Zezo forum: Island's coordinates

Island's coordinates

Post by NumeroDixTV | 2021-02-23 | 19:25:38

Hello guys,
Do you know how we can find the coordinates of the islands for a race like rorc600 ?
The leaders seem to know perfectly how to place their waypoints around the islands.
Thanks and gl !

33 Comments

Post by SlyStarLeRetour | 2021-02-23 | 21:16:36

you have them on the map of the dash

Post by YourMomSA | 2021-02-23 | 21:48:06

The coordinates of the buoys are there, but not the islands. I don't know of a way to get the coordinates of specific points of land within the game. I just set the waypoints as carefully as I can, at maximum zoom... With a little extra margin if I'll be asleep or otherwise offline.

Post by BooBill | 2021-02-24 | 01:50:18

If you check my track on Dashboard you can see that I extensively explored the limits of navigable water on the south shore of Saba last night. Hint, the limit is nice blue water in the game graphics.

Post by zezo | 2021-02-24 | 05:59:26

I hit that beach last year. Was in the top 10 at the corner and put the waypoints a pixel away from the sand. Did not work.

This time I set my waypoint #2 very carefully, 10 meters N of ... buoy 10 instead of 2. Checked 5 times that I clear it. I saw that the pack is sailing 5 degrees to the left one hour later.

Post by gushami | 2021-02-24 | 14:10:39

Top sailors; How do you makeuse of the dashborad map and setting WP?
I ran aground in C600 but according to this I think I shoulf have cleared it.
Here is what it looked like in Dshboeard map
Aground

Post by Hardtack | 2021-02-24 | 14:54:34

I'm not a top sailor, but I know how the Dashboard map works :-)

It helps you set waypoints at marks that are not on land (according to the VR map).
You just tweak the waypoint until it is as close to the mark as you can get.
This works because the mark and waypoint positions are consistent with each other, and their relative position is correctly reflected on the Dashboard map.

However, the position of land features is NOT correct, because Dashboard uses a different map than VR. If a waypoint is at sea according to the Dashboard map, it may be on land on the VR map.

Post by gushami | 2021-02-24 | 15:01:41

Here is a better shot: Screenshot

Clearly most of of you did go even closer than I did, right?
So, what am I missing?

Post by Hardtack | 2021-02-24 | 15:26:27

As far as I can tell you were closest to the SE corner of the island. There was only one boat closer and its track 'ended', similar to yours, underneath the green boat.

If I read the track marks correctly, you ran aground at 13:44:28Z. You probably did not turn 180� immediately, but you turned east 90� at 14:07:00Z. For some strange reason this did not happen at the last reached position but slightly SW.

Interestingly I noticed that Luxair and Buddha missed the invisible checkpoint (10.18), but it's marked engine=true! So far we assumed that this would cause the boat's rank to drop and would also prevent the boat from finishing. However, Buddha is currently still ranked #1.

Post by gushami | 2021-02-24 | 17:30:31

Hi thanks for looking at it.
I didn't have raw log on but here is the race log at the time
Racelog

It confirms me hitting rock at 13:43, trying to get off with 97� at 13:56 and again 117� at 14.06.
Wp set at 12:57 was:
Actions: WP: 16�20'00.35"N 60�59'51.58"W; WP: 16�20'37.57"N 60�59'59.71"W; WP: 16�22'25.72"N 61�01'30.14"W;

So why am I at 16�19'52.24"N 60�59'56.67"W when running aground at 13:56?
Going betwween WP1 and WP2 should not have brought me there. Did VR take WP3 in the calculation before I reached WP2?!!!
Here are position, buoy and WP plotted manually
Plotted

I'm fully awared that trigonometry may prove me wrong but wanted to write it down anyway.

Post by gushami | 2021-02-24 | 19:31:10

The funny thing is, using the DB map after setting my WP's, I first thought I could have gone even closer but I left it as it was for safety's sake.
Anyways, looking at the Charts I think I found the coral reef I hit.

Post by BooBill | 2021-02-24 | 19:47:13

The extent of land at the SE corner of Desirada is clearly further out in the game map than it is in the Google map that Dashboard uses. Looking at Navonics charts, there is a shoal that extends out a good 400m. In real life, you definitely would have been on the rocks there. Also, looking at the tracks in Dashboard of the boats I follow, at least 3 appear to have grounded. All, in the resolution of the game, would have sworn they were on exactly the same line as everyone else. They probably were just a meter or two inside or bore off just a few meters earlier. That kind of indicates that this was very close to being a mass pileup. The story of my grounding at Saba is the exact same. I have all the same screenshots you do that show me well clear of land in both Dashboard and the game map. However, I did head up just a teeny fraction sooner than others.

Moral is, the precise limits of the game map and Google maps are unreliable. You've had some of the top sailors speak up here and frankly, there is no secret, other than to give it a little wider berth than you think is necessary, or be prepared for the consequences.

Post by gushami | 2021-02-24 | 20:17:25

Yes, I'm going back to my old safer playing style after this race. I got carried away when I looked at some of the earlier roundings made by the leaders of the race.

Post by gushami | 2021-02-24 | 21:33:12

Still would like to know Tipa's secret though.
This one looks quite impossible.

Post by Hardtack | 2021-02-24 | 22:06:21

The most likely explanation is, the tracks are simplified. This also explains why Luxair and Buddha seem to have missed the 10.18 checkpoint.

Post by gushami | 2021-02-24 | 22:56:43

I see, just like in the VR GUI.
Just thought for a while that the black dots were actual WP coordinates, taken from the race log.
Thanks

Post by Ventura_317 | 2021-02-26 | 19:59:55

Hum ! I dont think so !
Having my boat in stand by in the race I simulated this afternoon a test run on Buoy 10 .
I carefuly adjusted 2 WP the first practically on the buoy and the second down verticaly for a better reference and took a screen print .

Few hours later I checked my track on the Dashboard Map and compared it with the plan . No deviation at all ( the circle was a Dia 20 m ).

In addition , collecting my track in VR messages for the buoy #2 I crossed on the 22 /02 ( lat/lon from the data mentionning "wp" or "hdg" or "hdg-prg" ) I found it also perfectly in line with the plot on the Dashboard Map !

Conclusion: I trust the Dashboard track that means some players should have been disqualified as you commented in a previous post !

Regards

Post by Ventura_317 | 2021-02-25 | 06:18:09

Probably an MCES secret ( Right dot is LaMerNoire ) ! LOL

Post by zezo | 2021-02-24 | 20:24:59

Maybe we should finally reverse-engineer the game data and import it in the dashboard.

Data is actually straight forward - height map image. But It's compressed with something slightly non-standard and I could not decompress the images. But I did not try too hard, spent just few hours.

Post by BooBill | 2021-02-24 | 22:21:09

Is there any way to recover past WP data after you close your Dashboard? Appears I missed mark 10 after checking that my WP was 20m NW of the mark. Dash shows my track turning 20m NE. Dashboard tab closes automatically when you close the game tab and now I can't figure out where I'd actually set the WP. Probably a brain fart on my part, but I've got the lat and lon of the mark written on my notepad correctly, so I know I didn't have that wrong.

Would be hugely appreciative if you can extract the map data from the game Cvetan. I've blown so many races running aground.

Post by Hardtack | 2021-02-25 | 00:15:24

Storing waypoints would require a little bit bookkeeping. Probably just the race ID, but still. Not my favourite task ;-)

I spent some time trying to figure out the map data, but I didn't get very far.
I don't think it's compressed (except for gzip transfer encoding). The first bytes are the same as the numbers in the file path and name - most likely designating the tile size and position. I assume the remaining data is a list of map features in binary encoding but I might be totally wrong. It doesn't look like raster data, by contrast to the map I saw in a VR forum post.

Post by Sunkist | 2021-02-25 | 07:27:22

A good first try would be to compare the coast line with the GSHHG data set.
https://www.soest.hawaii.edu/pwessel/gshhg/
it comes in the 5 resolutions that reminds me of the game:
- full resolution: Original (full) data resolution.
- high resolution: About 80 % reduction in size and quality.
- intermediate resolution: Another ~80 % reduction.
- low resolution: Another ~80 % reduction.
- crude resolution: Another ~80 % reduction.

would assume the full to be used for grounding computations

Post by kalle | 2021-02-25 | 13:26:25

There must be someone who nows what kind of map the game is using. Luxair, Arylla and other top players normally clear the island...I wonder how they can get that close.

I can�t ;)

Have a nice day.

kallemans

Post by BooBill | 2021-02-25 | 13:58:17

Luxair and I both grounded at the same spot in the Azores during the Europa last year, so I don't think he has any magical map. Also, Tip and Buddha grounded on Redonda last night.

If I haven't grounded more than anyone in the last year, then I'm certainly on the podium. It's just that really fine line of pushing competitiveness too far.

I do think they have reduced the resolution on the maps from last year though. I'm also virtually certain that the underlying map used to determine if you are on land or water is not the same as the one used for the graphics. Most of my groundings have very clearly been displayed as still in the blue.

Post by YourMomSA | 2021-02-25 | 14:55:42

Toppen also has grounded a lot, and has done an amazing job of recovering to finish well. I've grounded plenty of times as well, but I've been pushing the limits a little less lately.

In the real world, my dad taught me decades ago that for starting a sailing race "if you're never over early, you aren't trying hard enough". This was in the context of very strong one-design fleets where being 2 seconds late can ruin the whole first leg of your race.

It's similar here. With thousands of identical boats... Hundreds of which are capable of winning, you have to push the limits if you want to win. So you see boats like Tipap, Buddha, BooBill, Toppen, and many others running aground trying to make small gains at every turn. And there are so many trying that a few will succeed to finish near the top.

One thing I've done a lot of is... In the record attempts like Jules Verne... Once I know I've completed my last run, I'll start again and go do some coastal sailing. Originally I was just doing it for fun, and I still find it fun. I'll sail through patches of islands and into deep corners of the world where races would normally never go. I just go and play. But over time, I realized that by doing that, I was building an improved awareness of what's safe and what isn't. Every detailed landmass corner will be unique in formation (as far as I know), so you can't simply learn a perfect rule... But you can gain a sense of it so that at least you usually aren't terribly surprised if you run aground. You can also gain a better sense of where the risk is higher so maybe you should either take less risk or be online, and when it's probably safe to sleep while sailing on waypoints. It's hard to explain in words. It's just a matter of building experience. And then realizing you'll still run aground occasionally anyway.

It's also important to do risk/reward analysis. Depending on how dense the fleet is around you, how you feel about risking a huge loss to make a small gain, and whether or not you'll be online, sometimes it makes sense to push the limits, and sometimes it doesn't.

I've wondered at times whether or not anyone has the game's land data. If anyone does, it isn't a lot of people. As discussed, most of the top boats occasionally run aground. But... years ago, during VRO2, the game had a flaw where their visual cartography was offset from their grounding calculations... so sometimes you could sail over the beach and other times you could run aground in open water. Not by much... But enough that it was awful in races like this. And there were just a few boats... Like maybe 5... Who somehow knew where they could safely sail across beaches. But... it could just be that they got a sense of how the offset was occurring, offset their own navigation accordingly, and were a bit lucky as well.

Anyway... I'm personally divided about whether or not having the land data in Dashboard would be a good thing. Certainly it would be nice to be able to go offlne knowing your boat is safe... And if some competitors have it, then you kinda need it to mitigate their advantage... But it would also change the nature of the competition into something less fun, in my opinion. It would be more of a contest of Dashboard waypoint management than anything else. As it is, it's somewhat like racing in a real fleet of thousands of boats. To win, you have to sail close to land... Knowing if you push it, you might hit a rock.

Post by zezo | 2021-02-25 | 19:43:41

Well said. Probably one of the reasons I never went into reversing that.

Post by zezo | 2021-02-25 | 19:42:03

@Sunkist VR data is not GSHHS-based. My chart is.

VR data includes heights/depths as you can see on the map. When you select chart style you just change the color palette. Height data is the same.

Post by BooBill | 2021-02-25 | 22:23:32

VR data includes depth?

I had assumed it was either water or land. Certainly, there are places like in the Scillies that we go through all the time where if you look on an actual nautical chart you wouldn't get near. Now, the spot where I grounded off Saba and where Gushami grounded off Desirada were hundreds of meters off the real shoreline, yet not of navigable depth, in real life.

Is it possible VR is now applying depth and draught clearance?

Post by YourMomSA | 2021-02-25 | 23:59:09

I don't think depth matters for grounding. Just for color schemes.

Post by Sunkist | 2021-02-26 | 07:15:28

In that case they would have to provide depth charts and draught of the boats. ... I'd rather hope they implement waves / currents for offshore racing. Would add a nice level of complexity :D

Post by Hardtack | 2021-02-26 | 14:00:03

Cvetan is right - it must be a height map, and it probably uses some kind of compression - run length maybe? I wasn't able to make any further progress deciphering the data though. I could install Unity and examine their tile formats.

I'm divided about it just like YourMom. Not knowing exactly how far you can push actually puts a thrill in the game and it's one reason why I like races like the RORC Caribbean. On the other hand it annoys me to know that a handful of players has access to a precise map. In a Europe to Caribbean race two or three year ago, I don't remember exactly which, a player used a passage between islets that no one would have thought navigable looking at the VR map. I'd rather like to see VR provide an accurate map and introduce elements randomness in a more realistic way.

Anyway. We're not even sure that the client-side map is actually used for land detection on the server. Suggesting false security would be the worst thing Dashboard could do.

Post by YourMomSA | 2021-02-26 | 15:31:06

I'm not confident that there are players who have the data. There are so many good players trying to push the limits that in any given race, whoever pushes it the closest without running aground will look so good that it would be easy to think they have an advantage. But as long as it isn't the same boats every time (or a mysterious new entry every time), there's no particular reason to think they have the data. The gap in the race you're referring to was probably visible in a Google map, and perhaps it's just that with enough boats racing, it's likely that someone will take the risk.

Even in the case I mentioned where a handful of boats knew how to work best with the cartography offset bug in VRO2, I think it was probably a consistent offset (like... the UI was showing all land offset north by 100m, or something like that), and they just figured it out and navigated accordingly.

There's also a middle ground, between "so many boats are racing that some will get lucky" and "a few boats have the actual data". That middle ground is... spending the time to scout it out. I mentioned this earlier, as something I do casually for fun. I've never invested time to take notes personally about the detailed locations of landmasses, but... some people may be doing that. For example, I've observed one boat right now using his Jules Verne boat to repeatedly ram Ile de Re's West end. I believe he's proabbly trying to note its exact coordinates for personal usage during Solo Maitre Coq. That's a lot of work, but there's nothing unfair about it.

Post by gushami | 2021-02-26 | 16:11:48

I'm also divided. At the end I think immersion is more important than precision.
But I want to know what matters and what's not. If depth/draughts are in the game I want to know. I don't need the exact numbers. If I like, I can study depth charts and make assumptions about the draught of the boat to make my own risk/reward decision. Just don't want to imagine choices that has no impact in the game.

Post by NumeroDixTV | 2021-03-25 | 17:35:36

Since this post, I know for sure some players (including recent winners) have the exact same map data as the game. They have the shorelines worldwide.

I really doubt VR payed for this so I tried free shorelines on google, the ones from NOAA, but none is the same as the game yet.

That is definitly an advantage for them but I will keep searching :)

I also made the method Your Mom Sa described (crashing and writing coordinates) but it's a lot of work for a bad precision.