On Wed, 22 Dec 2004 14:21:44 +0100, Bert Freudenberg <bert at impara.de>  
wrote:

> Am 22.12.2004 um 09:02 schrieb Blake:
>> The Lunar Lander project I have in mind requires the ship to be able to  
>> actually change its heading, but I can't just use the forward script,  
>> obviously, because the effects of gravity have to be considered.
>
> That sounds overly complicated. Adding in gravity is just accelerating  
> along y, right? No heading needed for that ...

Adding in the gravity isn't the problem. Adding in the thrust is. Changes  
to momentum along the X and Y axis caused by the thruster are,

I could get the same ultimate result, I think, by moving forward and then  
pulling the ship down--but that would look terrible, since the two motions  
would be discrete, creating a step-like appearance when the ship is  
travelling up and to the right.
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Unless I miss something.