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DrJim
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Default 05-13-2007, 11:40 AM

Quote:
Originally Posted by Shaba1 View Post
....That indicates that she had joints and some type of skeleton.
Joints yes – skeleton no. An Alice character object is just a hierarchy of sub-objects joined together with fairly arbitrary (and totally unconstrained – you want an arm to bend 360 degrees - OK) parent-child relationships. Each sub-object has its own texture. Although textures can be assigned to the object as a whole, that assignment will be overridden by a texture assignment to a sub-object (actually a nice feature if you want to change facial expression or do something similar).

Blender and most other high-end 3D animation programs make a distinction between the overall texture/skin of an object and its skeleton/armature. They then define relationships (often multiple ones) between specific surfaces of the skin and individual parts of the armature. Of the free programs, Milkshape does this particularly well, in my opinion. Blender is much more powerful, but (again IMO) also much harder to understand and work with and Anim8or is more limited but also the easiest to use (IMO again).

Though it is possible to mimic this in Alice – make an invisible “bone” the vehicle for a visible sub-object – this is a bit difficult - and quite confusing when more than one or two sub-objects are involved. You also must place any motion limits on any bone/sub-object yourself and cannot do weighted parent-child links between a surface and multiple bones – a capability that is common (and needed, for elbows, etc.) in most dedicated animation programs.

Quote:
...all I would have to do is 'rig' the mesh and add actions ...
The biggest problem with this approach is just the size of the project – not Alice’s basic capabilities. For example, an animation development tool based on the Doom3 game engine, http://www.fountainheadent.com/n.x/f...on/Version%202 , supports probably four dozen different actions (including variations) for each character – and this is for a “simple” first person shooter game. To try to duplicate this in Alice, you would need to develop a similar number of methods for each character. Maybe possible – assign one or two methods to each student in a fairly good sized class – but certainly non-trivial when you consider each method also needs debug and testing.

In the same way that it would be nearly impossible (and certainly foolish) to try to do a large software project with the very minimal system development environment capabilities of Alice, a large animation project is also well beyond it’s intended use – though it is well set up to teach the principles involved in both cases.

As I reread this, it has a fairly negative tone – which wasn’t my intent. I really think what you are contemplating is possible if you have realistic expectations for the results. But there is a large danger that students may have very unreasonable expectations – you are not going to create a modern video game using Alice! (You can do a nice job on Asteroids and Space Invaders – see some of the games in the world section of the forum – but this isn’t the ‘70’s or even the same century.)

Quote:
HOw is the done with the models that come with alice such as the skater?
One final note. Shadow Sovereign did find a way to import new shapes into an object’s hierarchy – see the thread http://www.alice.org/community/showthread.php?t=570 . Again, this gets very tedious for a large number of objects but it is a good way to add/replace one or two meshes on an existing object. (I suggest you keep all the original meshes and just set them to “not shown” – otherwise you may have trouble saving the new object because of the missing parts.)

Good luck - I hope you are successful in whatever you do try.
   
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