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dblincoe
07-25-2011, 01:47 PM
Hi all! Was wondering if the community could share how they go about breaking up larger scenes into smaller ones for multi-pass rendering?

I have exrtrader and am very pleased. But I'm not talking about just separating buffer passes. I'm talking about separating objects out, etc. I will be using the depth buffer to help composite these layers back together. My problem is mainly, the size and scope of the scene and breaking it up into manageable rendering sections for compositing later.

I know of passport and Jannus, but passport I believe is dead and Jannus is not mac friendly. Any others?

Thanks in advance to all of you helpful people!
Dan

nickdigital
07-25-2011, 01:53 PM
Bite the bullet and just go through the tedious process of making separate lws files.

Render pass management is something that every seasoned LW'ver has moaned and groaned about. So welcome to the club. :D

dblincoe
07-25-2011, 01:59 PM
Bite the bullet and just go through the tedious process of making separate lws files.

Render pass management is something that every seasoned LW'ver has moaned and groaned about. So welcome to the club. :D

I was afraid of that...but appreciate your honesty! Sometimes it is better in the end anyway. Automation can sometimes have some nasty surprises later.

Thanks!

dblincoe
07-25-2011, 02:03 PM
Bite the bullet and just go through the tedious process of making separate lws files.

Render pass management is something that every seasoned LW'ver has moaned and groaned about. So welcome to the club. :D

BTW: Impressive reel! Does Nickelodeon us LW a lot?

Cageman
07-25-2011, 02:08 PM
I've been using Janus a lot. A pretty darn neato addition to LW.

http://faulknermano.com/janus/overview.html

:)

dblincoe
07-25-2011, 02:20 PM
I've been using Janus a lot. A pretty darn neato addition to LW.

http://faulknermano.com/janus/overview.html

:)

Wish it was stable on Mac

Greenlaw
07-25-2011, 02:23 PM
Yeah, Janus is probably the best 'automated' system available now. If you don't have that, it's time pay your dues as a LW user. :)

At work we used to have an in-house passes system but it broke during the 9.6 beta and it was abandoned until things looked more stable for LW.

FWIW, these days we're finding it less necessary to break out as many separate scene files as we used to, thanks to Object and Material IDs. When we need to output custom masks or elements, we try to optimize by rendering multiple elements to different channels. For example, a common combination for us is MTE or mouth, teeth and eyes. For our MTE pass we will render the mouth mask as red, teeth as blue, and eyes as green, and the alpha is set aside for anything else that might be useful in comp (maybe facial hair, eyebrows, glasses or a hat?) In other words, in many cases, it's possible to get multiple elements from a single LW render.

One plug-in that really helps us is an in-house tool for automatically synchronizing the camera for all the passes in a shot (works with LW scenes only though.) IMO, Lightwave really needs to have something like this built in.

G.

dblincoe
07-25-2011, 02:26 PM
One plug-in that really helps us is an in-house tool for automatically synchronizing the camera for all the passes in a shot (works with LW scenes only though.) IMO, Lightwave really needs to have something like this built in.

G.

Not sure I follow...if you are rendering passes in one scene aren't you using the same camera?

nickdigital
07-25-2011, 02:27 PM
BTW: Impressive reel! Does Nickelodeon us LW a lot?

Thx! :D

My group does. The other dept that is responsible for the for the CG shows like Penguins, Fanboy, etc use Maya.

dblincoe
07-25-2011, 02:27 PM
Thx! :D

My group does. The other dept that is responsible for the for the CG shows like Penguins, Fanboy, etc use Maya.

Cool! Great work!

nickdigital
07-25-2011, 02:30 PM
Not sure I follow...if you are rendering passes in one scene aren't you using the same camera?

I believe Greenlaw is talking about using a tool that syncs the camera between different separate lws files. I may be wrong though and he should correct me.

Using a script like MultiMotionGN might help with making sure all your separate lws passes are in sync. It's a utility to batch save/load motion files.
http://thespread.faulknermano.com/_theoldspread/index.htm

If you have Jeremy Hardin's Reference motion script that would be another option. It'll save out the motion file every time you save your scene. You then setup a reference scene that will load the motions every time you load it.

dblincoe
07-25-2011, 02:42 PM
I see. That makes sense. If you change your camera in your master, then the script could update the cameras in the pass scenes.

I'll take a look at those scripts. Thanks!

Greenlaw
07-25-2011, 02:57 PM
That's correct. Camera syncing is useful when changes to a shot are requested, especially if the changes involve the camera. This way, we only need to update our master camera file, and all the shot passes get updated, saving us from manually updating the camera in every pass.

Before we got our camera syncing tool, we saw way too many mistakes happen on the farm, especially when several guys were working on the same shot. Automatic camera syncing eliminated that part of the problem. I know at times we've had as many as 80 cg passes in a shot...imagine manually updating the camera for all those scenes!

BTW, MultiMotion is especially useful for updating animation on Lightwave character rigs. It's not automatic like the described camera tool, but it certainly can make life easier when updating CA in many 'breakout' scenes. An even better solution, however, is to write out an .mdd file for a shot. This is a little more like our camera syncing tool, at least in practice (i.e., a single data file referenced by the same character in all 'breakout' scenes.)

Hope this helps.

G.

Cageman
07-25-2011, 03:00 PM
This is a little more like our camera syncing tool, at least in practice (i.e., a single data file referenced by the same character in all 'breakout' scenes.)

Hope this helps.

G.

Out of curiosity... does this tool transfer all camera attributes or just a select few?

dblincoe
07-25-2011, 03:17 PM
BTW, MultiMotion is especially useful for updating animation on Lightwave character rigs. It's not automatic like the described camera tool, but it certainly can make life easier when updating CA in many 'breakout' scenes. An even better solution, however, is to write out an .mdd file for a shot. This is a little more like our camera syncing tool, at least in practice (i.e., a single data file referenced by the same character in all 'breakout' scenes.)

Hope this helps.

G.

.MDD - another format that I haven't had the option of pursuing while at my previous employer. Now that I'm out on my own I am catching up and learning all of these new technologies and workflow's. Can you write a mdd file for a whole scene? Or is it object at a time? Thanks for sharing! I feel like I'm starting over again.

nickdigital
07-25-2011, 03:22 PM
MDDs are per object. You can think of them as the equivalent of pfx or bdd files for particles and dynamics.

But MDDs can be read by other packages too. It's a very stable way of transferring deformation data between other programs. LW10 also has GeoCache if you're in a Maya pipeline.

jasonwestmas
07-25-2011, 03:57 PM
Automation can sometimes have some nasty surprises later.



I think in this case though, Automation (Janus) is key for better success. Kind of like how hard body simulations for a collapsing structure or a particle emitter for smoke is automatically more successful than doing it by hand.

Cageman
07-25-2011, 04:19 PM
Automation isn't really a good description for it. You are in 100% control... the good thing with Janus is that it uses a propagation methology, which means that you litterally are applying settings to groups. What these groups contains are up to the user, not Janus. So, if you setup a project to use Janus, you can reuse ALL settings on a completly different project.

Essentially, I might have spent 1 day setting up one shot in Janus, and double and tripple check that everything works when I bring it togheter in comp.

The rest of the 83 shots will take about 5-10 minutes to setup and get ready to render because I reuse all the groups and passes from the original setup.

Next project... sure... if I keep using a similar structure to the scenefiles, I can reuse the settings from the previous project and be up and running in no-time.

Janus should be viewed as a long term investment for a serious renderingpipeline. Yes, it does take time and practise to understand it and get fast with it, but the investment in it will save you tons of time down the road.

:)

nickdigital
07-25-2011, 04:21 PM
Automation isn't really a good description for it. You are in 100% control... the good thing with Janus is that it uses a propagation methology, which means that you litterally are applying settings to groups. What these groups contains are up to the user, not Janus. So, if you setup a project to use Janus, you can reuse ALL settings on a completly different project.

Essentially, I might have spent 1 day setting up one shot in Janus, and double and tripple check that everything works when I bring it togheter in comp.

The rest of the 83 shots will take about 5-10 minutes to setup and get ready to render because I reuse all the groups and passes from the original setup.

Next project... sure... if I keep using a similar structure to the scenefiles, I can reuse the settings from the previous project and be up and running in no-time.

Janus should be viewed as a long term investment for a serious renderingpipeline. Yes, it does take time and practise to understand it and get fast with it, but the investment in it will save you tons of time down the road.

:)

Does Janus work with UNC paths?

jasonwestmas
07-25-2011, 04:28 PM
Yes, that's a good way to put it Cageman, creating groups of passes and reusing pass settings etc.

Cageman
07-25-2011, 04:34 PM
Does Janus work with UNC paths?

I havn't tried. At work we use mapped drives and at home I do the same.

:)

I used to run UNC paths waay back, and during that time I stumbled across some third party tools in LW that didn't work well with UNC. Those tools, that were object replacement tools, kind of, were too important for my workflow, so I changed to use mapped drives.

Are you running UNC? If so, have you tried Janus to see if it works?

nickdigital
07-25-2011, 04:52 PM
Are you running UNC? If so, have you tried Janus to see if it works?

Yes and Janus wasn't working for us. Matt's update to Passport is borking on me too so I wonder if this is a UNC issue. Though I couldn't get Passport to work with a mapped drive too.

dblincoe
07-25-2011, 04:56 PM
Yes and Janus wasn't working for us. Matt's update to Passport is borking on me too so I wonder if this is a UNC issue. Though I couldn't get Passport to work with a mapped drive too.

I can't even get passport started. Not sure what is going on. I was going to give it a try but no joy. I saw a couple of threads where the development seems to have been handed off. Hoping someone get's it figured out.

dblincoe
07-25-2011, 04:59 PM
Thanks again for all the useful tidbits, guys! I'm glad to be on my own boss now and able to invest in learning these new technologies (and the old the ones I missed out on).

Greenlaw
07-25-2011, 05:11 PM
Out of curiosity... does this tool transfer all camera attributes or just a select few?
I believe it's just lens and motion, not camera type, etc. Basically, it checks a Master Camera scene for camera data when you open a scene, and there is a button to force an update (synchronize) in the tool panel.

This tool worked well when we dealt only with LW scenes but things started messing up when we began exporting Lightwave camera scenes direclty out of Maya because certain camera properties were being set by our camera exporter that we didn't want into the scenes. I think right now we're just using FBX from Maya and then manually converting that into our Lightwave Master Camera scene.

Actually, I'm not 100% sure what our workflow is at the moment. Our workflow has been in a state of change because various programs are being updated. (Always happens around Siggraph time.) Everything I just wrote might be completely different in a few weeks. :)

Greenlaw
07-25-2011, 05:17 PM
I should have added that we have to bake the camera in world space in our Master Camera scene for this to work reliably. I believe the tool will technically work with a rigged camera that doesn't have baked keys but that turned out to be risky in some situations.