Open GL and objects (newbie question)

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Post: #1
I'm intersted in starting a simple Open GL app but I don't know much about supported objects. Now I know that Open GL doesn't have standard object type like QuickDraw 3D's 3DMF format.

What I wanna do is make simple objects (like the cars in the game Spectre Supreme) and use those to move and rotate in a 3D world.

I'm not too focused on the 3D world now, but I am more concerned about the object. Can I hard code them, and if I can is the drawing procedure similiar to Cocoas NSBezierPath (like, join points to get lines). Or am I better importing a pre made 3D object in some format.

Also, once I have my objects drawn, how do I animate them?

Thanks for your time

"When you dream, there are no rules..."
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Jeff Binder
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Post: #2
It's probably best to load the models from a file of some kind. Meshwork files are easy to load and can be created with the program of the same name (http://www.codenautics.com/meshwork). There's some sample code here on iDevGames for loading and drawing models in that format.

For animation, there are a few ways to do it. For a simple way, you have each frame as a separate mode. Then, when you draw it, you interpolate between the poses. For example, if the character is in pose 1 at the beginning of the animation, and in pose 2 after 0.5 seconds, you do this to get the vertices that you actually draw:
Code:
(pseudocode)
t = time / 0.5
for all vertices in pose1 and pose2
   drawnvertex = pose1vertex * (1-t) + pose2vertex * t
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