Collisions - stopping dead in the water

[euphoria]

When colliding, the boat with ROW should never be slowed down.

Any suggestions on how the boats should appear after a collision? The can't be bumbed away from each other, as they might land on top of other boats near by.

Is it a good solution to enter ghost mode the second two boats hit, to make it possible for them to seperate without hitting again and not loosing speed? They should not appear as ghost to other boats. The ghost mode could be active until they have seperated or for a fixed time period.

I'm not supporting Jens' suggestion on having an exclusion zone. I think it will be too complicated to have one that works well due to lag. More on that when (if) Jens makes a topic on that suggestion.

[Guest]

This gohst baot thing appears like a good idea. It does however bring in more complexity again. Me too, I am against that exclusion zone. :alarm: As already pointed out, the better the skippers know the rules, (and apply that knowledge) the better the races will be anyhow! :v-wink: Too wishful thinking? :rolleyes: I don't know.

[No Match]

I'm working at the moment on the exclusion zone thing.
Though I have now chosen to call it penalty Zone instead.
It's basically speaking a cone shaped area widest at the front and narrowest at the back, with the boat in the middle. If the hull of another boat with ROW enter the zone, the programme start tracking the courses of the boats involved, calculating the predicted meeting point along the way. If calculated meeting points = collision, then penalties are given at the moment
1) The ROW boat tacks.
2) Pass behind the stern of the offender, after having fallen off.
3) The offender tacks on top of a ROW boat that have made the move of falling off to pass behind first.
Those are only the basic principles though.

[No Match]

Your ghost mode suggestion have put me on a better idea Harald, of using simple vector projection mathematcis and calculations based on pythagorean triangulations instead of the admittedly rather complicated calculations of areals.
As this are all rather simple calculations, I don't think it would slow down the program to any noticeable degree.

[Redtail]

Collisions should be modeled with some sort of physics. Starboard or not, if you T bone a boat, you're going to stop. If you ram from behind, depending on relative speeds, and lateral movement, you will lose some of your speed. Certainly, to a greater or lesser extent the wind flow in your sails will be disturbed, with an effect on your speed and pointing.

MS flight sim models flight dynamics very well. The physics of sailing is no more complicated than that of , say, glider flight. If the aircraft in FS2k were modeled as the boats we sail in are, they would be laughed out of the community. I'd forgo all of the improvements (except lag reduction) for realistic physics.

[euphoria]

That's more or less how it works now. That's a problem in this game because the offending boat will still be ahead after doing it's 360. Maybe extending penalty to 720 will make a big difference?

When colliding side to side when luffing, boats shouldn't be slowed down at all. That would help alot! Rule 16 has to be modeled better in this game, otherwise (some) people would sail the game as it was a bumpy car game.

I used to play VirtualCup. They added a nice feature: If a collision happened (on your computer) it checked if the opponent also experienced a collision. If he did, a penalty was given and boat physics appeard as if they had hit. If opponent PC responded negative, you got the message "opponent didn't whitness a collision" on your screen, and boats sailed on as if nothing had happened. This could be used in this game as well! If you hit the stern of the opponent, he might have been clear on his screen. In this case, you should be able to sail through his stern as in ghost mode.

[No Match]

Let the penalties for an infringement in VSK be the same as it would be on real water's according to the ISAF rules. That I think would entail introducing 720's to the game.
With basis on a standard minimum distance before collisions are inevitable - measured from ROW boats stem to unfavoured boats centerline - you could still make the program hand out penalties to infringing boats without collisions.
Lets say that this minimum distance from ROW boats stem to infringing boats centerline = AB then you add a certain fixed extention to the AB value f.ex BC = 1/4 AB to compensate for the distance from centerline to beam. On top of that you add a another fixed extention to AB f.eks. CD = 3/4 AD to give the ROW skipper time to think and room to take avoidance action.
If a ROW skipper under such conditions takes action and falls off to pass behind an infringing boat, or tack to avoid collision, inside the AD distance, the other culprit will not get away with it.
The basic AB distance in the above mentioned equation could be calculated through a simple comparision of the underlying matrix positonal values of each involved boat.
The difficult thing about this is the fact that the critical distance AB between two boats on collision course generaly decrease sharply towards the ends of the hull of an involved boat, and besides vary somewhat with the angle of approach of each boat in a collision course situation.
I haven't had anything to do with vector mathematics since I left high school so far back I can't recall, so this is something of an awakening for me:glasses:.

[essie]

Additionally one could add another variable "i" to the formula, taking into consideration the ROW boats relative "impact location" (if avoidance actions were not taken) - say a factor of 1 forward of the non-ROW boats mast and decreasing to .1 at the stern. This algorithm would help the program to differentiate between a close near miss and an obvious barge, ignoring the ROW rules. An infringing boat with an infraction value above a critical iAD value, in addition to getting a 360 could also get a speed decrease (as happens after collisions now in VSK). Extra punishment for gross rule violations.

To avoid this in team races between boats of the same team, a ROW boat wanting a non-ROW team mate to pass would simply hit the tab key thereby losing rights as when doing a 360.

[No Match]

PROPOSAL ON THE BASIC PRINCIPLES OF A STAND OFF TRIGGERED PENALTY JUDGEMENT ROUTINE FOR VSK-2 (As supplement to the existing touch triggered penalty judgement routine).

BASIC UNDERLYING ELEMENTS.

1) All measurement calculations to be made by use of simple vector geometrical formulas.

2) Basic measuring of the distances involved to be made from a ROW boats stem to a disfavoured boats central
longitudal axis. Compensation for distance from central longitudal axis to beam should be made with a simple
ad on to the basic ROW boat stem to disfavoured boat from central longitudal axis distance. This contributes
to limit the amount of distance control elements the programme has to handle during a race.

3) Any potential collisions are to be predicted on the basis of where a ROW boats stem will cross the central
longitudal axis of a disfavoured boat and vice versa. This also makes for simplified object tracking routines
(and therefore hopefully less lag).

4) In the calculation of necessary stand off distances between boats for avoidance of collisions, one should
operate with two types off basic stand off distance elements. Namely a critical distance - under which a ROW
boat cannot by itself alone avoid collision with an infringing disfavoured boat by falling off from the direction
of the wind – and a prudent distance of a certain specified length as an extension to the critical distance – in
order to give the skipper of a ROW boat time to think through his options and some room to manoeuvre and
shout for his or her rights.
The Calculation of the critical distance is to be based upon the turning radius of the involved boat type, as
measured from the stem of the row boat.
If a ROW boat tacks in front of a disfavoured boat or fall off to pas behind a disfavoured boat, with its bow
inside the outer limit of the prudent distance, then the infringing disfavoured boat should automatically qualify
for a penalty.
The prudent distance should be much smaller in collision course situations with boats on the same tack, than
for collision course situations with boats on opposite tacks, on account of the lesser closing speeds involved in
situations where boats are on a collision course while on the same tack.

5) The handing out of penalties should be semi automatic in fleet mode, in that the skipper of the offended ROW
boat have to approve or decline the pen to the programme by hitting certain predefined keys within a certain
time limit for the protest to take effect.
This is a feature that is a must as regards team racing, in situations where you don’t want to give a pen to a
team mate when/if you chose to pas behind him/her.
In pure match racing mode the penalties should be handed out automatically, as a reflection of the generally
more vigilant attitude of judges during match races on real waters, as compared with the performance of
judges during fleet races on real waters.

More to follow soon through the mailing list in PDF format (are currently working on the basic trigonometrics of my proposal).

(Edited by No Match at 8:01 pm on Jan. 22, 2001)

[admiral 1]

No matter how fancy the rule implication, without cyncronisation it will do nothing to imrove fairness.

Il'd like to be able to track data traffic during a race. Does anybody have any idea? Is there a tool for windows that will run parallel, without influencing the traffic?

BTW in real live sailing a boat gets damaged, might get sunk when t-boned. So except for some scratches on the side, skippers just might have to stay clear. And in the end appear in front of the committee

[No Match]

I've just managed to collect myself enough :zzz: to send off my basic Ideas, on a stystem for penalty handouts triggered by a ROW boat within a certain distance from an opponent, to [email]vsk2@dunet.com.[/email]
It's mostly simple trigonometrics with old Pythagoras and some cos and sin calculations aside. Though as I haven't worked to any serious degree with math since my gymnasium days, it wouldn't surprise me if some of the formulas I use are a bit off the mark:confused:.
I anyone of you are interested please put in a reply on this topic or mail me directly, and I'll send it to you individually. That would probably be better than filling up Murray's mailbox with my crap through using the mailing list :rolleyes:.
As my proposal contains graphics it will come as an attachement of 8 files in either compressed TIFF (group 4) or JPG format.

(Edited by No Match at 8:04 pm on Feb. 22, 2001)


(Edited by No Match at 8:05 pm on Feb. 22, 2001)

[admiral 1]

Hi Jens,

send me the stuff.

Tx in advance.

Theo

[No Match]

As for response from the VSK-2 development team - be free to :walkingsm: over to my last posting under Kamikaze.