Re: [stella] Have kernel, need game!

Subject: Re: [stella] Have kernel, need game!
From: KirkIsrael@xxxxxxxxxxxxx
Date: 22 Jun 2003 13:57:40 -0000
> So you mean there should be no additional inertia then? Ok, not from
> accelerating the blades (clever concept, never thought about that). But
> doesn't the engine (turbine) need to increase its power when the angle
> is changed to lift the helicopter? And then we would have the inertia
> again, wouldn't we? 
> I think the blades also should work more effective when the helicopter
> moves faster. There are a few helicopters that can fly loopings and AFAIK
> some do that without wings. And they always seem to do that at high
> speed, so speed must have some influence on the lifting rate.

To summarize,
I think there are two simplified models you could use that would make 
a fun, doable game:

SFCave like (and yeah is a very
pretty port of the concept): horizontal speed is contant (or gradually
increasing; out of the player's direct control anyway).  Gravity constantly
adds a fraction to your downward speed, pressing the button subtracts 
from your downward speed.  (So sometimes it might take a bit to stop
going down and head back up.)  In this model, I don't think a spinup
time for the rotor would add to the fun, it would just needlessly add
to the difficulty of getting the copter to rise up.  (And it doesn't 
have to be a ribbon...actually, SFCave's scrolling is such that they 
don't erase the 'tail' of the craft, and I think they call it a ribbon...
actually it's a pretty neat visual effect, but I think they get it "for
free" because of their type of scrolling, they have a buffer to play

The second physics model is more complex, like I put that diagram
together for; the copter can be pitched forward or back.  In this 
model, gravity is always down, but the blade's thrust is always 
perpendicular to the roof of the copter, so it's usually divided
between fighting against gravity and moving the copter forward 
or backward.  Here there's vertical AND horizontal intertia. 

The hard part of that is :
A. displaying the copter at various tilts
B. for each tilt, how much is being added/subtracted to horiz speed, 
   and how much is being subtracted to the downward speed

Though B could actually be a small pregenerated lookup table, rather
than complicated angle-based stuff, so maybe it wouldn't be that tough.

But getting into the physics of the blade calculation is overkill.
However, in this second model, the game might be easier if you could
let go of the button and stop the blades. Maybe the blades could take a
while to stop adding thrust, but I don't think it adds a lot to the 

Sorry to drive this into the ground (so to speak)

   "There are more things in heaven and earth than are dreamt 
    of in your philosophy...   ...because your philosophy sucks." 
                 --Lore, "more things", brunching shuttlecocks

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