.3DS - 3D Studio, very common format for meshes and hierarchy animated models. There's 2 main types of animation, Mesh deformation and Limb hierarchy. .3DS supports limb hierarchy animation which is used by DBClassic, each individual mesh inside the model is linked together with pivot points and the model is animated using key frames and rotating/moving the limbs. DBPro will not load .3DS models, only .X.
.X - DirectX, Also very common, and has all the same properties as .3DS except it can support mesh deformation animation too, .X tends to be a converted format, there's a .3DS to .X converter supplied with DBC. Mesh deformation animation is unlike limbed animation because it involves setting vertices to limb positions rather than entire meshes. Using a bone system, is a bit like limbed animation, if you imagine that your animating a skeleton, and the mesh is actually the skin, the mesh will deform and bend to suit the skeleton. Makes for much smoother animation - although limbed animation is still best for non-organic or mechanical models (like robots would be best animated with limbs).
.TGA - Targa, this is an image format a little bit like a .BMP, except TGA is a much simpler format, and I think it supports an alpha channel, not sure. It's a fairly standard file format for any image really, it isn't compressed at all, so you'll hardly ever see it in a downloadable game.
To learn model implimentation, you should really just experiment mate - there's no tutorial that will do as good a job as a half hour mess about with DB. Figure out howto load an object, then howto start it's animation, then loop it's animation, then look into things like moving it and controlling the camera. Start small, only add code that you know what you want it to do - don't add too much at a time, and stick at it - you'll be on top of things in no time.
Van-B
My cats breath smells of cat food.
