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Navigation

Posted: Tue Jun 21, 2005 3:03 pm
by Jos Elkink
I'm looking for some suggestions on a specific subject. Currently the only way a ship knows where it is is by keeping very precise track of all changes in course and speed. This works quite well - a character of mine used to have a pretty decent map of the sea between the two oldest English islands - but is also slightly awkward.

Of course, the actual location of the ship is stored in the database as an x,y coordinate. But it wouldn't be cool if players could see those actual numbers when sailing. It's not 'relative' enough and it's too weirdly precise.

What would be alternatives? What kind of instruments are used in real and what kind of information do they give? What would be a nice equivalent in Cantr?

Note that I would like to someday introduce drift thanks to weather / wind, so it will eventually matter :) ... (This is long term planning, though.)

Posted: Tue Jun 21, 2005 3:15 pm
by west
I don't know of too many characters who actually keep track of where there ship IS while sailing...most I know either hug the coast or follow a set route each time they go somewhere. When on the open sea, I just point in a direction I know there's land and wait until I see it; there's no real way of knowing where in the middle of the ocean I am.

A sextant (and ship's clock) was formerly used for measuring latitude and longitude. It's possible you could implement some latitude/longitude lines that have some correlation to the x,y's. Of course, each seafaring civilization measured their longitude differently, depending on where their prime meridian was (paris, greenwich, etc)

Posted: Tue Jun 21, 2005 3:27 pm
by Jur Schagen
Determining the width should be pretty easy... measure the height of the sun in relation to the day of the year and the time of day, and you know your "width" degree (the North/South part of your location, or the Y-coordinate) pretty accurately from the 15th century onwards, I think. Historically, a "sextant" (Dutch word; don't know the English translation) was used for this and it was very accurate. Of course, when you introduce this into Cantr, you're imlicitly also introducing a "sun"... which is a continued subject of debate ;)

Determining the length degree was much more of a problem, and was only tackled when accurate time measurement relative to a fixed point (i.e. where you started your travel) was possible independently of the position of the sun. Subtracting the "sun time" from the "origin time" could tell you the length (the East-West part of your position, or you Y-coordinate).

For Cantr, I don't think implementing this is very wise, because it invites too much for OOC information to be used IC. Wouldn't it be an idea to set your own "waypoint" (like your city of origin) and then "see" the angle and distance to that waypoint?

Jur.

Edit - Ah, West beat me to some parts...

Posted: Tue Jun 21, 2005 3:44 pm
by Jetlag
Almost all real-world navigation is based on either knowing how far you've travelled in what direction (the current Cantr method, essentially) or referencing your current view of astral bodies to maps and charts. Cantr doesn't (currently) have any kind of information on how the sky behaves, and something along those lines would be necessary for that kind of navigation. It wouldn't necessarily have to introduce a sun, though, as it doesn't need that level of detail (we don't have to specify exactly how we pump bellows to get smelters to work, so why would we have to specify exactly how we're studying star charts?) and besides - who says the Cantr sky isn't full of stars that never change positions relative to the ground? And I know that different cultures would, in the real world, develop different ways of measureing lattitude and longitude, but they'd also come up with different ways of measuring time and Cantr all runs on the same clock, as far as I'm aware.

Sailors would have to have some kind of measuring device (astrolabe, sextant, etc) and charts giving information on the stars. Using both would allow a navigator to pinpoint where they are, to a given degree of accuracy. It could work as a project taking one hour and requiring both a measuring device and a chart. Depending on the acuracy of both the chart and the device, their x,y location could have a varying degree of accuracy, which could be implemented in the same way as the variation in exactly how much of resource R you can gather in an hour. For example, if they have a basic star chart and an astrolabe, they could get a value that's a random deviation of up to thirty miles away, whereas a sailor with a detailed start chart and a sextant would get a value that's within five miles (or days' sailing, or whatever) of the correct, accurate location. Multiple projects would all come up with slightly different answers, even if the boat hasn't moved at all, which could help find a more precise location.

As a complete alternative, what about bouys? Perhaps it would be possible to create bouys at given locations on the sea, which act as signposts? If someone has set up bouys to mark the route from one island to another, the path would be marked for any future navigators to follow. If one can be seen, a boat can be set to sail to it in a similar way to docking with a port.

Posted: Tue Jun 21, 2005 3:49 pm
by rklenseth
Back in ancient times, navigation was done by the stars. Thus why astronomy and astrology were serious science back then because without them travel would have been almost impossible especially by water. Many different instruments were used back then but I would have to look them up in order to name them all and what they were used for.

Posted: Tue Jun 21, 2005 4:20 pm
by T-shirt
Speed and direction are essential to be able to calculate where you are from your starting point. Direction is given very accurately. Speed is given in a percentage number. How far you travel in a day with a speed of 100% depends most likely on different factors, like what kind of ship you sail. Still the player is only given this 100% factor and not a 'pixels/hour' number or something equivalent. When this number is given, free of charge to every captain or only to those who make a speedmeasuring machine, it will be possible to calculate you exact whereabouts.

Posted: Tue Jun 21, 2005 5:20 pm
by Jos Elkink
T-shirt, your idea would not work if there is also drift implemented, so your ship would move other than the direction you told it to. This drift is not currently implemented, but it would be nice to have a navigation system that would work also with drift.

The other ideas are quite useful. I made it sound as if I had no clue about how it worked in real life, but I actually do. I'm more interested in the suggestions for Cantr, and there are some good ones. I like the idea of measuring position relative to the starting position. You could imagine some kind of instrument that you can reset anytime and that will later tell you the direction and distance to that point from where you are, perhaps with a random deviation indeed. That's a pretty cool idea. There's one small issue I'll have to discuss with Jur, but the idea is good.

I also really like the buoys idea :) ... It's a separate issue, but definitely should be implemented. Would work very similar to lighthouses, just visible only from a much shorter distance. Cool idea :) ... Should everyone be able to remove them, also? :)

Posted: Tue Jun 21, 2005 5:42 pm
by rklenseth
How about a knot system to figure out how fast you're going? And then have a tool to measure the distance to the horizon?

How about trade winds that could change with season? Different sails can be made to deal with the winds. Later they could be replaced by steam engines and then later by nuclear reactors.

Posted: Tue Jun 21, 2005 5:50 pm
by rklenseth
The tool used to measure where they are was called a Sea Astrolabe. It measured the altitude of the Sun compared to meridan. During the night, sailors relied on the stars and their position in the sky in order to tell where they are. There was any special device used for the stars. You only needed to have the knowledge of where certain constellations were during specific season.

If we ever have night and a day. Perhaps we can set up a sky with stars in it. Then people can create astronomy. I think this would be easy to do. Create a layer over the entire Cantr world of stars. Then have that layer move over the sky during the certain seasons. We can have this work sort of like how we can see where our location is on the map. When you look at the sky, you'll get a image of the stars that you can see in your area.

Posted: Tue Jun 21, 2005 5:51 pm
by Snake_byte
Woe woe lol. You need to slow down! :lol:

Posted: Tue Jun 21, 2005 6:10 pm
by Talapus
Although I like the idea about implementing a night sky (even though people who know about astronomy OOC will be the only ones to invent astronomy IC), perhaps we could just adjust the current system such that when you travel by boat, your course is off by a deviation of up to 10ยบ unless you have a sea compass on board. If you have a sextant, then you will be given your current x coordinant (or y, it doesn't really matter on the cantr world unless the map actually has poles or some such, which I think it doesn't (my guess is that the map wraps at both sides meaning that we live on a doughnut shaped world). The clock would give you the other coordinate. These coordinates could either be absolute, or relative coordinates as suggested by someone else.

EDIT: until we can deploy GPS satellites, in which case we could just use that!

Posted: Wed Jun 22, 2005 2:28 am
by Nick
Well one thing that would make sailing more realisitic, is being able to see more things from a far distance. You should be able to see further when you're on a boat, than when you're on land.

Posted: Wed Jun 22, 2005 8:29 am
by Cookie
If you could make Bhouys that would help.

Nick wrote:Well one thing that would make sailing more realisitic, is being able to see more things from a far distance. You should be able to see further when you're on a boat, than when you're on land.


I think you already do see more on the location map. I'm not certain but I think it zooms out as soon as you undock.

Posted: Wed Jun 22, 2005 9:37 am
by Nick
Cookie Monster wrote:If you could make Bhouys that would help.

Nick wrote:Well one thing that would make sailing more realisitic, is being able to see more things from a far distance. You should be able to see further when you're on a boat, than when you're on land.


I think you already do see more on the location map. I'm not certain but I think it zooms out as soon as you undock.


I can say for certain that this is not true, and I don't know why you'd think so.

Posted: Wed Jun 22, 2005 12:27 pm
by Cookie
You can say for certain?

I undocked from somewhere not so long ago, before I undocked i could only see the black mark of the location I was at and after I had undocked I could see two black dots. Your cetain certain?