Facebook

Login

Support Sailonline

If you haven't already - join the SAILONLINE YACHT CLUB!

Please also consider making a donation - all amounts are greatly appreciated!

Board » Technical Discussion » Do All Boats Start The Same ?

Posted by
A2


Users avatar

Posts
347
Registered at
2009-10-26 00:39:42
2015-01-07 21:16:06 - Do All Boats Start The Same ?
Since the Free Turn artifact has been 'fixed' it brings to mind another starting issue that occasionally has been discussed in chat relating to the way boats appear on screen at the Gun. In the very beginning some boats seem to get out of the gate sooner than others. So I was wondering if this is indeed the case in fact or simply a lag in the way fleet positions are reported to the client.

From careful observation & astute deductive reasoning I am in the camp that believes the former to be the case. Which begs the questions what if anything can be done to get to the front of the queue. Also does the ranking of boats prior to the start of any race indicate the sequence in which the server will execute steering instructions on their behalf ?

Granted a single jump advantage early on is rarely decisive by the end of any race but it is a definite psychological boost when reaching the 1st mark or headland down the course.
None so blind
Posted by
hmm


Users avatar

Posts
118
Registered at
2011-11-03 13:35:22
2015-01-08 20:58:49 - Re: Do All Boats Start The Same ?
The short answer is that all boats start at the same time if they have set a starting command.

The sailing engine which takes care moving of the boats has been written by Jakob and Kalle, the original founders of SOL and I can't say I know it thoroughly. This is my best explanation on what happens though.

Practically what happens is that the server calculates boat movements one boat at time and when starting there are hundreds of boats starting at the same time.

There is no particular order in what the boats are moved, it happens in the order the underlying database SOL uses happens to list them. I suppose databases tend to internally provide data in same order which depends on how it's internal data structures stores the data, it can be related to the order data has been written in the database but not necessarily always so.

When the moving happens in sailing engine there is a separate program handling the caches. Every 30 seconds it will take a snapshot of every boat's position and store it to server memory. When SOL clients connect to server for asking the fleet position this snapshot is what they get. This is to prevent the need of every client individually asking from the database the positions of all boats.

When this snapshot is taken, it can happen when the sailing engine is in the middle of moving the boats so in the image you can see some boats further than others. In my opinion this explains most of the differences you can see in boat movements just after start.

There might be more things affecting the issue (I think the sailing engine has some kind of method where it will detect high load situations and move boats less frequently) but to me the sailing engine is good enough and at least I don't know any way to always get a "front line start".

Posted by
Rod


Users avatar

Posts
392
Registered at
2010-06-24 22:30:48
2015-01-09 13:50:57 - Re: Do All Boats Start The Same ?
In the practice races, I have almost always observed that boats starting at the same time, and following the same course, (at presumably the same speed), will maintain the same order until the first rounding, (15 min or so later). This would suggest that the server maintains a list of boats, and moves the boats in the same order, at least until the list is disturbed by different orders being given by the helmsman.
If it breaks, it's not strong enough--if it doesn't, it's too heavy.
Posted by
Bimmer


Users avatar

Posts
447
Registered at
2015-02-23 15:38:27
2016-03-08 08:49:05 - Re: Do All Boats Start The Same ?
Hi Rod
In practice races it is the boats distances to the next waypoint in the actual race that is measured and can be seen on the ranking list, and not the marks we use in PR, so you have to trust your eyes here :-)

Bimmer

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

Cape Town to Java 2025

Get ready for an exhilarating new challenge as we set sail on the eighth leg of the 2025 Ocean Championship Series! Reversing the 18th century footsteps of the indentured Cape Malays that inspired Isna Marifa’s moving novel known 'Mountains More Ancient' , this leg takes us from Cape Town South Africa to the Bay of Belbuhan on the south west coast of Java - a 5100 nm journey of endurance, strategy, and pure sailing adrenaline, aboard the 125 ft Orange catamaran. Do you have what it takes to conquer the Indian Ocean? Join us and put your skills to the ultimate test!
PRIZE: SMPF
Race #1937
INFO by brainaid.de
Orange 125 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ3 - OCCH - SUPSOL - SYC
Race starts: Aug 04th 11:00 Registration Open!
▶ Flash
GO TO RACE

Lago Viedma Ice Race 2025


Less than one third of the land mass of the planet is to be found in the southern hemisphere, and most of that in tropical to temperate latitudes or in Antarctica, so it is difficult to find good natural ice to race DNs anywhere in August! However, if you take an internal flight from Buenos Aires to Aeropuerto Internacional Comandante Armando Tola de El Calafate by the shores of Lago Argentino, it’s only a 100km taxi ride to Lago Viedma, where we have set out a few beacons on the ice for you for a quick 80nm blast around the four corners of the lake, and as it’s so remote here, no need to worry about breaking the solitude of monks or suffering PL!
Race #1852
INFOby brainaid.de
DN PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: DN - SYC
Race starts: Aug 03rd 09:00 Registration will open soon
▶ Flash
GO TO RACE

Tall Ships Races 2025 - Kristiansand to Esbjerg


Welcome to the fourth of four virtual Tall Ships Races in European waters which are concurrently being organized in-real-life by Sail Training International . This fourth race is from Kristiansand in Norway down Denmark’s North Sea coast to Esbjerg; circa 150nm in Sailonline’s magnificent 90m Barque.
NOTE: Starts and Finishes in tall ships racing are always offshore to avoid conflict with shipping and shipping lanes; online and real-life may not match exactly.
Race #1926
INFO by brainaid.de
Barque 90m PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: TS - SYC
Race starts: Aug 02nd 16:00 Registration Open!
▶ Flash
GO TO RACE

Marstrand to Cowes 2025


We invite you to another race, which will kick off the third quarter of our ARCH series. We'll set off from Marstrand, Sweden, which, along with Skagen, Denmark, marks the line commonly recognised as the border separating the Baltic Sea from the North Sea. The 650nm route will take our Ripitide 50 across the North Sea and the English Channel to Cowes, England. Watch out for the fast ferries crossing the Channel from Calais to Dover 😊.
Race #1935
INFO from brainaid.de
Riptide 50 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
ARQ3 - ARCH - SUPSOL – SYC
RACE CLOSE: Wednesday,
August 6 at 2300 UTC.
Race starts: Jul 28th 17:00 Registration Open!
▶ Flash
GO TO RACE

Sinbad by Balloon 2025 - Baia de l'Oiseau to Carnarvon


How ever shall I return to report with clarity to my Great Sultan – asked Sinbad. It needs be told this island and all its fables shall be expunged from the annals of every thousand and one night. The wind howls – and sun be none (it’s Winter, Sin’bro, ed.) – and all days from the west, but let’s launch anyway and see if we can work our SOL Balloon north as the days pass aiming for Asthralaya, where The Mahabharata tells the ancients once tested mighty weapons, about a quarter and a million qasbah away (2500nm, ed.), perhaps one month.
Race #1885
INFOby brainaid.de
SOL Balloon PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC - SBB
Race starts: Jul 23rd 11:00 Registration Closed
▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member WRmirekd
  2. Sailonline Yacht Club Member CriticalHippo
  3. Sailonline Yacht Club Member vida
  4. Sailonline Yacht Club Member Kipper1258
  5. Sailonline Yacht Club Member rafa
  6. Sailonline Yacht Club Member KaSToR
  7. Sailonline Yacht Club Member BRENTGRAY
  8. Sailonline Yacht Club Member rumskib
  9. Sailonline Yacht Club Member Sax747
  10. Sailonline Yacht Club Member YANN

View full list

Series

Mobile Client

SYC members have the benefit of access to our mobile/lightweight web client!

The mobile client