Xgen bugs

[Anonymous]

Hello,

I am working with Xgen and have thoroughly enjoyed the process of working with hair, but have encountered so many issues that I don't know if they are repairable. If anyone has advice, I would greatly appreciate it. I have had unfortunate luck with finding any communication on forums for the issues I have encountered. If this is the wrong place, please direct me.

Prior to all of my problems, this is the groom for my character (wip):

Needs a lot of work, but it has been a great experience. However, as of two days ago these issues started happening:

1. I am no longer able to render in my render view. In my script editor after clicking render or refreshing an IPR it states: "Exporting Xgen Collections . . . Done"

2. My groomable splines are now 'exploding' as I preview the description and the often crash. I have attached an image for visual explanation:

Although I enjoy glitch art, this is my nightmare. It seems to be my modifiers that have gone haywire. As I begin to hide them there is a visual difference in the Kandinsky painting I receive.

My set up for the hair has been two collections:

 Scalp: overall hair (groomable spline), groom (spline), stragglers (spline)

 Eyebrow: overall (groomable spline), groom (spline)

I have been having issues for several days now - last night it was working - today is a different case. I believe all of my issues started occuring when either:

A- I added the second groomable spline description to the eyebrow collection.

B- I redirected the grooming auto export to the desktop on accident. I have since reconnected it to the project file.

C- I created a new project folder and copy/paste the scene and xgen collection, and copy/paste the xgen folder. I was working on a network rather than my direct drive and was curious if my system was lagging.

I have officially hit my wall of tolerance with Xgen and am sending out my SOS. Please help with any information.

Thank you,

Justin

[Anonymous]

Hello Everyone,

I just want to update this last post. I ended up looking through all of the information Autodesk has for Xgen. For whatever reason my searches never let me find it before. However, they are a huge help and I have restarted my character's hair with this new information.

I still do not know exactly what happened wrong, but assume it was my redirecting the autoexport. I still have concerns about saving and exporting collections/descriptions. So if anyone has any pointers on that I would appreciate it. I have read quite a bit, but still need clarification.

I understand what a description exports, but does a collection export the description as well (hiearchy)? And do I need to save anything within the Xgen window if I am closing out of Maya? ie collection, description, modifiers, grooming (for groomables)?

Here is an update on the new hair system:

Justin

[pshwayka]

Hi Justin,

Glad to see you're back on track...I read your original post yesterday, and was pretty much baffled. BTW, your model's hair is looking great.

As for your questions, when you save your scene the collections and descriptions should automatically get saved in the original location you specified when you first created them. Also, if you choose to export your collection as a backup, it will automatically include the descriptions. 

Also, just curious...is that RHEL you're running or is it Fedora? And does Maya run well on it?

[Anonymous]

Hi pshwayka,

Thank you for the compliment and the response. I still have not found the reasoning for what's happening. I do know it may have something to do with my network and groomable splines. 

It is RHEL OS. I have never worked with Fedora so cannot compare the two, but can compare working on the same project back and forth from Windows. In my personal experience there is a slight difference favoring towards Linux but that's without recognizing the possibility of running several programs at once. Command line rendering is the main difference but I barely use it because I send renders to a renderfarm on location. I know that's not the most helpful answer; I will say in favor of a lot of my friends/colleagues they swear by RHEL over Windows for Houdini and Maya. No Zbrush compatibility as far as I know though.

[Anonymous]

Hi Justin

I just came across your discussions regarding xgen freaking out, I too am experiencing those weird colour shapes and cant understand why they are appearing. 

My scene:

• Im currently creating a field of grass, I've started by making one collection with 3 discriptions. 1 description controls the static grass and the other 2 the colidable grass. 
• Im using a animWire modifire with the hair system to control the colision and flow of the coliding grass
• Everything was going great and I finally got the grass to react in a way I was happy with
• When I shifted back to the static grass discription that is when all hell broke loose

You mention that you came across some imformation that showed you how to work around that? Could you please be so kind to share that info via a link?

King Regards

Faghrie

[Anonymous]

adding on to my above comment:

Justins comments vs Mine:

A- I added the second groomable spline description to the eyebrow collection.  (I added 3 groomable descriptions to my collection and they all diplayed find and I was able to groom them without problems)

B- I redirected the grooming auto export to the desktop on accident. I have since reconnected it to the project file. (my scene has been living on the network ever since I created the project, I never moved it around at all )

C- I created a new project folder and copy/paste the scene and xgen collection, and copy/paste the xgen folder. I was working on a network rather than my direct drive and was curious if my system was lagging. (again, my project was always in one location)

With that said, it seems that neither of the things you did above could of caused it to perform that way since I didnt do any of the stuff you mentioned leaving me to assume that there is another reason?

I came across my problem after I had added a animWire modifier to one of my discriptions and then attached a hair system, also to my scene I added a collision object that was alembic cached that was set as a passive collider. (Note: I added a collision/force/applyNetForce modifier aswell but later found I didnt need it so removed it)

As mentioned in my first post, everything was fine until I switched to the other descriptions.

Now this is my SOS and cry for help please 😞

Thanks again

Oh and I am using Maya 2016 Ext1 sp5 and rendering with Arnold 1.2.7.2

[Anonymous]

Hi Faghrie,

I am sorry to inform you that my work around was to not use groomable splines at all. I have frequently ran into issues with these and now prefer placing the splines and working the groom this way. I don't know if this is a bug or what.

One of my colleagues had a similar issue and avoided it by always saving the same file in four different iterations. Seems a bit archaic to me.

I have written on several forums and either it has never been heard of or no one has an answer.

Best of luck searching and I wish you well.

Justin

[Anonymous]

Hi Justin, thanks for your speedy reply.

I managed to work around it somehow, I went back a few saves to when everything was normal, since Im using the hairsystem with my grooms I ended up saving the nucleus/rigid body etc presets and then transfering them onto the older scene file to avoid redoing too much. So far everything is working ok.

So yeah, it seems like a werid bug that just comes and goes as it chooses with no particular aspect causing it to misbehave.

Thanks again and good job and that hair! 🙂

Regards

[Michael_Todd]

Hi Everyone, I'm new to this forum so apologies for the lateness of this response.

The issues you seem to have been running into are a bug, that we have since fixed, where saving a scene using groomable splines with the groomable splines  hidden can cuase issues on load. If you preview the description without unhiding the splines first, you can get the exploding splines seen above.

The trick is to NOT preview, but import the groom files from the file menu:

This will rebuild the splines and you can carry on from there. A good practice is to use display layers rather than the Visibility button on the groom tab. Add the groom nodes:

then you can hide or show them from the channelbox/Layer Editor.

Again, this HAS been addressed but it's not yet out there. As a safegaurd, try not to save with the splines hidden via the visibility tag, but also you can export the groom files to a backup loaction via the Export Groom files dialogue. This location does not have to be in the default location for the description.

Cheers

[Anonymous]

Hi Michael,

Thank you so much! This is wonderful news and I thank you for the reply. I will take your advice and continue on with groomable splines. Have a good one!

J

[Michael_Todd]

you can also redirect where XGen saves and looks for files via the Edit FIle Path setting:

You can have multiple file paths, relative or Absolute or both, and XGen will look through them in order till it finds the files it needs. It will save to the forst location in the ; seperated list.

[Anonymous]

Thank you Michael, your knowledge is much appreciated. If you don't mind me asking, I do have one other question for XGen: for some reason our render farm has difficulty with XGen. It does not identify the file path while searching. I have read through the Autodesk help, but have not been able to identify the problem. Do you know of a step by step that shows Xgen with farms? I have gotten it to work once but have not been able to recreate my steps. I'm misunderstanding some concepts with when to use patch exports, exporting patches for archives, and if these need to be set to local, user, or global.

Any help on this and I would again greatly appreciate it!

Justin

[Anonymous]

Hi Todd, can you help me out with this bug? The character has Xgen eyebrows and this is what happens when you render it (Vray)

[Michael_Todd]

whats the scale of your model? It seems to be very small.

[Anonymous]

the Maya scene is set in centimeters and he's 174cm

[Michael_Todd]

What does the preview look like?

[Anonymous]

Hello!,I'm trying to cycle a ptex sequence through an expression but i'm stuck. The code i'm trying to use is

map( 'C:/map/to/file/test.%d.ptx', cycle($frame, 40, 1) )

but getting a error about xgen not finding the file path, but strange enough, if i specify the exact name o the ptex file ('test.0001.ptx') it finds it without any problems but doesn't cycle through out the sequence.

According to this page it's possible. Is this a bug or may be the 'map' function implementation is incomplete or basic? 

How could i get this to work? any ideas very welcomed!

Maya version 2016 sp6 ext1

Thanks in advance!

[Michael_Todd]

I think the 40 and the 1 in the expression are back to front. 1 is the low range and 40 the high.

int cycle ( int index, int loRange, int hiRange )

Cycles through values between loRange and hiRange based on supplied index.  This is an offset "mod" function.  The result is computed as (loRange + value % (hiRange-loRange+1)).

Cheers

[Anonymous]

Hi Michael, and thanks for the answer. May be i didn't explain myself very well, english is not my native language, sorry for that. The 40 and the 1 are fine, i was trying to play it in reverse, hence the order. The thing is that it looks like seExpr doesn't accept the format %d or %04D or anything like that to cycle a range of ptex's inside the

map('what/ever/folder/myPtexRange%d.ptx')

function, it always throws an error saying it can't find the map, or at least it is not implemented in xgen, could it be that?.
Thanks in advance!

[Michael_Todd]

That could be it, you might have to have the frame number in the ptex file name