Maya Chan Exporter

[darcel]

Thank you guys, for answering my question, I must of did the procedure incorrectly. My next question is what format does Nuke understand once you export the data? I notice that it gives you options to export to .ma, .mb, .obj, .dxf, will it have to be opened in a text editor?

[user_deleted]

not sure if I understand correctly but the mel script exports chan files which is what Nuke needs.
it's a simple text file with one line per frame formatted like this:

frame tx ty tz rx ry rz fovv

if it's an object chan file there won't be a fov.

[darcel]

Thank you Frank,

yeah it works, however when it asks were to save it doesnt give me the option of saving as .txt file. Its probably me doing something wrong again.

[user_deleted]

I can't remember what the file browser was like and from looking at the mel script it doesn't seem to use suffix filtering which might be where the confusion is. Can't you just type something like myOutput.chan as a file name and hit save (ignore any file format options)?

you should see something like "Exporting to " followed by your file name in the mel terminal is you do it right.

sorry, without a maya here I can only guess.

[darcel]

Yep, that was it! Thank you Frank. Big fan of your work too!

[user_deleted]

no worries, glad I could help

[darcel]

Hey Frank or anyone who might know this,

What settings do I need to change once I've imported the .chan file in from Maya? Do I need to match the camera settings that Maya was working with or does Nuke do this for you automatically? The reason I ask is becuase I'm trying to match talent into a virtual set done in maya. I'm getting the best results in Nuke other than in Shake or After Effects. The one issue would be the focal length, Hor, Vert, film aperature etc... that doesn't match. Any tips?

[lebedev2]

You will need to adjust the settings in Nukes camera to match Maya's camera, all that comes into Nuke is translation, rotation and FOV (unless I am animating the FOV I just usually input this manually into NUKE . Maya's camera aperture is in inches while Nukes in is MM so what you do is you take Maya's h and v aperture and covert the inches to mm and input it that result into Nuke's H and V aperture. You need to also make sure that your Maya's film aspect ratio is set correctly in Maya. I set my rotation order to xyz and all works great.

Jordan

[darcel]

sl0throp,

That was it! Thank you very much for the tip. When I set my cameras rotaion to xyz, it all came together. Also I went under my Maya prefs and found out that by default (v8.5) Maya works in centimeters and not inches when I changed my scene to inches the camera also changed, so instead I converted my centimeters to milimeters and it worked. But does that sound correct to you? Does the Maya camera work in inches while Maya's world coordinates are at centimeters, or does it apply to the entire scene?

[user_deleted]

why do you need a txt suffix?

[darcel]

Sorry, I needed to add the .chan extension to the end instead of the .txt as I mentioned before. Still learning but loving it more and more each day!

[user_deleted]

hi guys,

i'm playing with nuke for a couple of days now and i'm beginning to like it very much. But i still just can't get the mel script to work! i've placed it just about everywhere /Users/rio/Library/Preferences/Autodesk/maya/8.5/scripts and such with no avail. i keep getting "// Error: Cannot find procedure "exportcamchan"." I dont know whats happening. on my windows box i get the same error message.

i hope someone can help me so i can enjoy nuke even more:)

cheers!

[user_deleted]

in the mel script editor source the file first, to make sure it's known:
source "<full_script_path";

then make sure you get lower and upper case right.
"exportCamChan" should work. Also "importCamChan" and "exportObjChan" are amongst the i/o modules in that script.

If unsure about the spelling look at the mel script in a text editor and you should find the above mentioned commands.

cheers,
frank

[user_deleted]

Thanks Frank,

The source thing did the trick
But, do i have to source it every time i want to use the script?

[user_deleted]

That would depend on how you set up Maya. I'm not a Maya artist so I can't really help you there but I'm sure there is a default location where you can put the script so you don't have to source it manually all the time.
Does anybody know?

[ior]

QUOTE(rueter @ 04/24/07, 01:48 PM) [snapback]264793[/snapback]
That would depend on how you set up Maya. I'm not a Maya artist so I can't really help you there but I'm sure there is a default location where you can put the script so you don't have to source it manually all the time.
Does anybody know?

You can source it in your userSetup.mel file.

[darcel]

...I also like to store them to my shelves, that way its just a matter of click and save.

[dunkel3d]

if you install a new mel script while maya is open you must type rehash; to reread all the script present in the script folder.

then you have to source the script doing source scriptname.mel then you can finally run all the procedure you can find in the script!
hope this help.

Mat

QUOTE(darcel @ 04/27/07, 01:53 PM) [snapback]265050[/snapback]
...I also like to store them to my shelves, that way its just a matter of click and save.

[mloomis]

Has anyone had any problems with the accuracy of the chan camera files once in nuke?

[thedott]

I'd use my pass2nuke.mel script that's part of MoCon, stuck on the board today as a d/l. Exporting just the chan data can open a big can of worms and lead to user error easily. Instead, my pass2nuke script writes out a Nuke script. It adds a camera, and object transform nodes all connected to a scene node in Nuke. The camera is set to the same film back as what's in Maya. The rotation orders are also preserved, so you won't run into those issues either.

Barry Berman
3Dmation Visual Effects