@devlin: personally I dislike video tutorials, I've lost count of the number of Blender video tutorials I've tried to follow and I still can't fathom the darn thing. I try my best to make my scripts easy to follow, and they all work in similar ways (I tend to re-use a lot of code
) so once you understand how one works the rest should be easy to figure out.
The main thing you need to have to do this sort of thing is a really good understanding of how spatial relationships work inside the 3d engine 'world', angles in particular are a real pig to get the hang of and the human brain has evolved to only think in terms of angular relationship in one frame of reference, i.e. the one where your head is 'up' and feet are 'down', that's why pilots get paid so much, being able to think in real 3d is difficult.
Here is an experiment you can try, pick up an object, say a pen, and hold it in a specific orientation in font of you. Now describe that orientation using numbers, the most obvious being x,y,z coordinates from some 'origin' (maybe the tip of your nose for example) and 3 angles (again from some frame of reference, maybe the floor). That bit is easy, now do the same with another object in the other hand, give it a completely different orientation and describe it in numbers, use the same reference point and frame of reference if you like). Ok so finally describe the position of the first object with respect to the second one, i.e. the position and orientation of the second object becomes the reference point from which you specify the the first objects position.
The reason this is important is that from code you not only need to be able to absolutely specify an objects position in real time, you also need to be able to calculate the position of other objects in relation to that object, for example if you have a helicopter model and a missile model and you want them to move around as one unit (until such point that the missile is fired) then you need to do that math every frame. If you have 4 missiles then you have to do the math 4 times every frame, once for each model.
Been there, done that, got all the T-Shirts!
