them together by makeing a batch file wich is essentially just command stringed together.

So start by actually learning how to use the operating sytem of your computer. It provides a more easier to use functionality for this.

So examle for windows (if you use mac or linux chack the documentation on batching for your choice of shelll language) make a file that reads:

render -r mr -s 10 -e 20 -preRender("any needed init mel here") -cam persp file1
render -r mr -s 20 -e 129 -preRender("any needed init mel here") -cam persp2 file1
render -r mr -s 10 -e 20 -preRender("any needed init mel here") -cam persp file2
render -r mr -s 10 -e 20 -preRender("any needed init mel here") -cam persp file3
render -r mr -s 10 -e 20 -preRender("any needed init mel here") -cam persp file4
....

etc then execute it, you could make this a loop too but tahts overcourse.

anyway you can also call the render directly form within a system command, in mel wich gives mal the same kind of wait capacity. And calling batch render is doing exactly this but without asking for return.

This has alos a advantage, since its commandline you can spread teh task easily form one place to as many computers as you happen to have access to and have maya installed on them.'

*this si the kind of fundamental computing meny people skip out on that actually is the most valueble thing to know on ANY system yes even on mac. Sadly it takes 1 day to teach but years to explain the benefits for causla users. 3D users arent casual so they are expected to know this.

for me this is a bit sad since most modern computer users cant benefit of the most fundamental aspects of computing that all computer users in 70's 80's and very early 90's took for granted.