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Philbert
12-09-2015, 10:56 PM
I'm being asked to take over a project from someone else who had to stop working on it. I was sent an animated scene from maya that has a couple of characters and vehicles moving around a little. Nothing really major. I have a copy of the latest maya here so I opened it and exported to FBX. When I try to load the FBX in Layout it starts working then freezes. The folder created looks like it probably exported everything, over 650 objects, and I can load the scene file from the folder after restarting Layout but everything is kind of scattered around. Any tips for moving from maya to LW?

cyroz
12-09-2015, 11:42 PM
I had a similar problem, involving maya - modo and lightwave, the best way I found was using alembic files.
The animations of the characters will be cached, so you won't have rig to modify them...

Philbert
12-09-2015, 11:44 PM
I'll have to look at how to export that from maya. I guess it's pretty much the same as exporting FBX.

Philbert
12-10-2015, 12:20 AM
Hmm Well I got it imported. I'm not sure if it's better or worse. lol It seems to be in the correct positions except the characters are not there and there are no textures, everything's just white, well 200,200,200.

DCjr
12-10-2015, 01:23 AM
You should have options for exporting in Maya. Are you using Maya 2015 0r 2016? There are preset options when you export.

I go back and forth between Maya and Lightwave all the time. I really like the free form modeling in Maya. I model in the perspective port and use the split poly tool often. I really feel like I have good control of manipulating the mesh as I model. The fall off effect for use with modeling is nice too. Its very visual.

Philbert
12-10-2015, 01:25 AM
Version 2016. I found the alembic option, it's actually listed under the Cache menu instead of Export.

DCjr
12-10-2015, 01:27 AM
So you're not getting textures on export. I wonder if alembic is broken with 2016. I'm using 2015.

Philbert
12-10-2015, 01:28 AM
Oh with FBX I was getting some textures, they just needed tweaking. It's with Alembic that I get no textures.

Surrealist.
12-10-2015, 12:55 PM
As far as I know that is normal. If you are only rendering the workflow is to set up all of your textures and shading in the target. I have read that Alembic got texture support, but I don't see the option in Maya and when I export It comes across with UVs. But if you have multiple objects go to the advanced section and choose Write UVs or the UVs get jacked. (Well at least to Houdini they did) It might be different in Maya 2016 though.


If you are going to continue to animate in LW though Alembic might not be the thing. Also if you are exporting in FBX and having issues, try exporting only sections of the scene at a time.

Philbert
12-10-2015, 01:09 PM
Yeah, I exported the environment alone as FBX and some parts are out of position but I think I can just look at the maya scene and get them back where they're supposed to be. Then I can probably do the same with the vehicles. The characters I'll probably just start over since they don't seem to be transferring at all. Luckily it's just simple movements. Hopefully it's not too much work. Thanks.

djwaterman
12-10-2015, 06:14 PM
I go back and forth between Maya and Lightwave all the time. I really like the free form modeling in Maya. I model in the perspective port and use the split poly tool often. I really feel like I have good control of manipulating the mesh as I model. The fall off effect for use with modeling is nice too. Its very visual.


Any plans for detailing your process for moving things back and forth between Maya and LW, with all the talk from LWG about this ability they haven't really put out a good tutorial on how to do it.

Greenlaw
12-11-2015, 11:07 AM
Just thinking out loud but I wonder if everything needs to have at least one key frame before exporting to FBX? I don't think I've come across this problem before so I'm not sure.

Philbert
12-11-2015, 12:03 PM
I don't think so since I can export still objects as FBX, like a character form Make Human.

Greenlaw
12-11-2015, 12:06 PM
Ok. I just though explicitly keyframing the items, whether they need it or not, would fix their positions for export. Basically baking them, in other words.

Farhad_azer
12-11-2015, 12:23 PM
I have recently met a Maya artist and talked to him about LW, so I like djwaterman am interested to find out more about details.

Would you please write your conclusion and difficulties of the process when you are done? Thank you.

Philbert
12-11-2015, 12:32 PM
Oh I see what you mean Greenlaw.

OK Farhad.

Greenlaw
12-11-2015, 02:45 PM
I had to recently bake out several Maya (2013) scenes to LightWave 2015.3. I mainly used FBX and Geometry Cache (Maya's version of MDD.)

For the camera, I had to first bake out the keys. I used Edit - Keys - Bake Simulation for that. Then I made sure the camera was selected and used File - Export - Selection and set my format to FBX (2013.1).

For stationary elements, I selected what I wanted and used the same export command.

To import to Layout, I just used Load Items From Scene and selected the FBX files.

For the characters, I first selected the meshes and saved out OBJ files for each character. Use the same export command but select OBJ as your file format.

These can be loaded into Layout like .lwo objects. It may not be necessary but I like to save them as .lwo so I can save Lightwave surface properties to the meshes.

For the character animation, I selected a character's mesh and used Geometry Cache - Create Geometry Cache to save out a cache file. I think I just used the default settings.

In LightWave, select the mesh and add MD_Reader to the mesh. Next, load the geo cache file like you would an MDD file.

That's pretty much it. Or at least, it should be that easy. Sometimes Maya would crash on me when creating the geo cache file but usually this happened a the end and the file would be okay for Layout.

I think the main thing is to make sure every frame is baked before exporting. This is why I asked earlier if the stationary objects had at least one keyframe applied. I don't know if it's really necessary but just a guess.

G.

Edit: There may be an easier workflow. This is just what worked for me recently.

vector
12-11-2015, 10:17 PM
As Greenlaw says, if you are going to use repeatedly chars in different scenes, you should use the char's as lwo and loading mdd to keep textures and shaders.

Surrealist.
12-12-2015, 03:51 AM
It depends on if you are going to continue on with Maya or not I suppose. Usually the workflow is to LightWave with animated assets. And since FBX brings along bones you don't need along with potential other issues, usually related to constraints etc., the most fluent solution I know of is mdd. I did that workflow for a client and it worked a dandy. :)

However it does come with a caveat, and that is you are stuck with the scale from Maya. One workaround for that is to create an additive animation layer in Maya and scale the rig down by .01. Then do your exporting.

Scale note:

A "unit" in LightWave is treated as a Meter. Exporters and importers seem to talk only in "units".

So if Maya default 1 unit = cm is used then those units would get blown up by 100 when imported into LightWave, since LightWave default unit is a Meter.

If you will notice the scale parameter on FBX import in LightWave is set to a default of 1. I do believe, if memory serves, that this is to be construed as an integer number as in 1= 1 percent of 100. So the default FBX import automatically scales to .01 or 1 100th.

When using .mdd you no longer have this option so it has to be scaled in Maya.

Greenlaw
12-12-2015, 12:13 PM
Or you could just scale down the mesh with MDD or Geo Cache applied. To do this, need to set MD_Reader from World Space to Object Space (or Local if you're using a different MDD reader.) If there's multiple meshes, you could parent them to a null and scale the null--but you must be in Object Space for this to work. (Using a null can also work as a different pivot point from the MDD's fixed world center.)

There is a catch though: I discovered a long time ago that scaling the MDD down can do weird stuff with dynamics and FiberFX. To work around this, you'll need to rescan a new MDD after the scaling and get a 'properly sized' MDD for your scene. Then you replace the Maya Geo Cache with the scaled LightWave MDD file. Now, as far as LW is concerned, the scale of the MDD is 100%, not 1% or whatever. Of course, if you're not having dynamics or FiberFX problems from scaling, you can skip this extra step.

G.

DCjr
12-12-2015, 08:34 PM
Any plans for detailing your process for moving things back and forth between Maya and LW, with all the talk from LWG about this ability they haven't really put out a good tutorial on how to do it.

Oh sure, I can try and break down my process.( I missed this message)

Surrealist.
12-13-2015, 01:30 AM
Or you could just scale down the mesh with MDD or Geo Cache applied. To do this, need to set MD_Reader from World Space to Object Space (or Local if you're using a different MDD reader.) If there's multiple meshes, you could parent them to a null and scale the null--but you must be in Object Space for this to work. (Using a null can also work as a different pivot point from the MDD's fixed world center.)

There is a catch though: I discovered a long time ago that scaling the MDD down can do weird stuff with dynamics and FiberFX. To work around this, you'll need to rescan a new MDD after the scaling and get a 'properly sized' MDD for your scene. Then you replace the Maya Geo Cache with the scaled LightWave MDD file. Now, as far as LW is concerned, the scale of the MDD is 100%, not 1% or whatever. Of course, if you're not having dynamics or FiberFX problems from scaling, you can skip this extra step.

G.

Great tip, thanks! Though if I am doing this, scaling before hand makes much more sense and less work in LW.

Also I have found just as a general 3D rule avoid scaling at the object level. There are numerous unforeseen issues that certain tools have with a mesh that is scaled and freezing scaled objects is always a good idea before moving them down the pipeline in any way. And this is in effect what exporting geo cache or Alembic does when you export.

And as you point out with some tools, the scaling messes with them. So then you have to in essence freeze the cache file.

Just for me, I like keeping things clean all through so yo don't have to mess with any unforeseen issues.

Greenlaw
12-13-2015, 02:17 AM
Yes, you're right of course--ideally, the scale should already be what you need in LightWave on import.

Most of the time, however, I have little control over how the Maya files are setup and animated, and that's when being able correct the scale properly for LightWave within LightWave becomes necessary. Fortunately, this is pretty easy to do.

G.

Surrealist.
12-13-2015, 04:33 AM
Yeah good point. I am completely disregarding that scenario in which case , yeah, good to know. And again thanks for that tip. It had stumped me before. :)