Understanding Irrlicht Animation inner workings

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Lambda
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Understanding Irrlicht Animation inner workings

Post by Lambda »

Hello,

I'm trying to understand how the internals of the irrlicht skinned mesh animation system actually works, by reading the code of the loaders i guess i figured out what exactly each matrix represents, however i would love if someone can confirm my thoughts.

Joint LocalMatrix contains the transformation relative to its parent joint.
Joint GlobalMatrix contains the transformation in object space (relative to the mesh itself), on root joints, LocalMatrix equals Globalmatrix.

Is that correct? I ask because i am working on a custom animated mesh format and im about to write the export code for the bones and need to know how irrlicht does handle this in order to write the most optimized export format.

Thank you guys :)
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Lambda
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Re: Understanding Irrlicht Animation inner workings

Post by Lambda »

I answer myself since nobody did, after doing some more research it looks that i was right, LocalMatrix is the transform of the bone relative to its parent, globalmatrix is then built by the CSkinnedMesh iself based on the bone and their parents LocalMatrices, same apply for position/scale/rotation keys, they're relative to the bone parent. :)
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hybrid
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Re: Understanding Irrlicht Animation inner workings

Post by hybrid »

Yeah, sorry. The animation system has lost the maintainer long time ago, and is special in several regards. So there's not much knowledge of the internals available. But if you can provide some documentation for the ISkinnedMesh headers or some examples, it would certainly help for the future.
Lambda
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Re: Understanding Irrlicht Animation inner workings

Post by Lambda »

Well i dont know much of it yet but i will have to deal quite a bit with it soon since i have plans to rewrite it from scratch to add support for animation tracks, vertex and skeletal animations together, hardware skinning and other stuffs im on need for the project im working on so i will try to post whatever i discover
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Mel
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Re: Understanding Irrlicht Animation inner workings

Post by Mel »

I have found today some interesting reads in that matter:

The animation in videogames

From what i have read, it just looks like what Irrlicht does.
"There is nothing truly useless, it always serves as a bad example". Arthur A. Schmitt
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