# OpenGL Skeletal Animation Problem

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I know the general idea. I've been trying to learn exactly how it works, because I'm writing an exporter for Maya, importer into OpenGL. There is access to Maya's bone information, but I wouldn't know how to use the data, or what any of it means. I'm a little confused on how to use the bone information to affect the vertice data. I've figured out you do the inverse of the matrix, but that's about all I've been able to determine from online resources. I don't understand which matrix, or where the matrix comes from. Any help on the math portion would be greatly appreciated. Pretty much anything specific to how the vertices are controlled would be great.

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its really just a large tree. the bones are nodes and the vertices are leaves attached to the nodes. this allows you to move the model as an entire unit or ensure that when you move the arm the hand and fingers dont stay behind.

the math is just a quaternion or matrix static, once youve defined the relationship between the vertices(which is the entire purpose of bones), then the rest is common sense.

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Thank you for telling me "its really just a large tree. the bones are nodes and the vertices are leaves attached to the nodes. this allows you to move the model as an entire unit or ensure that when you move the arm the hand and fingers dont stay behind." Now that I've heard this 30 times in 30 different ways, I think I just MIGHT have that down.

Care to elaborate more on "the math is just a quaternion or matrix static". How do parent bones affect the child bones matrices? Ive searched 2 days now for a good site or tutorial and haven't found anything.

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Hehe... you sound exactly like I did 10 days ago=)

Well I wrote a thread about just the same. Take a look at it in this same forum. Thread is called "Problems with Skeletal Animation". If you have more questions specific about the math, let me know. I havent got the implementation work yet but im ......soooo close=)

I too had 40 people tell me the same stuff over and over again... stuff I couldnt use for anything... I soon found out that they had never made a working implementation them selves, VERY few has. They could only speak in generel terms! Its a VERY frustrating topic - get used to it or you will just add to the statistics and become one of the many that give up!

If you are on msn you can message me if you like. msn: jplindberg@hotmail.com

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Alright, I added you. Yeah I read your post as it had nearly the same title as this one lol. It did help some. I pretty much figured out that not many people knew what was going on behind the scenes. People keep telling me to use 3DS or something with bones built in and just use a pre-made importer. Well guess what? I don't like the easy way out! Hope to catch you on msn!

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