# OpenGL Animated, modular 3D model implementation?

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Stuff like that tends to be game specific. Although, it's not that difficult to pull off.

1) Animate a standard mesh and skeleton. The standard mesh is just so you can see what you are working with in the 3d modeler.

2) Export it out with a script, ditch the mesh.

3) At runtime in your game, just draw the various 3d models at the positions of the bones.

A figure ends up just being a list of models that are attached to the standard skeleton.

There is also something called Cal3D, but I've never used it.

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I've been thinking about it, and listening to what most have said. Perhaps I should write my own XML file format so that the project I'm working on doesn't grind to a halt. I'll have to "hand craft" models until my next question gets answered, but I wonder if this is the best thing to do.

And this, of course, brings up my next question. How can I possibly write my own format if I don't understand the available formats well enough to write a converter? It seems to be the common suggestion to "write a game specific format," but this seems even more complicated than just reading the file itself.

Anyway, I've looked about and came up with something like this:
<?xml version="1.0" encoding="UTF-8"?><skeleton>	<figure>		<bone name="root" parent="NULL">0.0,0.0,0.0</bone>		<bone name="spine" parent="root">0.0,10.0,0.0</bone>		<bone name="cocyx" parent="root">0.0,-1.0,0.0</bone>		<bone name="shoulder_left" parent="spine">-3.0,0.0,0.0</bone>		<bone name="shoulder_right" parent="spine">3.0,0.0,0.0</bone>	</figure>	<animation name="idle">		<frame duration="1000.0">			<move target="spine">0.0,20.0,2.0</move>			<move target="cocyx">0.2,39.0,1.0</move>		</frame>	</animation></skeleton>

Then, something similar for each vertex.
<?xml version="1.0" encoding="UTF-8"?><mesh>	<points>		<vertex>			<normal>0.0,1.0,0.0</normal>			<texcoord>0.0,0.0</texcoord>			<location>0.0,3.0,0.0</location>			<weight bone="spine">0.9</weight>			<weight bone="shoulder_left">0.05</weight>			<weight bone="shoulder_right">0.05</weight>		</vertex>		<vertex>					</vertex>	</points>	<faces>		0,1,2		1,2,3		3,4,5		6,7,8		9,10,11	</faces></mesh>
The idea being that an entire mesh can be created, weighted to a bone system, then diced up into fragments and exported.

I haven't gotten much clearer advice than this, so I'd really appreciate some pointers.

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