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 Support » PROTEST VINEYARD RACE

Page: 1 2 Next

Posted by
NZL_PaulR


Users avatar

Posts
311
Registered at
2008-07-22 12:21:30
2011-09-04 01:55:26 - PROTEST VINEYARD RACE
PROTEST First 4 boats look as though they have passed NORTH of The Cows. Yellow course line shows to pass The Cows to Starboard.

It may be the delay in updating tracks but is disconcerting at least!!

--- Last Edited by NZL_PaulR at 2011-09-04 01:57:20 ---
If it breaks, it's not strong enough!
Posted by
AGage


Users avatar

Posts
411
Registered at
2008-12-27 10:31:57
2011-09-04 04:28:00 - Re: PROTEST VINEYARD RACE
Nothing wrong with their tracks... 1 & 4 even have a few pixels to spare at max zoom...
I help develop the client interface for the best online ocean racing sim there is... __/)/)_/)__
Posted by
ShamrockPirate


Users avatar

Posts
189
Registered at
2010-12-03 17:49:57
2011-09-04 14:30:34 - Re: PROTEST VINEYARD RACE
Which brings up an interesting question.... Do buoy marks have the same characteristics as landmass? i.e. if you strike them, you go TWA=0? Or can they be "crossed over", like an SLI? I believe that if the servers sees the boat as rounded, it's all good, though it appears The Viking probably painted the Cows a different colour on the way by. ;>))

SP
Posted by
zero


Users avatar

Posts
120
Registered at
2010-02-07 16:56:30
2011-09-04 16:05:11 - Re: PROTEST VINEYARD RACE
I really don't see how can you foul the computer. Computers are great but they are dumb; if they are programed to allow some "event" to happen if and only if "x" is greater than "1", no matter how much you plea, you will not get the "event" if your x is 0.9999999999999.

I don't think you can pass "over" the mark and still be counted as "rounded", that would mean "x"=1, the software is probably writen as "x">1 to be counted as rounded-the-mark.

No, a mark in the water is just a point defined by it's latitude and longitude, meaning you cannot "hit" and be stopped dead in the water at that point.

Disclamer: I am not a programer and have no idea how the Sailonline code looks like.

cheers,
Antonio
Posted by
AGage


Users avatar

Posts
411
Registered at
2008-12-27 10:31:57
2011-09-05 07:52:05 - Re: PROTEST VINEYARD RACE
For x>1 you are correct zero, if you changed that to x>=1 then it is possible to have 0.999999999999999999999 return true for that (2nd) expression, due to the finite precision of machine computation...
HOWEVER - that is an extreme case.

I think it is technically possible to pass over a mark and have it count. Take an imaginary line that extends out from the mark - the direction parallel to that of a line which bisects the rhumblines to and from the mark... Now if you cross this line (which, while infinitely long, is bounded at one end by the mark) in the correct direction, a rounding is recorded. I do not know the exact code used, but in geometry on paper, if you hit the very end of a line (the mark in this case) it is considered that the lines intersect, ergo a fair rounding geometrically...

Consider though, that such small distances are really beyond the graphical fidelity of the client... At maximum zoom 1 pixel is still about 3 feet/1 metre - the scale indicator is 100 pixels long, and I have never seen it show less than 0.05 nm, which is almost exactly 1m per pixel.

Conclusion: Someone actually passing OVER a mark and having it recorded as rounded is an EXTREME EDGE-CASE, and would occur equally rarely (I doubt it has ever happened on SOL yet)... Ergo, it is not something the server should be programmed to deal with IMHO...

Also, as shown above, there is a 0.5m 'margin of error' in the pixels drawn in the client at maximum zoom, so from the client map it is impossible to tell if this actually occurred. Not to mention that the marks are drawn with 2px radius, so while only an infinitesimal point to the server, they appear as a buoy 4m in diameter on the map! (@max zoom)

Consider though, applying this to the finish line: if you hit the very very end of the line, should that count as a finish?
I think yes...
I help develop the client interface for the best online ocean racing sim there is... __/)/)_/)__
Posted by
zero


Users avatar

Posts
120
Registered at
2010-02-07 16:56:30
2011-09-05 14:03:22 - Re: PROTEST VINEYARD RACE
Thanks Aaron,
This is all very interesting.
My limited knowledge of programing stops at MS-Basic.
Antonio
Posted by
NOR_Jawik


Users avatar

Posts
70
Registered at
2008-08-31 20:55:18
2011-09-07 09:05:29 - Re: PROTEST VINEYARD RACE
@ Aaron

To put this on the knife edge (0.05nm <> 1 meter). What about the width of the boat when it rounds the mark. 125 cat has a width that would indicate that it is not sailing around the marker under these conditions. Most of the boats is wider than 0.05nm, as far as I know. In reality, we sail with knife edges and can give a damn about the width of the boat.
Posted by
AGage


Users avatar

Posts
411
Registered at
2008-12-27 10:31:57
2011-09-08 12:27:24 - Re: PROTEST VINEYARD RACE
I think you have misunderstood.
At max Zoom, 100 pixels = 0.05nm (at least), so:
1 pixel is approx 1m at that scale (the scale indicator is 100px wide) - and different latitudes will have slightly different scales, so often 1 pixel will be > 1m

But again, to the server, your boat is just a point on the globe? It knows nothing of boat size.
So our boats are a moving point, rounding a point (mark).
I help develop the client interface for the best online ocean racing sim there is... __/)/)_/)__
Posted by
AGage


Users avatar

Posts
411
Registered at
2008-12-27 10:31:57
2011-09-08 12:31:34 - Re: PROTEST VINEYARD RACE
NOR Jawik said @ 2011-09-07 09:05:29:
Most of the boats is wider than 0.05nm, as far as I know.
=====================
0.05nm is about 95m...
So they are much less wide than that

--- Last Edited by Aaron Gage at 2011-09-08 12:32:05 ---
I help develop the client interface for the best online ocean racing sim there is... __/)/)_/)__
Posted by
Spindrift


Users avatar

Posts
20
Registered at
2008-10-09 08:54:53
2011-09-08 15:24:58 - Re: PROTEST VINEYARD RACE
"So our boats are a moving point, rounding a point (mark). "
taking the geometry example above and other mathematical axioms and postulates you could redefine the reference field so the mark point was moving around the boat point and the boat point was stationary. In which case a protest could not be upheld for hitting or passing over the mark, as it would have hit or passed under you.


--- Last Edited by Spindrift X5 at 2011-09-08 15:26:31 ---

Page: 1 2 Next

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

Valparaiso to San Francisco 2025

Get ready for an exhilarating new challenge as we set sail on the fourth leg of the 2025 Ocean Championship Series! Following in the 19th century footsteps of Isabel Allende's heroine, Eliza Sommers, 'Daughter of Fortune', this all-new route takes us across the vast eastern Pacific, from Valparaíso, Chile, to San Francisco, California - a 3500nm journey of endurance, strategy, and pure sailing adrenaline. This leg will be raced aboard the powerful Rapido 60, pushing sailors to their limits as they navigate the open ocean. Do you have what it takes to conquer the Pacific? Join us and put your skills to the ultimate test!
PRIZE: SMPF
Race #1900
INFO by brainaid.de
Rapido 60 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ2 - OCCH - SUPSOL - SYC
Race starts: Apr 07th 11:00 Registration Open!
▶ Flash
GO TO RACE

Red Eye - Round White Island 2025

We remain in New Zealand for our second “Red Eye Special” and another IRL Kiwi classic - the Round White Island! IRL still “currently on hiatus” following the island’s eruption of 2019, this race was last raced on SOL in 2020. It’s about 300nm there - out the Hauraki Gulf and south down to the island in the Bay of Plenty - and back to Auckland. This year we’ll be racing in our ever-popular take on the TP-52. Hau tika!
Race #1844
INFOby brainaid.de
TP-52 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC - RED
Race starts: Apr 06th 12:00 Registration Open!
▶ Flash
GO TO RACE

Moheli PYOC 2025


For our first sprint of Q2, we will re-visit the African archipelago nation, L’Union des Comoros, and its most southern island, Moheli, in the Mozambique Channel. Created by MustangMark in 2014 this is a “Pick Your Own Course” round the island, approximately 20nm in our First 27. Expect winds to be light and variable; we are in the Tropics.
Race 1907
INFO by brainaid.de
First 27 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
SPRQ2 - SPRCH - SUPSOL – SYC
Race starts: Apr 05th 09:00 Registration Open!
▶ Flash
GO TO RACE

Africa by Sea - Tangier to Abidjan


Whatever about pharaoh Necho II’s Phoenician expedition of the 7th C BCE, the Carthaginian Hanno the Navigator with more certainty sailed south from Tangier to explore the West African coast two centuries later, but how far he got is a matter of more conjecture. However, if he did the 2300nm to today’s Ivory Coast he would have found little there other than good shelter in the vast lagoons behind the dunes, much the same as today, excepting the highly industrialized port of Abidjan. Not a great haven for a stop-over but let’s take the 90ft Monohull anyway.
Race #1855
INFOby brainaid.de
90ft Monohull PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC - ABC
Race starts: Mar 26th 17:00 Registration Closed
▶ Flash
GO TO RACE

Sea Lion TIMED Race 2025

Come on down South for long days of sunlight and strong bracing winds to race our Finngulf 43 as many times as you like - 117nm as the albatross flies - through some of the islands of the Falklands archipelago. This is a TIMED race, so you may RE-REGISTER HERE to try again, after finishing a run. You will have 13 days and 11 hours to test your skill and decision making after the race opens.
Race #1903
INFO by brainaid.de
Finngulf 43 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ1 - TRCH - SUPSOL - SYC
RACE CLOSE: Saturday,
05 April at 23:00 UTC
Race starts: Mar 23rd 12:00 Registration Open!
▶ Flash
GO TO RACE

Melbourne Osaka Cup Double-Handed Yacht Race 2025

Welcome once again to what these days is Sailonline’s almost annual virtual Melbourne to Osaka Yacht Race. In real life, this double-handed 5500 nm race between these two sister cities, one deep in the southern hemisphere, the other high in the northern hemisphere, is run every four to five years, and this year is such a year. So, this year’s online version is in sync with the Melbourne Osaka Cup 2025 organised by the Ocean Racing Club of Victoria (ORCV), and the Sandringham (SYC) and Osaka Hokko (OHYC) yacht clubs. We’ll be racing the well-known First 40, a popular size of boat which should be a good match for many of the boats entered in the real race. With the doldrums unavoidably lying across our course, you can expect to be at virtual sea for at least a month!
Race #1669
INFO by brainaid.de
First 40 Particulars
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC
Race starts: Mar 16th 06:00 Registration Closed

▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member Patrick70119
  2. Sailonline Yacht Club Member WRmirekd
  3. Sailonline Yacht Club Member CriticalHippo
  4. Sailonline Yacht Club Member vida
  5. Sailonline Yacht Club Member KaSToR
  6. Sailonline Yacht Club Member rafa
  7. Sailonline Yacht Club Member FreyjaUSA
  8. Sailonline Yacht Club Member Kipper1258
  9. Sailonline Yacht Club Member bonknhoot
  10. Sailonline Yacht Club Member rumskib

View full list

Series

Mobile Client

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

The mobile client