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View Full Version : Rigid animation vs what?



pcas1986
June 6th, 2015, 11:34 PM
In the chunks thread Chris made this statement:

If you're using rigid animation, go easy on the bone count. Ideally, avoid rigid animation. It's very much a legacy technique from the pre-shader days.


What exactly is rigid animation in a Trainz context and what is the name of an alternative?

In an XML TrainzMeshImporter log I have seen this statement:


Info: Forcing Rigid Skeleton due to material types used


Which material types cause this action? I believe this includes normal mapped materials.

How do I avoid using rigid animation when I am not consciously selecting it?


I would like to see more information on this issue as it relates to Trainz content creation.

ZecMurphy
September 21st, 2015, 09:39 PM
Hi Paul
Essentially the other method is a 'skinned' animation. I'm not sure how this is achieved with blender, unfortunately. I think they also use the term 'rigged' animation.

With 3DSMax, it's achieved using the 'skin' modifier, although the 'physique' modifier can also be used for similar results. All parts of the animation need to be attached as one object, although you can also have attachment points in the mix. The same bones/dummies are used, but they control vertices rather than objects.

This animation method allows you to directly animated vertices, rather than objects. It's the 'go to' for 'organic' animations (people, animals, etc), as it allows parts to deform.

The best place to look will be at the tutorials for animating people; and you should be able to adapt this to use a 'skinned'/'rigged' animation for Trainz.

This method works exceedingly well for coal loads (deforming them quite nicely), and I've also had a lot of success using it for brake hoses, and various other animations.

Regards

pcas1986
September 22nd, 2015, 03:00 AM
Thanks Zec. Currently I'm overseas so I'll have another look at this when I get back.

WindWalkr
September 22nd, 2015, 03:12 AM
How's Italia? ;-)

chris

Pencil42
September 22nd, 2015, 09:00 AM
Blender may call this vertex animation? Torsten has a couple of examples in the example files that are available with his exporter; including an animated bulk load. I (eventually) got it working for the animated bell rope on my mogul update last month.
Like you saw from the importer logs, it doesn't work on normal-mapped materials, which sorta limits it's use on bulk loads (in my opinion). It also tends to force a second material type, since I'm usually using a normal-mapped material for my main material.
I think there may also be a fairly steep limit to the number of bones / vertex groups you can use per mesh - something like 4, perhaps? Chris would know better...

Curtis

pcas1986
September 22nd, 2015, 10:24 AM
How's Italia? ;-)

chris
Hot, sticky and full of tourists. Just like the Gold Coast. :D

pcas1986
September 22nd, 2015, 10:31 AM
Blender may call this vertex animation? Torsten has a couple of examples in the example files that are available with his exporter; including an animated bulk load. I (eventually) got it working for the animated bell rope on my mogul update last month.
Like you saw from the importer logs, it doesn't work on normal-mapped materials, which sorta limits it's use ....
Curtis

I played with that as well. When I have the time I'd like to explore our current boundaries so we might put a case together for improvements. I think Trainz might benefit from better people animations.

WindWalkr
September 22nd, 2015, 06:37 PM
Like you saw from the importer logs, it doesn't work on normal-mapped materials, which sorta limits it's use on bulk loads (in my opinion).

Not sure where this limit is coming in. It's not fundamental. Might be an artificial limitation in the TMI.



I think there may also be a fairly steep limit to the number of bones / vertex groups you can use per mesh - something like 4, perhaps? Chris would know better...

There's a limit of four bone PER VERTEX. If you go above that, things should still work but the code will just throw away the weakest influences until you're under that limit.

There is also a practical upper limit to the number of bones, but if you come close to hitting that then you're also doing a horrible job performance-wise so we don't pay a lot of attention to that one.

chris

WindWalkr
September 22nd, 2015, 06:39 PM
Hot, sticky and full of tourists. Just like the Gold Coast. :D

Except, y'know, with better food, wine, coffee, art.. :)

chris

Pencil42
September 22nd, 2015, 11:14 PM
Might be an artificial limitation in the TMI.
Feel free to remove it (at your convenience.) I wouldn't mind being able to use normal-mapped materials with the vertex animation :)

Curtis