Post by iconPost by zezo | 2017-11-02 | 12:33:27

I'm moving the post below to its separate thread, so it won't get lost in the noise.

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Post by iconPost by bonknhoot | 2017-10-31 | 20:27:13
I was a pretty serious VR 0$ racer for a couple of years in the days of straight wind in boxes and massive shifts every 12 hours. It wasn't realistic, but it was quite good nonetheless. You did have to understand VMG and VMC and polar diagrams. Excepting the very long distance races, you didn't really need to use a router either. I was glad to read in this blog that this game is still alive in the form of regattagame.net.

I bought some credits every now and then to see how I would do against the top of the fleet. I hung in there, but, yes, those guys are good. Having had a balance of credits sitting on the site after I moved on to IMO better things (SOL, sailonline.org), I tried my hand again two years ago for the Clipper Race. I now found it hard to enjoy this sailing towards the big 12 hour shift, and really wondered what the point was of having the wind varying smoothly across position but not at all across time. I gave up leaving a few credits sitting in my account. With all these recent changes I am reading about, I must go and have a look have I still got them!

I gather from this lengthy thread that a wave of dissatisfaction is rolling over VR. It is not for the first time. I noted a very early remark by zezo that really it wasn't a great solution to build your own game, as there were already several out there: sailonline, Virtual Loup de Mer, LiveSkipper are the best known. They are small communities and once you've joined one you're unlikely to want to try another. Although they are all basically the same, they are each complicated and not-real in different ways. Thus they can all be improved, but since the games are run as clubs not profit centres, improvements happen slowly. Plenty of talk, not that much action. But if one or other of these clubs got bigger, improvements might speed up.

So, my general advice is join another game and get involved, and my biased advice is join sailonline.org.

I genuinely think SOL probably has the best racing engine. I say probably because I am not so very familiar with the other two mentioned earlier in the same breadth. Let me go through it.

WIND
SOL is usually fed with 7 day NOAA gribs. Usually these gribs contain data on 0.5 x 0.5 degree grids, sometimes for the very longest races this is zoomed out to 1 x 1, but more times it is zoomed in further to 0.25 x 0.25 when we use NAM-Awip, or to 0.05 x 0.05 when we use special hires gribs that model in the local coastal and thermal effects on top of the NOAA synoptics. The NOAA gribs hold discrete data at 3 hour intervals forward, our hires gribs at just 1 hour intervals.
By applying bilinear interpolation across position, and shape function interpolation across time, to these gribs, in the game the wind varies CONTINUOUSLY across the chart and across time. The interpolation used is the mathematically most rigorous; the u component (up/down) and v component (east/west) are interpolated separately, then vector-added. This tends towards less wind when there are big changes in direction from one data point to the next. The Doldrums are tricky on SOL.
New forecasts blend into the game every six hours. The change is gradual and smoothed and the change is announced by the sound of wind and a message. There is a time-bar at the bottom of the screen. Just pull the bar forward and you will see the wind arrows (or barbs, if you prefer) and iso-vents change on your screen.

MOVEMENT
Our Engine updates the position of every boat every 10 seconds; this frequency can vary a little, since the server works sequentially, not simultaneously. The position shown on your screen updates every 15 seconds, and if you've sailed the same course for longer than 15 (or is it 20?) minutes, it reduces that display update frequency to every 30 seconds. So, we have almost continuous advancement of boats.

COASTS
Our coastlines are defined by standard GSHHS usually poly-h but sometimes poly-i tiles. If your next advance is going to see you end up inside the defined polygon the server puts you head-to-wind and so you remain, until you do something about it (see STEERING).

POLARS
Our polars are all up on the server, and if you're clever you can write a bit of code to get them from there. Several of our competitors are and two of these - brainaid and Kipper1258 - have made their polar retrieval 'apps' available to the community. These 'apps' are not part of the game in a strict sense, but they are very handy. For example, they also hold the current grib file that the Engine is working with.
The polars themselves contain discrete data per 1 m/s TWS and per 1 deg TWA increment. At each node on the 1 m/s x 1 deg grid there is ONE value for BS, i.e. the best speed the boat can do in that wind from that angle with the RIGHT sail. So, no messing around with selecting the correct sail or remembering to activate AutoSails. It's about the wind strategy, innit?
In between the nodes on the polar grid, bilinear interpolation gives you a continuous 'stufenloser' variation of BS. A fraction higher upwind, a fraction slower; a fraction more wind downwind, a fraction faster; etc, etc.
We have a vast selection of polars that we race, ranging from four-masted tea clippers to floppy-masted DB ice boats, with more normal mono- and multi-hulls in between ranging from less than 20ft to up to 100ft LOA.

STEERING
There is a very simple, intuitive sub-screen to steer your boat from, with a nice polar diagram underneath to give you a guide as to what is fast and what is slow. At its simplest you just enter a COG or a TWA and hit 'set course' and you are now sailing that course or that angle to the wind until you next 'set course'.
However, you can also delay your instruction by entering a value in decimal hours underneath your COG or your TWA and then press 'set course'. You can do as many of these as you like and they accumulate in a list under a separate tab. From there you can edit these Delayed Commands (DCs), in particular change the times they will fire. This is all well-and-good but just a bit cumbersome so those clever clogs brainaid and Kipper1258 have added DC uploaders to their 'apps'. Just type or better copy over (from your router, see later) your DCs to these upload screens and enter the lot in one go.

SEAT-OF-THE-PANTS
It is quite possible to race a good race without using a router and there are three tools to assist you, one built into the game, and two available on external 'apps'. The one built into the game is called the ‘predictor line’. This stretches out for 6 hours showing where you will end up sailing your present course, either on COG or on TWA, or if you like (best setting to select) on both COG and TWA. If you type a delay into the box for that, a yellow dot on the predictor line will show you where you will be, if you set your DC with that delay.
Kipper1258’s ‘app’ which is called AutoGribLoader, because it auto-retrieves gribs, has a graphical DC checker. Type (or copy over) all your planned DCs into his DC uploader area and the DC checker will show you exactly where those DCs will take you. It is very accurate!
Next, we have AGage’s WxInspector, which is nowadays hosted on solfans.org, a blog with interesting if infrequent musings by SOLers for posterity. WxInspector instantly give you the optimum angles you should be sailing in current or entered TWS. It will also plot out isochrones from your current position, both when sailing COG and when sailing TWA; i.e. effectively hundreds of predictor lines radiating out from your position in all directions.
Finally, we have kroppyer’s Spinnacer, which you can download from his sol.kroppyer.nl site, where you will also find other useful stuff including links to Kipper1258 and AGage’s tools. I don’t use it, so I can’t say too much about it. I’m a spreadsheet fiend, myself.
Kipper1258 is an active SOLer, brainaid is a retired SOLer, kroppyer is an inactive (pressure of work) SOLer, and AGage is only with us in spirit these days, but is our Honorary Life Member.

ROUTING
Quite a number of us use routers to plan our course. Some use Expedition and some of those are even ensemble routing, a few still persevere with BlueWater, but most use QtVLM, and with good reason. Despite this router having been designed for the VLM game, its designers have been very helpful in adding features to make it more useful for SOL, in particular they have added SOL interpolation as an option, and a choice of GSHHS tile: poly-I (which was the default), poly-h or poly-i.
If QtVLM has a shortcoming, it is that the shortest time interval it works with is 5 minutes (matches VLM’s needs perfectly), but this shortcoming is significantly reduced by an optimisation process that breaks those 5 minutes down into 1 minute steps.
On the other hand, QtVLM has a function to convert routes into ASCI files containing all and more than the data you need at a time interval of your choice (I usually opt for 3 mins) that with a little repetitive manipulation can be transformed into DCs for checking and uploading. Go to kroppyer for a tool for that.

WAYPOINTS
We do not have a waypoint functionality, but with Kipper1258’s DC-checker being very precise, you don’t really miss it.

PERFORMANCE LOSS
We have performance loss on a change of direction and on a change of tack, followed by recovery. It is not the best feature of our game. High speed boats lose a lot of performance on a change of tack (or gybe) and recover it only slowly, all driven by ‘exit’ BS. However, once you understand it all, there are ways and means for never falling much below 93%. It is only significant in short races at high speeds. When we race our DNs across the ice, we switch off Performance Loss altogether.

RACES AND SERIES
Usually there are at least two races ‘on’ at any given time of the day. The races are split into Ocean, Specials, Sprints and Timed. An Ocean race is an ocean race and a Sprint is a sprint. Specials are everything in between and usually take several days and up to a week, and often copy or buddy some or other IRL (in real life) race. Timed races are done on a course where you can try as many times as you like over 10 days to better yourself. There are quarterly prizes for Ocean, Sprint and Timed, and special prizes for Specials. You only get a prize if you have paid your annual sub of $35, but sub or no sub paid you can race as much as you like, and with no disadvantage versus anyone else.
Post by iconPost by zezo | 2017-10-31 | 20:46:39
Thanks for sharing that information.

Maybe we should move this post to a separate thread because this one has grown too long and serves as kind of open letter to Mr. PG.
Post by iconPost by karriv | 2017-11-01 | 10:09:24
Bonk, thanks for the elaborate post. I too have been racing at SOL, although not actively lately, and can recommend it wholeheartedly.

One thing Bonk forgot to mention is the chat. There's a very active chat in each race, including language specific rooms, and a room for sailtalk only (by that you can probably deduce that the normal chats don't revolve just around sailing;).
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