PDA

View Full Version : Parent Null to MDD object?



Imatk
10-20-2007, 04:48 PM
I've got an animation baked out from XSI with Point Oven.

I'm using LW 9.3 and have imported the objects and pointed them to the .mdd file and everything is groovy.

Problem is I can't seem to parent a null to any of the objects.

I mean I CAN parent it but it doesn't move with the .mdd object. It just remains at the origin.

I realize that's because actually the object IS at the origin if it were not for the .mdd file. But how do I get this null moving with my object?

I need to parent it and use it for some particle work to interact with my character.

Thanks for any help.

evenflcw
10-20-2007, 05:24 PM
Bake out the motion of a point by appying SoftFX or ClothFX, disabling anything that causes displacement and using EditFX Make Path option. Or use a parent2point plugin or dponts Node Motion Modifiers and Point Info node.

Imatk
10-20-2007, 05:33 PM
Thanks for the reply... I'm not sure I understand your solution though.

I'm new to the whole moving stuff from XSI to Lightwave etc.

Could you give me step by step?

Thanks man.

SplineGod
10-21-2007, 04:35 AM
Import the mdd file onto your object using clothfx and then use the editfx tool in the clothfx panel to select a point and extract its motion.

Cageman
10-21-2007, 10:24 AM
Or, if you are using LW9.x on Windows, download Item Motion Node (motion modifier) and the latest version of DP Kit (both can be found here (http://perso.orange.fr/dpont/plugins/nodes/Additionnal_Nodes_2.html)).

You then simply apply Item Motion to any object (nulls, lights, bones or cameras) and tell it what point on what mesh it should constrain to. The good thing about this method is that if you would update the MDD from XSI, the constrain will respect that. The other methods mentioned requiers you to re-scan the deformed mesh using SoftFX and than export a null if you update the animation.

I've attached a screenshot of the node-conection.

EDIT: Sorry evenflcw, didn't see you mentioned Node Item Motion... :)

Glendalough
10-21-2007, 11:34 AM
Import the mdd file onto your object using clothfx and then use the editfx tool in the clothfx panel to select a point and extract its motion.

I wouldn't do it this way exactly actually. Use clothFX as Larry says, but go to the File tab and then 'Playback Mode' switch to 'Local'. If the MDD file is parented to the null you can now move, rotate, size etc. and the MDD object will follow.

Speaking of MDDs does the MD_MetaPlug work at all, i.e. does anyone have experience of using it.

Is the 'cage object' meant to be the original object used when generating the MDD file. Anyway, have tried all combinations and can not get the more detailed, replacement mesh to deform. On the Mac it does absolutely nothing. In Windows it floats around in a weird and vague irregular arc or circle. None of the objects are sub-ds.

Anyone have any clues Please?

Sorry for Hjacking thread but thought to put this here rather than start new as closely related and maybe some of the experts here can tell me -Larry -Cageman???

Imatk
10-21-2007, 12:01 PM
Thanks very much guys :)

Cageman
10-21-2007, 12:42 PM
I wouldn't do it this way exactly actually. Use clothFX as Larry says, but go to the File tab and then 'Playback Mode' switch to 'Local'. If the MDD file is parented to the null you can now move, rotate, size etc. and the MDD object will follow.

Very true, but that's not what Imatk asked for. He want's to parent a null to a specific point on a deformed mesh. :)



Speaking of MDDs does the MD_MetaPlug work at all, i.e. does anyone have experience of using it.

Is the 'cage object' meant to be the original object used when generating the MDD file. Anyway, have tried all combinations and can not get the more detailed, replacement mesh to deform. On the Mac it does absolutely nothing. In Windows it floats around in a weird and vague irregular arc or circle. None of the objects are sub-ds.

Anyone have any clues Please?


Never used it actually. :/ It seems to be one of those old relics from the time before LW8.x when LW still didn't have the Dynamics-tab and relied heavily on MotionDesigner. I was never able to do anything dynamics-related prior to LW8.x. :) Larry has been with LightWave since the beginning so he probably knows a hell of alot more than I do about those old strange things. :)

Glendalough
10-21-2007, 12:58 PM
Very true, but that's not what Imatk asked for. He want's to parent a null to a specific point on a deformed mesh. :)

Never used it actually. :/ It seems to be one of those old relics from the time before LW8.x when LW still didn't have the Dynamics-tab and relied heavily on MotionDesigner. I was never able to do anything dynamics-related prior to LW8.x. :) Larry has been with LightWave since the beginning so he probably knows a hell of alot more than I do about those old strange things. :)

Oh Sorry (Larry), got that backwards.

Cageman: I was thinking that about the old MotionDesigner, maybe should try it that way. Have had more trouble with the new Dynamics, getting used to them, but they are better.

Is there anyway with what ships with Lightwave to make one mesh deform another, similar, but not the same point/poly count? Like to use one model as a cage on another?

Cageman
10-21-2007, 01:22 PM
You can use FX_MetaLink. Apply cloth to a lowres object and parent the highres object to the lowres clothobject and apply FX_MetaLink to the highres object. This will transfer the motion from the lowres (cage) object to the highres without the overhead of heavy calculations.

Glendalough
10-21-2007, 02:01 PM
You can use FX_MetaLink. Apply cloth to a lowres object and parent the highres object to the lowres clothobject and apply FX_MetaLink to the highres object. This will transfer the motion from the lowres (cage) object to the highres without the overhead of heavy calculations.

KOOL! Thanks alot, it works!

evolross
09-23-2010, 09:30 PM
I found some kind of bug using the Point Info Node as described above. I had a crowd simulation driven by MDDs and needed to parent a few props to various crowd members.

I used the Point Info Node and it works great but it takes an entire frame for it to start working. So when I render out my sequence, all the props sit for a frame and then start moving, while the MDDs all start on the first frame.

I couldn't figure out any work-around except to render one frame longer, and cut off the first frame in comp. I'm lucky I could do this and that all my MDDs were looping. I even tried starting the sequence at 0, -1... none of that worked.

Any ideas Denis?

Cageman
09-23-2010, 09:57 PM
Solution:

1) Constrain your object using Node Item Motion
2) Go here: http://mentalfish.com/2009/09/motion-baker/ and download it
3) Select your Node Item Motion driven items and use the motion baker to convert the constrain(s) into keyframe data (yes, you can bake multiple items in one go).
4) Disable or remove Node Item Motion modifier. I usually disable it, since there might be updates down the line.

:)

MentalFish
09-24-2010, 12:27 PM
If only my MDD ReAnimator LScript was finished, this would have been a one button click, right Mikael? :)

I want my 36 hour day cycle now, so I can get some stuff done... pfff

Cageman
09-24-2010, 12:29 PM
If only my MDD ReAnimator LScript was finished, this would have been a one button click, right Mikael? :)

I want my 36 hour day cycle now, so I can get some stuff done... pfff

Yeah... MDD ReAnimator would have solved this in a very short timeframe. :)

phillydee
09-24-2010, 01:36 PM
Why don't you just create the necessary nulls in XSI, parent/constrain them, and then export the nulls out of XSI using PointOven? You have to select the nulls, and then in PO make sure you select "Nulls" and save out the LWS as well as the MDDs that you want to export... opening the scene in LW that PO created will reveal the nulls that got exported out of XSI.

evolross
01-11-2011, 02:57 PM
I wanted to revisit this, now that I finally have time. I made a test case that mimics the previous issue I was having which was attaching a prop to an object deformed by an MDD.

My old issue appears to be fixed, as there isn't any delay with the prop moving with the object. I did update to Denis' latest DP Kit for LW 10 so maybe that fixed it.

I have another question now... the prop is moving with the point correctly :bowdown:, but what do I need to do to have it orient correctly with the object IF I wanted it to? In this example, make it orient to the normal of the green patch on the ball or in other words point in the directly of the green patch?

I attached my scene and some screen shots.

BTW: The new MD baker works good, except I think I found a bug. It won't bake out a file unless the folder listed in the path actually exists. Meaning it won't create a "VertCache" folder for you. I'm going to fog it.

evolross
01-11-2011, 03:14 PM
Figured it out by looking at another thread. You need to break out Denis' Node Item Motion on the "Motion Options" of the prop, then use a Point Info Node from the main object to drive the motion of the prop.

I also had to modify the pivot point of the prop so it would rotate at its end properly.

Intuition
01-11-2011, 04:25 PM
Jamie! You back in Los Angeles or is it just that your profile info is old?

erikals
01-11-2011, 11:14 PM
off topic... but might be of use? :]

displacement map on an MDD
http://www.youtube.com/watch?v=xF46N2ENAZc

Greenlaw
01-12-2011, 12:04 AM
You can use FX_MetaLink...
I was going to suggest this but Cageman beat me to it. :)

This is basically how I get hair and long fur guides 'parented' to .mdd files exported from Maya. The cool thing is that if you use ClothFX to read the data, you can animate the hair/fur guides.

Note: FXMetalink ONLY works with ClothFX; any other .mdd reader will just ignore FXMetaLink and FXHardLink. There is also an issue if you want to use Displacement Mapping on the mesh; I'll have to check but if I remember correctly, you need to set the order to Last for FXMetaLink to work but unfortunately this removes the effect of Displacement Mapping...or something like that. This long-standing issue messed us up on a recent job and because of that we're looking to do hair and fur guides animation in either Maya or Houdini now. :(

erikals
01-12-2011, 02:30 AM
...couldn't you just use 2 sets of FXMetalink ?