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merovingio
06-30-2014, 06:45 AM
Hi there,

do you have a workflow to mix or blend different bvh files?

RebelHill
06-30-2014, 07:01 AM
Motion mixer... IKB, and thats about your lot in LW.

Both are VERY clunky though compared to other solutions out there, you should check out... http://www.ikinema.com/?mod=products&show=5 lightyears ahead of working just in LW.

merovingio
06-30-2014, 07:47 AM
Ikinema? I'll take a look at this.

What about IKB, can you blend animation with it? How?

Ryan Roye
06-30-2014, 07:49 AM
Both are VERY clunky though compared to other solutions out there...

Agreed. The issue isn't being able to blend the motions in the first place....

Motion Mixer: You can do it visually, but not quickly.

IKBooster: You can do it quickly, but not visually (only iteratively).

Go figure!

Ryan Roye
06-30-2014, 07:52 AM
What about IKB, can you blend animation with it? How?

IKBooster's motion format and copying allows you to take the information from a single keyframe and interpolate that into the frames of the clip you load using the PRE and POST mix fields. It works well, but as I said it is not an interactive process, you basically set the # of keyframes you wish to blend and if you don't like the result, you have to undo and then load the clip again with different settings. You can blend characters into poses as well which is really handy.

If you want to read up on IKBooster, i've made a proper manual for it: http://delura.tanadrine.com/IKBooster/IKB_UserManual.html

See also relative motion loading: https://www.youtube.com/watch?v=AdG8gvcW2y4

merovingio
06-30-2014, 07:57 AM
So basically i load a BVH file, apply IKBooster and then load another one and copy information from the sewcond one to the first?

I also own a license of Nevron Motion, can it be useful?

Ryan Roye
06-30-2014, 08:09 AM
So basically i load a BVH file, apply IKBooster and then load another one and copy information from the sewcond one to the first?

Yep! It is important that you apply IKBooster to the same item between loading/saving, so if there's overlapping master or container nulls in your mocap sample, pick the object that contains the bone hierarchy. Also:

Pre-mix: This is used most often; it determines how many frames that need to be interpolated into the clip being loaded or copied

Post-mix: This is more useful when paired with poses. For example, you can set it up so that the character blends from a motion capture clip into a pose... this basically applies the "blending" at the end of the clip.

The caveat here is positioning: every motion capture clip you use will have differing position values, so you'll have to use either the relative motion loading workflow or manually adjust things in order to get clips playing in sequence.

With Nevronmotion, its usefulness will depend on a lot of factors. I personally don't care for the workflow of using a pre-defined rig in order to work with motion capture and it makes hand-animating things (beyond minor tweaking) in-between motion capture hard. You can adapt a custom character rig for usage with Nevron, but that isn't something you'll find anywhere in its UI.

RebelHill
06-30-2014, 09:07 AM
Nope... nevron's no good here.

Honestly, you'll be best off just giving LW a miss altogether for this whole thing and go straight to IKinema, it'll make the work far faster, easier, and better.

merovingio
06-30-2014, 09:18 AM
Thank you Chazriker, what about Motion Mixer? Can it loads different bvh as well?

@Rebelhill, it is 10 dollars/m, i'll give it a try. Is it difficult to use?

RebelHill
06-30-2014, 09:20 AM
Hell no... easy as pie! As for pricing... ahhh... it *was* free (tbh other than checking it out and having a play when it was first launched, Ive had little reason to go back since, having motionbuilder n all).

Ryan Roye
06-30-2014, 09:28 AM
Thank you Chazriker, what about Motion Mixer? Can it loads different bvh as well?

With motion mixer, it is for handling animation that currently exists in the timeline, so you'd have to load your BVH, retarget your character with nevron (if you go that route), bake it, then make it a motion mixer clip, then eventually blend it using offset functions. It isn't a workflow I prefer for motion capture or animation handling... too many clicks and steps to get it working for my liking.

merovingio
06-30-2014, 10:02 AM
Ok, i have saved different animation, and i can load it and save. But when i load it it overwrite the current motion.

I am still confused about the premix and postmix stuff... are those commands, and if so, where are them? Thx.

- - - Updated - - -

I found it :)

merovingio
06-30-2014, 10:07 AM
Mh, but still overwrite motion instead of sequence it... i put the cursor at the last frame, then right click and go to load motion. I set the start to the last frame but it overwrite.

What am i doing wrong?

Ryan Roye
06-30-2014, 11:14 AM
Mh, but still overwrite motion instead of sequence it... i put the cursor at the last frame, then right click and go to load motion. I set the start to the last frame but it overwrite.

What am i doing wrong?

Without relative motion loading, you still have to position and orient the second clip manually via the graph editor so that it starts in roughly the same location as the previous after loading. It will blend the bone rotations, but IKBooster can only blend the speed of an object, not position.

The relative motion workflow is difficult to explain in text, but in a nutshell it lets you convert the positioning data from world to local space via the bind function, allowing the clip to be used easily on any similar template rig. You literally just load it and watch the character go right from where they are standing; a capability normally reserved for expensive animation programs. With Nevron, you can take this even further and allow your saved motions to be used on any rig given proper knowledge of Lightwave's animation toolset.

Motion mixer can do relative positioning, read up it and the "offset editor" in the Lightwave manual (page 275), and know that in motion capture clips, the "HIPS" bone is what usually drives XYZ motion in motion capture rigs, and that you'd set that to "REL" in motion mixer's offset editor (using the "custom" dropdown option) to make it play where the last clip left off. Again, the tweaks you do here will depend on the mocap you're working with.

merovingio
06-30-2014, 11:14 AM
I start to think is a bug. It ignores my start frame choise. It just overwrite, no matter the start frame i give it.

My workflow is i load a bvh and apply IKB > I save the entire motion as txt file. I clear the scene and load another bvh and do the same. > Now i load the previous motion and give it a start frame, but it overwrite.

Ryan Roye
06-30-2014, 11:21 AM
I start to think is a bug. It ignores my start frame choise. It just overwrite, no matter the start frame i give it.

My workflow is i load a bvh and apply IKB > I save the entire motion as txt file. I clear the scene and load another bvh and do the same. > Now i load the previous motion and give it a start frame, but it overwrite.

Did you save the motion starting at frame 0? IKBooster's motion format assumes you always save at frame 0. Your start frame should ALWAYS be 0.

Here's why:

If you save an IKBooster motion between frames 40-60, if you load the IKB motion at frame 0 it is going to offset your motion by 40 frames. In order to properly save an IKBooster motion, you must use the graph editor or equivalent tool, select all the keys in the motion capture clip and use numeric move to make the clip start where you want it to, with the very first frame of the motion capture clip positioned at keyframe 0.

merovingio
06-30-2014, 11:47 AM
I found a workflow that looks promising it involves IKB and MM togheter:

1 - Save different BVH as TXT from IKBooster
2 - Load one of the motion to IKB
3 - Deactivate IKB and open MM, create actor and save the motion
4 - Activate IKB, Load another TXT and save a different motion again in MM
5 - Repeat

Now you have all the motion you need in MM ready to blend, timewarp, etc.

What do you think?

Ryan Roye
06-30-2014, 12:16 PM
Sounds good to me. The only difficulty you will run into concerns animation clips that start with the rig orientated in different directions between start times. So, if animation #1 is oriented 90 degrees, and animation #2 is oriented -25 degrees, you will find it difficult to get things moving properly. If the clips you're dealing with are mostly facing the same direction at their start frames, you should be set for now.

tyrot
07-01-2014, 12:28 AM
year 2014 - and we still deal with workarounds between - MM and IKB- .. someone... "a good coder" should update them both and merge them together...