Import Only Materials From File

[brueggz]

Hi guys, I received a little task to prove my scripting skills.
The aim is to import materials from maya files to the actual scene, without importing anything but the materials.

I don't want to have script parts, only hints.
Is it possible to do this with the file-command? I didn't find a useful flag for that.
Or might python be useful for that (because i asked for a python task and it looks like a mel task).

On the other hand I could simply import everything from the scene and delete it, except the materials. But this would be very unefficient.

Thanks.

[gmask]

this is an odd task.. if you had an ascii file you could use python or perl to parse out just the materials, save those to seperate file and then import.. otherwise you'll have to import the file and delete everything but the parts you want to keep.. or perhaps you could reference the file duplicate the parts you want and then delete the reference

[brueggz]

Oh nice, I didn't know, that you can read the code to build the scene in maya ascii ^^.
So if the user choses a .mb file, the script would save it as a .ma and read out the materials.
Ok should work somehow. What about shadernetworks... I would filter which nodes are belonging to a material and search the connectAttr rows at the and of the file for the previously assigned materialnames.
The stored text will then be executed and there should be all the materials. (so far for the theoretic part, I'll see if it works in practice)
Would you agree with me?

[joojaa]

Its easier just to import all delete the nonmaterials.

[gmask]

QUOTE(Joojaa @ 07/13/09, 11:49 AM) [snapback]311482[/snapback]
Its easier just to import all delete the nonmaterials.

true .. especially if you are not loading the scene into an existing scene but I imagine this would be more useful if you could load it into an existing scene.

[joojaa]

Or one could use mayabatch to do it save out and load that? Just throwing out stupid ideas here.

[gmask]

QUOTE(Joojaa @ 07/13/09, 12:02 PM) [snapback]311488[/snapback]
Or one could use mayabatch to do it save out and load that? Just throwing out stupid ideas here.

guess that'd work

[joojaa]

Its actually easy to know what is newly loaded into the scene. So all you nee dto do is size(ls) at the before load and then only work on things that are at bigger ls index than that.

So maybe this could be easily accommodated. Wouldn't go into full prduction wuth this tough.

[gmask]

QUOTE(Joojaa @ 07/13/09, 12:23 PM) [snapback]311503[/snapback]
Its actually easy to know what is newly loaded into the scene. So all you nee dto do is size(ls) at the before load and then only work on things that are at bigger ls index than that.
So maybe this could be easily accommodated. Wouldn't go into full prduction wuth this tough.

Interesting.. well you could also pick the new stuff from a namespace which is what you'd want to do if you were importing into an existing scene.

[brueggz]

Thanks for the ideas so far.
Well, assuming the scene you want to import the materials from, would contain tons of polygons and the action would be saved in the history. I don't know, how much the import+delete action would mess up the RAM and maya history. Apart from the work to realise my last idea, which would you prefer... import+delete or clean import of only materials?

[gmask]

QUOTE(Brueggz @ 07/13/09, 02:00 PM) [snapback]311511[/snapback]
Thanks for the ideas so far.
Well, assuming the scene you want to import the materials from, would contain tons of polygons and the action would be saved in the history. I don't know, how much the import+delete action would mess up the RAM and maya history. Apart from the work to realise my last idea, which would you prefer... import+delete or clean import of only materials?

well using the batchrender with a prerender command idea of JooJaa's would allow you to do this seperately from the currently loaded scene.. it wouldn't have any impact on history just on memory usage.. I guess I'd say if the scene file size in small in binary format around 10-20MB's I'd just reference it adn duplicate what i wanted and then delete the reference. Anything over 50MB is going to be taxing to some degree

[brueggz]

1. Ok, I don't know if I understood this right... I call mayabatch, (with -preRenderCommand) create a reference of the user chosen scene, delete all nonmaterials, somehow remove the reference and then? Save the file temporary and the import it to my actual scene?!
   Sorry, I'm not as fast thinking as you

2. The mayabatch is the same as the batch renderer, right? Wouldn't it then render the empty scene and save this image to the project folder (maybe overwriting a former version)? Or is it possible to avoid rendering?

[rgkovach]

I wish maya had selective importing, like 3dsmax...

My workflow is to use EXPORT SELECTED on the stuff I want from the Source file and save it to a Temporary file.
Then I open my Destination File and Import the Temporary file.

Personally, I disable namespaces and allow maya to prefix conflicting nodes.

[joojaa]

QUOTE(rgkovach @ 07/14/09, 03:49 PM) [snapback]311559[/snapback]
I wish maya had selective importing, like 3dsmax...

Yes but unlike max mayas not rigid. So saying to maya load only materials wont work. Because maya truly does NOT know what things are materials. See the main problem is that the network maya sprawl in uncontrollable fashion. So its not clear to maya what would become imported, in worst case scenario the entire scene is one network thats connected together into one big mess.

So the critical part would be HOW maya chooses to diferentiate things. Ultimately nobody esle can decide this for you. Because they wont make the same generalisations as you would do.

So for example imagine a scene where each object is connected to a shading network trough a series of shading switches. Now what happens is that everything in the scene is one block because in order to load the materiasl it needs all shapes as well. Leading to whole scene load. (worse the sece contains a script node that deals with connections to the switch node and its NOT part of the network and you want it)

So now the problem is that i could want to get the entire network up to the shading switch but no further. But then again i might not. So who can decide this for me?

In any case makeing a selective load yourself is NOT really a impossible task i outlined it for you.

[gmask]

QUOTE(rgkovach @ 07/14/09, 04:49 AM) [snapback]311559[/snapback]
I wish maya had selective importing, like 3dsmax...

QUOTE(rgkovach @ 07/14/09, 04:49 AM) [snapback]311559[/snapback]
My workflow is to use EXPORT SELECTED on the stuff I want from the Source file and save it to a Temporary file.
Then I open my Destination File and Import the Temporary file.

Well I think the OP's idea is that you have a scene open that you want to copy the shaders from so you'd have to open another instance of maya to do it your way which isn't really a problem unless you only have 2GB of ram or something.

At any rate there's not really any way to get aroudn having to read into memory the entire maya file so that you can parse out or otherwise export just elements you want. If you were working with an acsii file then you might beable to scan the file line by line and pick out elements you needed in a low memory situation but it would probably be extremely slow.

QUOTE(rgkovach @ 07/14/09, 04:49 AM) [snapback]311559[/snapback]
Personally, I disable namespaces and allow maya to prefix conflicting nodes.

That's really a bad habit to find acceptable.. it's fine if you are just working on small elements and you clean up the mess afterwards but in larger pipelines this would be totally unacceptable because it only complicates any kind of automation.. you might as well tell maya you don't care how screwed up the names become and to name them almost randomly... give a monkey a loaded handgun while you're at it as well.

Here's a reason as to why you should use namespace... in a best case scenario there should never be two nodes in a scenefile that are named the same. Even though they may not appear to conflict because they are nested in a hierarchy they simply become troublesome when you have to specify absolute paths because of this. Now in a script you should allways use full paths but for human readability you don't want to be forced to deal with fullpaths all the time. So if you have maya only occasionally prefixing conflicts you'll have no conistancy and you'll still have nodes buried in hieracrhies that are not unique.

In a larger pipeline if you are referencing a few or more copies of the same file and you use namespacing properly it insures that this will not happen. Therefore if you want to select the foot bone of character3 then all you'd have to type is select character3:foot instead of select |character3|root|hip|thigh|shin|foot or select character3:root|character3:hip|character3:thigh|character3:shin|character3:foot

[rgkovach]

Its a double-edged sword. I appreciate Maya's flexibility and its agnostic relationship with nodes.
But Maya's generalized approach often frustrates "less-techy" artists because of "seemingly" simple features, such as selective importing.

It just means that I have to use Mel to funnel data so it looks like Maya is doing what an end user wants, and thanks to Maya I can!

[joojaa]

Yes but on wich edge would you like to be is the question? So do we really need to bother with the ones that donet want to be part of the bother? (they dont NEED to use maya) Which s better

Being able to do what you need

Or just do what you are allowed to do

Which brings in money? Please note even the very confined solution has holes in it and has "easy to do" things taht cant be done. You cant get away form them.

[rgkovach]

I wish I could just wave a wand and make all my Max-loving artists dissppear!
Or at least wave a wand and make them understand maya better....sigh...

[joojaa]

QUOTE(rgkovach @ 07/15/09, 04:53 PM) [snapback]311640[/snapback]
I wish I could just wave a wand and make all my Max-loving artists dissppear!

Yes but when they come saying to you in need this because max had this wonderful tool. Remind them that its exchange of things. You can illuminate it like this:

You know your a cool person, and the boss is like all bosses a bit alof and often stupid. If you wree the boss you do a lot of things differently. But you'd be in reality equally stupid, youd only do differnet things wrong and thus the end recipe is different but just as bad for everybody esle.

So tell them not to stare at the half empty glass but the half full one. Ask them do you really mean theres nothing good about maya? If they cant find anything then MAYBE, its time for them to look for work elsewhere.

Working in different app surprisingly means working different (for those of you who see this as self evident, lucky you). If they were same what would be the point.

[gmask]

QUOTE(rgkovach @ 07/15/09, 05:53 AM) [snapback]311640[/snapback]
I wish I could just wave a wand and make all my Max-loving artists dissppear!
Or at least wave a wand and make them understand maya better....sigh...

well all programs have theirs pros and cons.. I have heard alot lately about how well or better Max handles textures libraries and honestly it is an area where maya is very weak especially when you have alot of textures or render layers.. it sucks.

However from a pipeline point of view I don't understand why you'd need to import the textures from another file that often.. why not do it once and save it too a separate file but otherwise I understand what it's like to have to support seemingly arbitrary requests and I don't really have a problem with that.. it makes me smile when they are happy.