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Aiport Choose Signals

Started by Colin, August 23, 2010, 12:25:42 AM

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Colin

I've come across a small problem with airport runways. You can make a plane land and take off from two different runways, North and South but you can't make them choose between multiple runways, say two North and two South. If you have a lot of planes and the existing Loading Bays are full the other planes will just stack up and fly in circles above one runway.

I suppose one solution would be to designate different Loading Bays to different runways. (Just thought of that). Nah! forget that, it can't be done without making two airports.

This is not related to the Stop and Direction indicators.

Incidentally, the white arrow indicators need a detailed explanation on how they work. I've learned, at the cost of Mega congestions, because planes couldn't find a route. They don't seem to care which way the arrows point, but if you get one where the Taxiway crosses the runway, they wont move from the loading bay.
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Thought for the day

When you are up to your backside in alligators, it is difficult to remind yourself that your initial objective was to drain the swamp.

ӔO

I think of it more like a terminal 1, 2, 3 sort of deal, except each terminal gets their own dedicated runways.

there's a lot of clutter in this airport, but it's supposed to look like a real airport. Down to the core, there's simply One terminal for passengers and another terminal for freight and they're forced to go in a loop that doesn't overlap with each other.


It can be much more compact by taking out all the eye candy pieces.
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Colin

This is what I meant by different Loading Bays, but I didn't like it, much too cumbersome.
I may not agree with what you say, but I will defend to the death your right to say it

Thought for the day

When you are up to your backside in alligators, it is difficult to remind yourself that your initial objective was to drain the swamp.

Zeno

Quote from: Colin on August 23, 2010, 12:25:42 AM
I suppose one solution would be to designate different Loading Bays to different runways. (Just thought of that). Nah! forget that, it can't be done without making two airports.
Yes, it can be done in the same airport with the help of some signals, but actually you enroute your vehicles like if they were different airports. You have to divide manually by routing between the two different airport sections, just by assigning a route to any of the "Section 1" stops, and another route to a stop in "Section 2". Unfortunately, you can't make that two planes with the same route assigned choose different landing runways, depending on air traffic volume.

Anyway, here is an example which I usually build in my games: three runway airport.

prissi

YOu can use waypoints on the outgoing way on the airport.

Colin

Quote from: Zeno on August 23, 2010, 07:21:36 AM

Anyway, here is an example which I usually build in my games: three runway airport.


This is one way but it sure is ugly. No disrespect intended.

I think I'll try Prissi's 'waypoint' suggestion it seems like it might work. What would probably be better would be some kind of 'Choose' signal that could be placed at the beginning or end of a runway. Maybe this is not feasible. I'm no programmer.
I may not agree with what you say, but I will defend to the death your right to say it

Thought for the day

When you are up to your backside in alligators, it is difficult to remind yourself that your initial objective was to drain the swamp.

Zeno

I guess the problem is where to put the choose signal. The signal should be before the landing runway, just before the planes begin to fly in circles, so the behaviour is like if runway is busy, look for alternative runway. Unfortunately, there's no place between take-off runway and land runway to place such hypotetical signal :(

Correct me if I'm wrong, but I think at the moment different schedules/lines are needed in order to make the planes take off or land in a specific runway. That includes different stops, waypoints, etc.

PS: Now that I think on that, it might be possible to use choose signals (if existed) for taking-off runways, am I right?

prissi

The plane tries to find a free path when cycling. But it will not start way a search, because this is way to expensive and will freeze the plane in the air if not limited to a very small radius.

Fabio

The plane could search and cache all the possible runaway paths before taking off and, while circling, just test the first one to be free.

VS

Isn't way search for planes almost "free", in terms of resources? There is nothing to search except for airports, the air is "empty", no?

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skreyola

Perhaps there's a way to solve this without adding to the overhead.

Picture this: a skybuoy button adds air-waypoints. The waypoint can't be added to a schedule until the user clicks on it with the magnifying glass tool. When the user clicks on it, a dialog opens like the create schedule dialog, allowing the user to "connect" that waypoint to one or more runways. Then, planes can have that air-waypoint in their schedules, but the air routfinder will only look (when a plane reaches that waypoint either first time or as part of its holding pattern) at the runways connectes to that waypoint to see if they are free. This can also allow the user to choose where the holding pattern occurs.
Garbage collection code can remove the air-waypoint when all its runways are rendered inoperable, or sanity check code can forbid bulldozing runway that is connected to an air-waypoint.
Since this basically doesn't exist as an object in real life, it could be represented in the game by an ATC tower (there's already one or more graphics, at least in pak64), and all it would take to integrate that graphic to this idea would be to make it buildable outside a station... or else the air-waypoint would have to be above an airport... the planes should go to that square plus some height factor)

How hard would that be to code (1-10, 1 being toss together in an hour and 10 being never gonna happen)?
--Skreyola
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prissi

You can add waypoints to air schedule. If you do this correctly, you can force on or the other runway. But this gains nothing: The wayfinder must find a way from the parking position to the runway. This can be only done in a step, thus the plane has to stop there until a step occurs (about every 200ms). This is really ugly, it was present in old versions.

Colin

Why not just a tall tower/pole with a choose signal on top. and code the plane to look for it. Pretty much like a railway train does. It would not have to be too tall, after all, the planes only 'fly' in simulated space.

This could apply to choosing a take off runway too.

Planes will not, at the moment, choose anyone one from two parallel runways even if the runways are linked together with a taxiway. they will always take the first runway.
I may not agree with what you say, but I will defend to the death your right to say it

Thought for the day

When you are up to your backside in alligators, it is difficult to remind yourself that your initial objective was to drain the swamp.

prissi

Choosing involve route search. Route search cannot be done during display but only roughly 5 times a second => for any route search, no matter how dimple, the plane has to stop in midair for a moment.

ӔO

#14
You can also lay out the airport in the reverse order of what zeno posted.
The one ways on the tarmac will allow the planes to choose which stop to go to, but will force them to use one of the two exit runways.


It's not unusual to have passengers use one part of the airport, while cargo and mail gets another part of the airport, with each having dedicated runways that don't intersect. Also not all the runways are in use all the time. Outdated runways or runways being serviced don't get any use unless there's an emergency. Longer runways are normally dedicated for heavy international flights, while the shorter ones are intended for lighter aircraft, like commuter planes.

example would be O'Hare international, that has 7 runways, but not all of them are in use and there will be new runways that will run in parallel as the airport is expanded, and so that there aren't any dangerous intersections.
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Colour safe chart:

Colin

This is the way i like to put them, but if it's unworkable so be it.
I may not agree with what you say, but I will defend to the death your right to say it

Thought for the day

When you are up to your backside in alligators, it is difficult to remind yourself that your initial objective was to drain the swamp.

skreyola

Perhaps planes could check to see how many avaialable runways an airport has (or the airports could keep track of it) if the airport has a control tower, and cycle through the available runways, so that each runway will get used, and perhaps there will be fewer pile-ups in the holding pattern?
--Skreyola
You can also help translate for your language with SimuTranslator.

Lawyer

I was thinking about this lil' problem 'plane routes to land' and the follow possibility occurs to me:

1. If plane routes are automatically build in a manner that they always pass above the control tower (CT) before land;
2. If the head of multiple landing strips (LS) could be connected to the CT in a way that CT act as a signal that lead plane pass to the closer free LS;
3. Then planes will be able to choose between LS.

This way, plane routes could be build by choosing the CT instead of the loading area. The CT will guide the plane to a free LS and, subsequently, to a free loading area. Is this feasible?

EDIT: By 'connecting LS heads to CT' I didn't mean a physic link, but a sort of occult vector to trace the landing route.
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prissi

The problem is not to define a point of choosing. Any plane will decide cycling or not 16 fields before touchdown. The problem is, that ANY search for a free way to a stop MUST be done in a step, which will freeze ineviteably the plane for up to 200ms in midair. No buts, this is the situation.

Route search is easy, be will take some time. Since the route finder can only handle one vehicle per intervall, a route search must be finished before the next vehicle can do. Thus route search is only handled during the "step", one vehicle at a time => air planes hanging in midair waiting for route search.

I tried it and it was ugly.

Lawyer

#19
Ok.... there goes my bright idea... :(

Got it. the problem does not stand with the ability of the planes to choose a path, nor with the way they do it, but with the in-game mechanics to do it. I though it would be possible to make planes choose path to land like land vehicles choose loading platforms (i.e., choose platform signals), when they 'see' what platform is free without stopping (provided there is at least one free platform).

You are totally right: planes stopping in the air are ugly. Changing planes' routes when they are flying can confirm it... ;)

EDIT: At least the discussions about how to better arrange airport strips provided us with some nice pictures. Some ugly too.
offtopic: BTW, I noticed this '200ms freeze' when trams are passing through way-points. I didn't stop to figure why, but I guess it's because the way-points are too close, or because they are in squares with multiple possible ways. Not sure.
Creia no que quiser, mas não acredite no 'Fator Deus'
Believe in whatever you want, but don't believe in the 'Factor God'.
http://bulevoador.haaan.com/2010/07/04/o-fator-deus/

felo

Can not place the signal of selection in the taxiway?

In this way the airplane on the ground and may take time to select the stop.

Lawyer

Well, yes, but planes use only on strip to land, no matter how many you've placed on the airport. It seems that the only effective solution is to separate strips and loading bays according to routes.
Creia no que quiser, mas não acredite no 'Fator Deus'
Believe in whatever you want, but don't believe in the 'Factor God'.
http://bulevoador.haaan.com/2010/07/04/o-fator-deus/

Colin

Quote from: Lawyer on November 12, 2010, 09:21:54 PM
Well, yes, but planes use only on strip to land, no matter how many you've placed on the airport. It seems that the only effective solution is to separate strips and loading bays according to routes.

If you mean, a separate loading bay and taxiway to a each runway, I've tried this and it works but, it takes up horrendous amounts of space as each runway has to be 3-4 tiles longer than the proceeding one.
I may not agree with what you say, but I will defend to the death your right to say it

Thought for the day

When you are up to your backside in alligators, it is difficult to remind yourself that your initial objective was to drain the swamp.

merry

Well, London Heathrow (LHR) manages with 2 runways - one for takeoff, one for landing. 5 terminals, a large number of gates, and a continuous stream of planes in and out. So do we really need any more in ST?

I don't often use air transport, as my games are limited in playing time (I have limited time) and I rarely get to the point where it's a useful mode, but I've found in the past that the runways are not the bottleneck if you have one for 'in' & one 'out' (easily implemented). Maybe this hints that air transport is not the only solution for high volume long distance travel...