On Mittwoch 27 Oktober 2004 22:18, David Culp wrote:
> The current AI objects are not solid, so landing on the carrier is
> impossible until we solidify the deck.  One way to do this will be to
> define the deck(s) as a set of rectangles; I think two should do it, but
> maybe more.  When the user aircraft gets close to the deck (using radar
> range and altitude) the AICarrier will start checking to see if the
> aircraft is within the area bounded by any of the rectangles.  If so the
> current elevation will be overridden with a call to
> globals->get_scenery()->set_cur_elev(deck_height). I haven't done this yet,
> but I think it would be better than trying to manipulate the hit list.
I guess that this is not sufficient.
We need to know at least the speed of that patch.

But even then, our current state where the physics depend on the framerate is 
not really a good thing.
Let me elaborate: The physics of our FDM depend on the ground level below the 
aircraft. But the ground level is only computed every frame. So The ground 
level is more accurate with different frame rates. The bad effect of this 
could be seen if you try to start on a runway with a slope. You will see the 
aircraft moving below several ten centimeters below ground depending on the 
framerate, speed of the aircraft and slope of the runway. Just because the 
FDM takes the runway level at the location we had some time ago. If this is 
significat lower you will move below ground.
That effect will be even worse if your deck will move. May be it will move at 
some day with rought sea. The FDM will see then groundlevels varying with 
more or less big steps. The smaller the framerate the bigger the steps.

I am all more for physics which is invariant with respect to changes of the 
If we put the decks and wires into the scenegraph together with some 
information how they move with respect to the earth, we can compute the 
location of the deck at any time.
To make the intersection teste less computional intensive I build up a small 
cache of the environment around the aircraft. The benefit is that we can 
request ground level and speed of the triangle below the hook/gear at any 
location. Carrier operation will be possible. Starting on a runway with a 
slope will work (The swiss glacier pilots might be thankfull :) ...
We can even model the influence of different ground types (A B52 will not well 
taxi on grass...).
We can make the beaver model work, since we know when we move on water.



Mathias Fröhlich, email: [EMAIL PROTECTED]

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