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booboo4ever
12-01-2006, 05:53 PM
hello all,

i am using maya 7.0 and trying to use the render layers for different passes.

as i understand it, if i make 3 different render layers (or more) and assign a different material to my object while any particular layer is highlighted, that material will be on the object when that layer renders.

i am doing quite a few passes, 6 to be exact. 5 of them come out as expected with the different materials assigned, but 1 always comes out with the wrong material. i do test renders of that layer to make sure the material is correct, but when i render a different material is put on to the object.

any clues? is this just end user error? did i miss something?

thanks for any help in advance

leigh
12-01-2006, 10:30 PM
Are you sure you haven't accidentally put an override on? Also, the Master Layer can act differently to other layers.

isoparmB
12-04-2006, 03:12 AM
Did you do apply any shaders on a per-face basis? I sometimes have problems with render layers losing their per-layer overides with polygonal objects with multiple shaders.

wabash
12-05-2006, 11:20 PM
Maya 7 renders layers are really cumbersome. They are unreliable when refrencing models. I've tried to use them on multiple occasions and on a good day it will keep all my shaders in tact on referenced models.
Anybody know if Maya 8 render layers are less buggy and don't randomly swap shaders?

acidream
12-06-2006, 12:38 AM
The render layers in maya 8 are definetely better than maya 7. It's way faster to switch between layers with lots of objects, and they added a "copy layer" which is pretty handy. I've been using render layers extensively for the past year on a show we've been working on, and I've never had it switch shaders once.

We do have a sporatic problem where when you switch render layers an pink error comes up that says something about the connection not being made between certain objects in your layer and the shader that was applied. Then the shader gets goofed up. It's really hard to reproduce, but we narrowed it down to certain nodes in the render layer that could not recieve shaders like constraints or components of a rig.

I think Maya is just real picky about what is in the render layer epecially when it comes to shader overrides. I've tried to be extra careful about what I put in there, like only geometry, no objects parented under other objects etc. and I can usually avoid the problem. As soon as that error comes up though the layer is screwed, so I will delete it and start over carefully watching what I put in. That's just my experience with the render layers.

Ironhalo
12-06-2006, 05:56 PM
we use maya 7.0.1 with render layers every day at my studio. ive never had any problems with render layer reliability. however, the only times ive gotten any goofy shader errors is when i assign specific shaders (ie a surface shader) to a layer and then change the shader in the master layer. sometimes i get an error with the assignment and the model goes to wireframe. i delete the bad layer and i'm fine again.

leigh
12-07-2006, 05:54 PM
we use maya 7.0.1 with render layers every day at my studio. ive never had any problems with render layer reliability. however, the only times ive gotten any goofy shader errors is when i assign specific shaders (ie a surface shader) to a layer and then change the shader in the master layer.

This has been my exact experience as well. I certainly wouldn't say the layers are unreliable at all, having used them on numerous productions, without experiencing any bugs. If something is going wrong, it's most likely the fault of the artist ;)

yenvalmar
12-08-2006, 06:50 AM
yeah, for not reading the mind of teh art director, marketing dept, etc who said to change the surface setting after the project was already putting shots through to post production :)

just wanted to mention i have had problems also, with changing the shader in the master layer once render layer shader over rides are assigned causing shader assignments in other render layers to screw up. fortunately its never caused me any huge headaches but i would consider it a bug.. and i feel i have always double check all the layers now before i do any renders, which is sometimes pretty time consuming in and of itself... but once everything is finalized the layers seem to remain stable.

one thing which saves me a bit of time is for a given shot i have an empty scene with my render layers and ambocc pass shader etc already set up, so whenever they get hosed i can delete them all, re import that scene and just re do the assignments, vs having to totally re do it.. or in the case of sequences with multiple shots using the same passes i dont have to re-do it for every shot..

wabash
12-08-2006, 04:30 PM
I disagree, leigh. I wouldn't say it's the fault of the artist, but the limitation of render layers. I suppose my difference in using render layers is that I have to used them (in many cases) with referenced models in a production pipeline. If there is any type of change to the reference model ie. a new piece of geometry this can affect the scene throughout the entire render pipeline. It's like the inital shader group hangs on is some cases frome the referenced scene.
If you are doing a production that doesn't require more than one artist and your scene is
clean and you have the flexability of deleting render layers if something in your master layer changes.....it's not a big deal, agreed. I've just had tons of headaches lighting/shading scenes before they are competly locked. I feel it would be very dangerous to suggest to any production that render layers (in maya 7) are reliable... one better have a back up plan and start saving out individual scene files for each render pass or importing referenced models once they are locked, but locked is a scary word to use, because scenes are never really locked before the project is wraped.

RavenEye
12-08-2006, 06:57 PM
Here I am looking for post on render layers issues and here I found one. Might as well chime in my two cents of issues, solutions(as I hunt them down), and possible work arounds.

The first issue I came across, before stumbling upon all the other errors that is plagueing this forum, is the shadow pass not working the way it should. I added my character and his light rig into its own layer, but when I rendered the shadow pass out every shadow render except for the objects with my skin shader. But the funny thing is, it only does that with certain shots, but for those certain shots it is always the same type of shader. This problem lead me to the other problems that everyone seems to be experiencing. My work around solution for the shadow pass not working was to create a shadow render layer with only a background shader on all of the geometry. Now things were working and people (I) were happy. Then the set had to be update, so I went along and updated the set. Then low and behold the problem with the render layers occured. I started getting this error, Error while parsing arguements. Poof all of my shaders lost their connection and all was left were the wireframes. And then on after it has and still is a constant problem, hense how I found this forum. I did find that deleting the problem layer or all the layers and rebuilding from scratch seemed to work until a reference file was upload. Sometimes I had to remove and reload the set reference and that worked some of the time. In a way I'm thinking it could be the multiple shaders on one piece of geometry, but it only gives me that error when I select more than one geometry with multiple shading network. Anywho, I am rambling on and I'm planning on doing some R & D work on a working workflow with render layers. Any suggestions on workflow is more than welcome.

Ironhalo
12-08-2006, 09:25 PM
i duno how much this will help, but i thought id post the workflow my house uses since i've never had any serious render layer problems.

we create an asset and texture it all in a single file. no render layers, just display layers. no lighting, etc.. if the asset needs to be rigged its also done here. from there, we create a new scene, reference all teh light rigs, cameras, assets and whatnot that we need. animation is then done in the referenced file. nothing more. from there, we begin adding in the render layers we need. if everything goes off fine and theres no changes (rare, i know) then i've experienced 100% reliability with render layers. we use muster to run the farm.

ive had scenarios where i cahnge textures in a render layer and assign a different one in the master next, this normally gives me the afore mentioned error.

hope that helps some..

leigh
12-10-2006, 11:19 AM
I disagree, leigh. I wouldn't say it's the fault of the artist, but the limitation of render layers. I suppose my difference in using render layers is that I have to used them (in many cases) with referenced models in a production pipeline. If there is any type of change to the reference model ie. a new piece of geometry this can affect the scene throughout the entire render pipeline. It's like the inital shader group hangs on is some cases frome the referenced scene.
If you are doing a production that doesn't require more than one artist and your scene is
clean and you have the flexability of deleting render layers if something in your master layer changes.....it's not a big deal, agreed. I've just had tons of headaches lighting/shading scenes before they are competly locked. I feel it would be very dangerous to suggest to any production that render layers (in maya 7) are reliable... one better have a back up plan and start saving out individual scene files for each render pass or importing referenced models once they are locked, but locked is a scary word to use, because scenes are never really locked before the project is wraped.

You're assuming that I haven't used them in production. I've used Maya's render layers on numerous feature films, with referenced models in pipelines which include many, many artists. And yet, no problems such as being discussed here - I am not referring to limitations of the system, but problems encountered such as wrong materials and such - those are far more likely to be due to errors by the artist instead of bugs in the software.

wabash
12-10-2006, 06:01 PM
Totally understood.
I suppose that just from my experience (or inexperience) if there isn't a standard to how referenced models are used and updated there can be issues with render layers loosing their assigned shaders. If an artist doesn't know the propper workflow of checking out the referenced file and making sure it's ready to be imported into a scene then divvied into render layers, then when referenced files gets updated...render layers get confused.
With your experience have your teams done something similar to what Ironhalo posted? Or have you actually never seen referenced models loose assigned shaders within their render layers?
When you say the fault of the artist, what exactly could that fault be when referenced models loose their assigned shaders within a production? What would be a good way to avoid this?
nice post ironhalo, thanks for sharing.

leigh
12-10-2006, 06:17 PM
Totally understood.
I suppose that just from my experience (or inexperience) if there isn't a standard to how referenced models are used and updated there can be issues with render layers loosing their assigned shaders. If an artist doesn't know the propper workflow of checking out the referenced file and making sure it's ready to be imported into a scene then divvied into render layers, then when referenced files gets updated...render layers get confused.
With your experience have your teams done something similar to what Ironhalo posted? Or have you actually never seen referenced models loose assigned shaders within their render layers?

Yes, we've used a system similar to what Ironhalo describes. I have never encountered the types of problems that you're talking about. Whether that was just luck, well I guess I'll never know. But I still use them regularly and find them incredibly useful and reliable.

When you say the fault of the artist, what exactly could that fault be when referenced models loose their assigned shaders within a production? What would be a good way to avoid this?

Please read both of my posts again. I am not talking about software bugs. I am talking about issues arising from an artists mistakes. If something goes missing, it's because somewhere, someone forgot to update something. Whether this is due to a breakdown in communication between the modeling and the lookdev/TD department, or simple absent-mindedness, the fact remains that if a model is updated, then it's up to someone to ensure that properties belonging to that asset are correctly updated too. The solution can be something as simple as a quick MEL script.

99.99999% of the "weird stuff" I've encountered in all my years of working with various software in production turned out to have perfectly normal explanations ;)

wabash
12-10-2006, 06:45 PM
I understand that your saying that issues arise from artists mistakes. I'm just trying to narrow down what those mistakes might be.

I'm not trying to pull teeth, but essentially what I've learned from ironhalo's post is that the asset should be textured before it is referenced in? If the model needs to be changed then the texturing should be re-done in that seperate scene and everything should be fine?

What I have done in the past is referenced in a model and began texturing it, then started to add render layers. I figured the render layers would just keep the assigned layers... because it keeps some of them when this issue arises. Though now I understand that there is a conflict with which shaders belong (the referenced in shaders, or the newly applied shaders in the render layers scene).

I would like to hear more about this. It wasn't my intention to rub you the wrong way leigh thanks for your help.

leigh
12-10-2006, 07:00 PM
I understand that your saying that issues arise from artists mistakes. I'm just trying to narrow down what those mistakes might be.

As I mentioned above, usually these can be chalked up to simple human error like forgetfulness or a breakdown in communication.

I'm not trying to pull teeth, but essentially what I've learned from ironhalo's post is that the asset should be textured before it is referenced in? If the model needs to be changed then the texturing should be re-done in that seperate scene and everything should be fine?

The asset doesn't necessarily need to have finished textures no, because it's referenced, and therefore updates with the latest info anyway. But yes, if something is updated, it should be done in that original file.

[quote]What I have done in the past is referenced in a model and began texturing it, then started to add render layers. I figured the render layers would just keep the assigned layers... because it keeps some of them when this issue arises. Though now I understand that there is a conflict with which shaders belong (the referenced in shaders, or the newly applied shaders in the render layers scene).

Well ideally the original referenced file should have the common shaders assigned to it (and common render layers). By common I mean the standard ones that it should always be rendered with. Additional render layers can be applied on a per-scene basis, depending on the TD's requirements for the lighting.

At the end of the day, communication between departments is the best way to ensure that hiccups do not occur.

I would like to hear more about this. It wasn't my intention to rub you the wrong way leigh thanks for your help.

Ermm I didn't feel rubbed the wrong way at all. I just felt I was repeating myself in my last post and wasn't sure why :)

wabash
12-10-2006, 10:29 PM
ok cool.
So in addition to texturing/shading an asset before it is referenced into a scene, you also have the standard render layers for that specific assest setup before it is referenced in as well.

So say you have a character and an environment as two seperate files. The character is one file with it's render layers and the environment contains it's own standard render layers. Once those two files are referenced into your master scene, the only remaining render layers you would add would be...say...the lighting passes for example.

I would be skeptical that the additional render layers added in the master scene would be reliable and hold their shader networks, but I'll give it a shot.

This has been helpful..continued thanks.

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