Houdini won't alembic particles to Maya

[Enemmy 0]

So I setup an easy Particle system on Houdini, and when I try to Alembic it doesn't works, just FBX does.

Can anyone please make an easy Houdini file with all setup for Alembic ROP a particle system?, so I can see whats the diference between it and mine.

(I cant share mine because the source is a Bgeo sequence of 360 files)

Im on H12 and trying to export alembic to Maya 2013 x64

Edited September 6, 2013 by Enemmy

[pclaes 293]

2 things to try:

1) if you are exporting from rops, make sure your display flag on your obj is on, and your render flag set to the correct sop

2) I had problems with exporting 'empty' alembics before, I noticed that if I choose the first frame when there is some geometry as the start frame for the alembic, it bakes out all the geo. -- As you can imagine it is quite annoying trying to find which is the first frame when there is actual geo.

[Solitude 150]

A simple solution I've used in a similar case (not alembic, but a proprietary thing) was to put a tiny box at the origin (or where you would never see it), and use a switch -- if the npoints(inputgeo) was 0, use the box, else use the particles/geo.

[Enemmy 0]

pclaes

Nothing worked

Solitude

Sorry I didn't understand completly, I speak spanish and it gets dificult

any of you guys could setup a .hip file with a Alembic ROP setup to export particles?, It would be the easiest way to me to see my error.

I really appreciate help thanks

[Tom 7]

If you havent generated any points on first frame of export, then alembic file will be empty. Just set export frame range on first frame when particles appear.

Edited September 7, 2013 by Tom

[Enemmy 0]

2 things to try:

1) if you are exporting from rops, make sure your display flag on your obj is on, and your render flag set to the correct sop

2) I had problems with exporting 'empty' alembics before, I noticed that if I choose the first frame when there is some geometry as the start frame for the alembic, it bakes out all the geo. -- As you can imagine it is quite annoying trying to find which is the first frame when there is actual geo.

If you havent generated any points on first frame of export, then alembic file will be empty. Just set export frame range on first frame when particles appear.

Oh I just understood what it meant, thank you guys, that's an Alembic bug or what?

theres another problem, so I just tested it once and it worked like a charm

but then I tested it again in a new scene and I get an error with the same .abc file that just worked

I attached the alembic file that is giving me problems.

I exported the particles from Houdini 12.5.427 and imported to Maya 2013 x64, and I did exported from the frame that I had particles

(I will link the file from my dropbox because this Forum doesnt let me upload .abc)

Alembic file:

https://www.dropbox.com/s/nxjb0gi6tkk0goj/Alembictest.abc

Edited September 7, 2013 by Enemmy

[wateryfield 17]

https://vimeo.com/70025371

A advanced new tool.

[Enemmy 0]

Lol I downloaded it and can't get it to work, I do everything wrong I guess

I did:

1.- Downloaded

2.- Put the folder "pw_mGeo" on \Python\Lib\site-packages\

3.- Open Maya 2013 x64

4.- On script editor write:

import pw_mGeo

pw_mGeo.show()

5.- Executed it and doesnt works (I used both, MEL and Python

[mangi 59]

Have you tried exporting the Alembic from Maya, & then import that same alembic back into maya to see if it is okay.

As you can see, the particles are also not showing up.

At least in the version I have at the moment. so It really has nothing to do with Houdini.

Cheers

Mangi

[MENOZ 36]

I had the same problem, importing alembic particles to maya, and it doesn't work. I asked in another forum and they said that in bigger studios they have their own version of alembic importer for maya. This because is customised for their needs, and also because the alembic importer for maya, when it comes to paritcles, fails.

It has something to do with how the particle system in maya works, that is not compatible with alembic straight away (it's a bit blurry here..), so basically it seems that alembic importer for maya is bad implemented, particle wise. I would not be surprised anyway, they have cool tech but always half developed, bad implemented.

you can export particles from maya and read in houdini, but you cant import maya particles back into maya using alembic.

This was with maya 2013. I don't know if anything changed, but I suspect no, since there are bugs that are still unresolved since maya 8.

EDIT: I see also maya 2014 still have the same problem. I just say LOL

Edited September 8, 2013 by MENOZ

[Enemmy 0]

Have you tried exporting the Alembic from Maya, & then import that same alembic back into maya to see if it is okay.

As you can see, the particles are also not showing up.

At least in the version I have at the moment. so It really has nothing to do with Houdini.

Cheers

Mangi

I had the same problem, importing alembic particles to maya, and it doesn't work. I asked in another forum and they said that in bigger studios they have their own version of alembic importer for maya. This because is customised for their needs, and also because the alembic importer for maya, when it comes to paritcles, fails.

It has something to do with how the particle system in maya works, that is not compatible with alembic straight away (it's a bit blurry here..), so basically it seems that alembic importer for maya is bad implemented, particle wise. I would not be surprised anyway, they have cool tech but always half developed, bad implemented.

you can export particles from maya and read in houdini, but you cant import maya particles back into maya using alembic.

This was with maya 2013. I don't know if anything changed, but I suspect no, since there are bugs that are still unresolved since maya 8.

EDIT: I see also maya 2014 still have the same problem. I just say LOL

Hahahaah thanks, I thought I was doing something wrong, Also, Mangi can you help me with my problem with "pw_mGeo" ? (my post on top of urs)

Or do I have to make a new thread?

[mangi 59]

Thanks Andrea for your clarification.

There is a plugging we did some test some time ago and we did import some particles from Houdini via alembic into maya , not to sure if we had some kind of issue with the velocity attribute , for the motion blur.

This was some time ago with the beta version , but maybe we can give it a crack or something . Just for the sake of this test.

http://exocortex.com/

http://exocortex.com/products/crate

there is a trial ?

cheers

mangi

Edited September 8, 2013 by mangi

[LaidlawFX 262]

Hey has anybody bug submitted this to SideFX yet? I couldn't find a fix in the journals and it is quite annoying to set geometry to the first frame. The rop alembic is so sadly not robust compared to the rop geometry.

[dennisvolkerts 7]

I also cant export any particles from houdini to maya. I heard that alembic cant export particles.

some other option should be: to use the realflow plugin for houdini to convert it to a .bin...  and open those .bin with the realflow plugin in maya.

[dpap 11]

Same problem hear ...Although I have particles from frame zero Maya won't import them. Meshed particles work fine. I even tested Exocortex Crate to import the particles in Max and still no luck. So I guess it's not only maya's fault..

[LaidlawFX 262]

Same problem hear ...Although I have particles from frame zero Maya won't import them. Meshed particles work fine. I even tested Exocortex Crate to import the particles in Max and still no luck. So I guess it's not only maya's fault..

What version of Maya are you using? I think 2012 the version prior to the pipeline Cache we used exocortex only to import particles since the native did not work. 2014 alembic import kind of works assuming in houdini you have particles on the first frame, and the display/render flag is set on the node above the sop version of the alembic rop. Unfortunately the sop alemebic rop acts like a out rop and not like the geometry rop in sops. Also make sure their are no error flags going up the pipe in houdini, an error flags will stop export in houdini.

[dpap 11]

I am using Maya 2014 extension .

 

Modo wont import them either..

 

 

display/render flag is set on the node above the sop version of the alembic rop

 

Yeap . checked it.

 

In Houdini I get no errors and I read back the the particles that I export.

But in Maya I get his

// Error: line 1: particleShape1: Object not found for -object flag. // 

I finaly used Crate to import them into Maya which is not actually a sollution because with 2 million particles when you scrub the timeline after a second the whole thing freezes.

 

 

I don't know who's to blame here (Sesi or Autodesk) but the bottom line is that something needs fixing....

[LaidlawFX 262]

I am using Maya 2014 extension .

 

Modo wont import them either..

 

Yeap . checked it.

 

In Houdini I get no errors and I read back the the particles that I export.

But in Maya I get his

// Error: line 1: particleShape1: Object not found for -object flag. // 

I finaly used Crate to import them into Maya which is not actually a sollution because with 2 million particles when you scrub the timeline after a second the whole thing freezes.

 

 

I don't know who's to blame here (Sesi or Autodesk) but the bottom line is that something needs fixing....

http://www.youtube.com/watch?v=vVlX9Ve5Rv4 There is def some wonkiness on both sides, haven't been able to define the bug as much since I've been working on commercials timeline, and if it's not quick to reproduce the error I've had to ignore it.

 

Have to say I haven't tried with 2 million particles. It may just be the size being read into Maya with the crapping out part, IO issues on maya end coming from ram or vram. Have you tested in your pipe a small threshold say a thousand, and worked up to a hundred thousand, split and merge the particle stream.

[dpap 11]

Hahaha!!! That was really funny! But I am afraid only the users are going to be seriously hurt...

 

 

 It may just be the size being read into Maya with the crapping out part, IO issues on maya end 

say that again....

 

 

 

split and merge the particle stream.

i'll give that a try

 

 

Thanks for your help Ben! And for the video!

[LaidlawFX 262]

If the split and merge of the particles works up to a certain size. Then it's probably a programming reading issues of the alembic file from disc. Not sure if you caught this simpson's vid before but pretty much the reader of the alembic file whether from the hard drive or the video ram can only fit so many things onto the screen before it can't get enough through the door and just kind of craps out. Instead of being invincible it does what maya always does and just crashes...

 

Could possibly be a coding read issue combo of the type of hardware you have, where as SideFX may have programmed out the issue Autodesk and Modo hasn't. As much as everyone praises alembic and it does get better, unless you have large studio support an issues such as this is a no go to solve from the user end, and you have to go around it. But hey Sony is firing folks left and right so you may be able to hire a developer for your own issues, lol.

 

I hate this bug set.