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View Full Version : BVH migration---collapsed bones and nulls


KAMAKAZZI
08-15-2008, 06:28 AM
Hi all,

I am trying to export BVH files into Messiah but my skeleton rig from the BVH file is all collapse and not in the T pose. --Yes I have seen Marc's BVH tutorials but this problem was not mentioned---great work by the way Marc!

I have knowledge about applying the BVH in Messiah when the prop is sufficient but what do I do if I have this problem?

I think the BVH skeletal rig is inverted and might need nulls to help orientate the BVH imported rig onto the geometry in Messiah. I just dont know how or where to start. I am sure Joe Cosman knows a method or two...Wegg did mention about putting nulls on the IK solved portions but it seems a bit more laborous than that.

If anyone had this experience before---please respond. This will make my life easier with the animation process.

---I wish pmg had means to export FBX files--that would help out tremendously.

Thanks to any who respond,

Cypher

Ulven
08-15-2008, 07:52 AM
Could you post an example file to look at so we can help analyze what's wrong.

KAMAKAZZI
08-15-2008, 09:16 AM
Here is the Messiah scene:

BVH_problemMPJ (http://www.mediafire.com/?hxkp0ojau9f)

http://img209.imageshack.us/img209/4245/snap3sd0.png

Here is me exporting a BVH file from this application:

http://img401.imageshack.us/img401/764/snap4exportwu4.png

Saving the BVH file

http://img186.imageshack.us/img186/9909/snap5bvhformatdi2.png

More BVH options---the scale was set to 200 to match the up to scale model in Messiah.

http://img186.imageshack.us/img186/7638/snap6bvhoptionswk8.png

Various attempts shown selecting various options to see what would work. This round, I told Messiah that I want the BVH to be constructed with bones---here are the results.

http://img209.imageshack.us/img209/9804/snapaox8.png

Result in Setup Tab

http://img365.imageshack.us/img365/9104/snapasetuptabpk2.png

Result in Animation Tab

http://img365.imageshack.us/img365/9907/snapaanimationtabrr6.png

Now I told Messiah to construct the BVH format into bones and nulls...

http://img365.imageshack.us/img365/8562/snapbkz1.png

Result in Setup tab

http://img365.imageshack.us/img365/4995/snapbsetuptabds2.png

Result in Animation Tab

http://img399.imageshack.us/img399/5061/snapbanimationtabhz3.png

When I play the animation through the timeline of course its going to be all over the place.
Id like to add in the BVH motion on top of my Messiah rigs eventually...

The application used to create the BVH file works well with FBX. If Messiah were to allow FBX formats to be exported--I can resize the rig in Endorphin to the FBX rig from Messiah (since model and messiah rig are up to scale for game engine) and export Endorphin's animations as an FBX file ontop of Messiah rigs in a Messiah scene. Whew--that sounds confusing. So there is a reference rig needed for the simulation rig...align the bones and resize, then export.

I dont need to take that route as long as the BVH files exported can be in the T-pose so Messiah can read it properly. Only I am having these problems.

I understand the FBX data is more joint based as compared to BVH data is more for Bones.


"LightWave/Messiah uses a bone-based skeletal definition. Many animation systems and file formats—including endorphin and FBX—use joint-based definitions.

In a joint-based hierarchy, the skeleton is defined as a set of joints. Bones only exist as connections between joints, and are drawn implicitly. This means that in order for a bone to exist there needs to be a start joint, as well as an end joint for that bone. However, for bone-based skeletons—such as LightWave characters—there are no end joints.

For example, the feet of a hierarchy created in LightWave might end with toe bones, but there will be no final toe joints to terminate these bones. The FBX format requires that there be end joints—otherwise toe bones will not be created.

For this reason, at the end of each extremity of your LightWave hierarchy you will need to create an additional child bone. This can be done by selecting the extremity bone and clicking Add > Child Bone from the Setup tab. These terminating bones to not need to be active."


Any inputs would be great!

Cypher

Ulven
08-15-2008, 09:42 AM
All that info makes it sound as if, because endorphin uses joints, it does not correctly export BVH files as bones. I belive joints are position based from what I've heard elsewhere, and BVH typically records mostly rotation even for legs.

The first thing to eliminate is to figure out which program is having problems. Is it A) endorphin exporting wrong, or B) Messiah importing it wrong.

To check this you could try loading the bvh file in another application like lightwave etc. If the other program loads your file correctly you can determine that your file is ok and something is wrong in messiah, otherwise you can determine that there's something wrong with the exporter in endorphin.

Try setting scale to 1 and import it in messiah, even if it's small you should be able to determine if it is the culprit because it will look like just a small version of what you're getting now if it's not.

Is it rotating correctly, but in the wrong place? if so, could you just reposition the bones to where they should be and have them work fine?

Can you mass edit the curves into place?

Try unchecking 'cleanup animation f-curves', it could be deleting some information messiah needs.

Check if the rest values are correct in the BVH file, open it up in NotePad++ and read through it and compare it with a BVH file you know works.

Then you can contact customer support for endrophin or messiah, depending on what you learned.

Suricate
08-15-2008, 10:27 AM
Cypher, could you post the BVH file as well? I've been working on my own BVH importer for messiah and I can give it a try with your file.

KAMAKAZZI
08-15-2008, 05:07 PM
Chris,

Nice to hear from you again man. Of course I can provide some BVH files.

1-FallBVH (http://www.mediafire.com/?cgmdydtacym) - Orientation Y Axis

2-Fall BVH (http://www.mediafire.com/?aciajoxc2ma) - Orientation Z-Axis

Here is even the Endorphin scene incase you manage to get the demo...

FallScene (http://www.mediafire.com/?dxr11azahw2) - Endorphin ENS file


Thanks fellas for taking the time looking into this problem I have. Ulven, your inputs make sense and I am attempting to implement your suggestions.

Chris...your working on a BVH importer for Messiah---how cool is that! Cant wait to see it...hmmm beta tester right here...hehehe.

Cypher

Suricate
08-17-2008, 02:06 PM
Cypher,

it seems to me that it's just the native messiah BVH importer that is borked.

I opened the file with my own BVH importer and it looks OK, have a look at the attached scene file. The setup and frame 0 look rather strange, but the animation frames play fine.

There are some little things to fix with my importer, but I think I can release it the coming week.

KAMAKAZZI
08-17-2008, 05:20 PM
Whoa! See it wouldnt even play right in the animation after frame 0, its all twisted and such. What did you do in your importer? Did you re-export from your importer and re-saved the fxs format and it worked?

Strange!

Let me know what you did step by step because its not working at all from my end.

Which version did you use the Y-axis orientation, the X-axis orientation?

I saw that you added bones to the end limbs...both the arms/hands and toes...which makes sense because the toes and hands are now defined as bones.

When you opened the BVH in your importer, was it already in a T- pose fashion or did you have to fix it?

Let me know soon--your killing me here--I already spent 2 days not sleeping trying to figure out this problem.

Anyhow I am looking forward to your BVH importer...please have it out soon--Id buy it in a heart beat seeing that it will help my department tasks.

Again, thank you so much for looking into this and providing an additional tool for importing BVH files.

Looking forward to your BVH importer.

Cypher

MarkInTx
08-18-2008, 10:36 PM
The problem with the BVH standard is that things are not at all standard...

One thing I found helpful was a program you can download for free called BVH-Hacker

You can get it here:

http://davedub.co.uk/

That gives you a lot of translation options. Sometimes BVH files that "don't work" can be fixed by running it through BVH Hacker first...

Might be worth a try...


Whoa! See it wouldnt even play right in the animation after frame 0, its all twisted and such. What did you do in your importer? Did you re-export from your importer and re-saved the fxs format and it worked?

Strange!

Let me know what you did step by step because its not working at all from my end.

Which version did you use the Y-axis orientation, the X-axis orientation?

I saw that you added bones to the end limbs...both the arms/hands and toes...which makes sense because the toes and hands are now defined as bones.

When you opened the BVH in your importer, was it already in a T- pose fashion or did you have to fix it?

Let me know soon--your killing me here--I already spent 2 days not sleeping trying to figure out this problem.

Anyhow I am looking forward to your BVH importer...please have it out soon--Id buy it in a heart beat seeing that it will help my department tasks.

Again, thank you so much for looking into this and providing an additional tool for importing BVH files.

Looking forward to your BVH importer.

Cypher

KAMAKAZZI
08-19-2008, 07:50 PM
Thanks Marc for the avenue of BVHacker. I already tried that 3rd party application and I get an error that haults the program.

http://img187.imageshack.us/img187/3584/bvhackerproblemwe3.png
(http://img187.imageshack.us/img187/3584/bvhackerproblemwe3.png)

It only acts up when I use any BVH files exported from Endorphin. Chris managed to fix it and I am still wondering how did he do so. I know some bones were added but did he do that in Messiah or in his BVH importer that he is working on.

Any other suggestions would be great.

C.

Suricate
08-24-2008, 12:03 PM
Cypher,

sorry for my late reply, but another project came up. Therefore I couldn't yet fix all issues with my plugin. You can find a beta version for testing together with a description in the 'Plugins' section over at SetupTab.com .

KAMAKAZZI
08-24-2008, 09:26 PM
THANKS! This really helped! I didnt need to alter much to make the BVH files work in Messiah---too cool man. I cant thank you enough on how you made my life easier.

I plan on writing up some pipeline videos after I get more in depth in production.
Definitely will refer all to get your plugin in those videos.

I owe you big time....

Cypher

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