mat Posted October 20, 2009 Share Posted October 20, 2009 (edited) ok, lets say i took an object from maya, shattered it and simulated RBDs in Houdini and then want to go back to Maya as individual keyframed objects, how would i go about that? FBX doesnt translate the DOPS cache to channels, so there is no animation exporting chan data and reattaching in maya seems to only work for single objects, not hundreds of primitives does anyone have a good workflow? Edited October 20, 2009 by mat Quote Link to comment Share on other sites More sharing options...
edward Posted October 20, 2009 Share Posted October 20, 2009 The Dynamics CHOP can be used to obtain all the transforms of the different DOP objects. So it's fine from the Houdini side of things. In Maya though, how are you applying the .clip data? I'm also assuming that you had broken it up into separate objects in Maya? Quote Link to comment Share on other sites More sharing options...
mat Posted October 20, 2009 Author Share Posted October 20, 2009 The Dynamics CHOP can be used to obtain all the transforms of the different DOP objects. So it's fine from the Houdini side of things. In Maya though, how are you applying the .clip data? I'm also assuming that you had broken it up into separate objects in Maya? i export the geo from houdini as an obj, bring it into maya, so i have all the broken pieces (they were broken in houdini), then i select the pieces and run a python script which is supposed to apply the chan data, but it is not applying it correctly, the pieces jump everywhere, it may require the pieces to be named a certain way or selected in a specific order. Quote Link to comment Share on other sites More sharing options...
edward Posted October 20, 2009 Share Posted October 20, 2009 I didn't think you could export geometry as separate objects from Houdini via the .obj file format? So it sounds like that is the problem you have. ie. You need some way to export the geometry from Houdini and import them into Maya as separate objects (or shape nodes or whatever Maya calls them). Ok, that I have no clue about. Sorry, can't help you there. Naturally, name matching is used for everything so if you don't have set up correctly, it probably won't work. Quote Link to comment Share on other sites More sharing options...
Ratman Posted October 20, 2009 Share Posted October 20, 2009 Back at my last job I had to do the exact same thing, but FBX didn't work right since all I got was all the geometry moving using a vertex cache, which made things swim(bug maybe in FBX). So In the end I setup a Houdini scene that would export out each piece of geometry as it's own obj and a chan file to acompany it, then inside maya It would read it back in an assign the animation to from the chan file. So it would spit out a bunch of keyframes on the obj pieces. It's a little tricky, since you have to create a custom pivot attribute to get it right, but It didn't take more then 4 days to get the whole thing working. I've got it somewhere in my laptop at home, so I'll try to clean it up a bit if I have some time tonight and post it up. Dahr rreed: With the Dynamics chop you gotta export P (pivot) T (translate and R (rotate). In Maya you'll have to create an actual custom Pivot attribute where you apply your P to it. Edit 2: I think the way you had exported everything from Houdini was all mashed up, which won't work. You need to have the obj chunks and chan for it exported individually. So like: obj piece -> chan file chunk_1.obj -> chunk_1.chan chunk_2.obj -> chunk_2.chan chunk_3.obj -> chunk_3.chan And so on, I exported things this way using Delete sop and chop, and just using the $F var for the piece number, then just use a rop output with the piece count as the range. Edit 3: Also the Maya importer would rename each piece based on the name of the file, so things would be allocated correctly and everything would have the correct name. Quote Link to comment Share on other sites More sharing options...
mangi Posted October 20, 2009 Share Posted October 20, 2009 Hi there, Well I am not on maya , I use xsi at the job here in madrid spain www.pocoyo.com anyway I do use houdini for A will back and I cam across this same project. I am not to sure how FBX treats these things and when It did come up (the FBX i did not get any real results, that was at least a year ago.) Anyway I did get a script made in xsi to read in a chan file , it work using the exact peace that came from you fractured object made in houdini. I reall was con able to get the thing going one 100 % , but it was some confetti thing so the rotation from one program to another did not work quit the same. I am not to sure how big the thing you want to transport, but there are several manuel ways you can attact this . It just cam to mind right know , if you have ever used realflow you can trick the to programs in thinking that they are SD objects and read them back and forth via real flow. Of cource you have to know some basic's with that program, But I ma sure in a short time anyone can learn to import and export , theres a 30 trial . Anyway I would personally go for a point cache , this is quite tidious, but hay it is really lite when you get the scenes info from one end to the other. Know I did the project via xsi and houdini , but the point cache is thew same for each, houdini is really fast exporting that. Know if it is not really a big thing and you got some power on your pc Hell I got a few megas of OBJ sequences, It's uite a pain and slow but hey 100 % accurate http://www.creativecrash.com/maya/downloads/scripts-plugins/modeling/c/-obj-sequence-loader make your dop , get a Geo with a dop import SOP and bake the out wit a ROP via parts, example,parts.$F4.obj and then just use that script. what this dose it bring in all the obj's into the 3d app maya in your case and with a show hide , (the visibility node that all programs have). this is really heavey and really a slow, but hey it work's , you are goan need a shiy load of ram, and alot of disk. its kind of like when you make some sim in houdini and save out the dot sim files. bgeo sequence it's all the same. well I could go on further the MDD is really the best and fastes way , all the documentation is on the houdini help , here you have a snap shot MDD is really the same in all the 3d apps. cheers and good luck. mangic Its kind of like a bomb dive or something. Quote Link to comment Share on other sites More sharing options...
mat Posted October 20, 2009 Author Share Posted October 20, 2009 I didn't think you could export geometry as separate objects from Houdini via the .obj file format? So it sounds like that is the problem you have. ie. You need some way to export the geometry from Houdini and import them into Maya as separate objects (or shape nodes or whatever Maya calls them). Ok, that I have no clue about. Sorry, can't help you there. Naturally, name matching is used for everything so if you don't have set up correctly, it probably won't work. yeah, i just made an object_merge and checked "create primitive groups" and when i exported that i get an obj with all my objects as separate pieces of geometry back in maya, now if i could only assign the .chan onto my pieces id be set. Quote Link to comment Share on other sites More sharing options...
mat Posted October 20, 2009 Author Share Posted October 20, 2009 (edited) thank you ill try looking into MDD. I have used realflow, does the SD format read in dops as keyframed animation? Edited October 20, 2009 by mat Quote Link to comment Share on other sites More sharing options...
mat Posted October 20, 2009 Author Share Posted October 20, 2009 (edited) thank you ratman... sounds a little complicated to set up but it could work. Any chance you could upload a .hip file with that setup on something simple so i could see how it works? Edited October 20, 2009 by mat Quote Link to comment Share on other sites More sharing options...
Ratman Posted October 20, 2009 Share Posted October 20, 2009 It's a bit tricky to get it setup, but once it works, it'll work! I don't remember the whole thing since I've barely touched both things lately, so I'll have to check it out when I get home and see what the secret ingredients to get it working are. Quote Link to comment Share on other sites More sharing options...
Ratman Posted October 20, 2009 Share Posted October 20, 2009 I used something like this, tested it and it should spit out the data in the same way I used it, a bit crude, but it worked for what I needed it to chan_write_v1.hip Quote Link to comment Share on other sites More sharing options...
mat Posted October 21, 2009 Author Share Posted October 21, 2009 i got a pretty simple solution, fbx actually works, but it brings it in as a single object with a point cache. This is not really what i want though, id still prefer individual objects with anim curves that could be further processed. Quote Link to comment Share on other sites More sharing options...
Ratman Posted October 21, 2009 Share Posted October 21, 2009 i got a pretty simple solution, fbx actually works, but it brings it in as a single object with a point cache. This is not really what i want though, id still prefer individual objects with anim curves that could be further processed. That was my exact problem with it, since it also gave swimming point data, so UVs would be going crazy, at least on my side. Quote Link to comment Share on other sites More sharing options...
mat Posted October 21, 2009 Author Share Posted October 21, 2009 (edited) I used something like this, tested it and it should spit out the data in the same way I used it, a bit crude, but it worked for what I needed it to ok it worked! thank you. Edited October 21, 2009 by mat Quote Link to comment Share on other sites More sharing options...
Ratman Posted October 21, 2009 Share Posted October 21, 2009 ok it worked! thank you. Sweet, was it the pivot thing? :-D Quote Link to comment Share on other sites More sharing options...
mat Posted October 22, 2009 Author Share Posted October 22, 2009 Sweet, was it the pivot thing? :-D yes, maya couldnt interpret pivot, so i had to just export translate and rotate, and then in maya center all pivots. worked like a charm. Quote Link to comment Share on other sites More sharing options...
Zanozza Posted October 27, 2009 Share Posted October 27, 2009 (edited) One more idea: 1. Create object in Maya. 2. Provide to Houdini. 3. Shatter (or something to do). 4. Import back the chunks. 5. Connect with Houdini by port connection (this way). 6. Grab the DOP information by Maya Python, frame by frame and bake the keys. Check this video. Edited October 27, 2009 by Zanozza Quote Link to comment Share on other sites More sharing options...
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