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Re: Vector Movement

From: Oerjan Ohlson <oerjan.ohlson@t...>
Date: Wed, 03 Sep 2003 14:03:52 +0200
Subject: Re: Vector Movement

Sorry about the lack of reply markers in the previous post; I have no
idea 
what happened. Since the absence of those reply markers make it rather 
difficult to follow who said what when, here's a corrected version It 
should've looked like this:

Jared Hilal wrote:

>>>1) At the risk of picking nits; the problem is not rotate-burn-fire,
but 
>>>rather rotate-burn-ROTATE-fire.
>>
>>This is the *esthetic* problem Jared has with the current Vector
rules. 
>>Unfortunately neither it isn't the *game balance* problem he intended
his 
>>proposal to solve
>
>Actually, this is the root cause of the problems (symptoms) that I am 
>trying to solve,

No, it isn't - at least not if the problems you're trying to solve are
the 
game balance problems of Advanced drives and wide-arc weapons being
badly 
overpriced in Vector, and that's what you said they were... I already 
explained this in the post you replied to further down in this post, but

here it is again in a shorter form:

Manoeuvre in Full Thrust is only really important in that it allows your

ships to (or prevents them from) getting into positions where they can
fire 
their weapons at the enemy, and/or into positions where the enemy ships 
can't return fire effectively.

In Cinematic, with its quite limited abilities for ships to change
facing, 
wide-arc weapons are easier to point towards the enemy (and thus more 
valuable) since you don't need to change course as much to do so as you 
would if you used narrow-arc weapons. Similarly Advanced drives improve 
your ability to change facing, thus giving you advantages similar
(though 
not identical) to those you get from wide-arc weapons.

FB Vector allows *any* ship can rotate to bring its narrow-arc weapons
to 
bear on the enemy, due to its any-angle rotations. The *number* of 
rotations in Vector matters very little, if at all, to the relative 
worthlessness of Advanced engines and wide fire arcs in Vector; the 
important difference is that in Vector a thrust-2 ship can turn 180
degrees 
in a single turn while in Cinematic that same ship could only turn 30 
degrees per turn.

It is the *angle* a ship can rotate which is by far the most important 
factor, since that is what determines whether or not you can bring your 
weapons to bear against the enemy, not the *number* of rotations it can 
make. As long as you allow any ship is able to rotate the full 180
degrees 
in a single turn no matter what its thrust rating is you'll have these
game 
balance problems with wide-arc weapons and Advanced drives being
overpriced.

>Anyways, for ships with low thrust (which happen to be the larger
ships), 
>this means that the single-side thrusters are often close to half as 
>powerful as the main drive.  Huh?

All of the single-side thrusters taken together are close to half as 
powerful as the main drive on its own, yes. Is there a problem? (BTW, 
towards the end of this post you're actually - though accidentally - 
arguing that the FB1 background blurb describes precisely this kind of 
powerful single-side thrusters :-/ )

>>Unfortunately for your suggestion, you haven't correctly identified
the 
>>problem. (Unfortunately for GZG, neither did we playtesters during the

>>FB1 and FB2 development :-/ )
>Then what is the root cause of the problem?

I explained this in detail in the post you're replying to. Since you 
replied to it, I do hope that you read it as well.

>>What your suggestion does is to prevent the narrow-arc ships from
keeping 
>>the enemy under continuous fire (ie. shooting at him every turn)
*while 
>>accelerating away from him*. Trouble is, this is merely a special case
of 
>>the real problem - and removing this special case while leaving the
real 
>>problem unsolved won't make wide-arc weapons any more useful.
>>
>>The real problem is that the narrow-arc ships can keep the enemy under

>>continuous fire *at all*, as opposed to Cinematic where narrow-arc
ships 
>>tend to make an attack run and then spend several turns during which
they 
>>can't fire on lining up for their next attack run (or else come to a
full 
>>stop, in which case they can rotate freely but make themselves very
easy 
>>missile targets and also allow the enemy to control the range).
>
>But in vector, narrow arc standard drive ships should be able to keep
the 
>enemy under continuous fire if they forego accelerating in any
direction 
>except towards the enemy.

 From an *aesthetics* point of view I don't disagree with your "should".
I 
thought so too both five and three years ago; that's why I pushed so
hard - 
and, unfortunately, successfully - for allowing ships to rotate through
any 
angle for a single thrust point in the FB1 and FB2 movement systems.
(Funny 
though; you're the very one who listed a number of examples where 
vector-moving ships in a certain TV show did *not* rotate to keep their 
narrow-arc weapons trained on the target continuously in spite of not 
attempting to get anywhere in particular ;-) )

It's just that these any-angle rotations are precisely the root cause to

the *game balance* problem: they are the very reason why wide-angle
weapons 
and Advanced engines are badly overpriced by the FB ship design system
if 
you play Vector.

If you want to solve these two game balance problems you only have two 
options: either devise a completely different set of ship design rules
for 
Vector movement (ie. lower the price of wide-arc weapons and Advanced 
drives to match their value in Vector), or restrict the angle a ship can

rotate in a single turn (ie. increase the value of  wide-arc weapons and

Advanced drives to match their price).

(Of course there's a third option, namely to ignore the game balance and

the ship design rules entirely, but since that doesn't actually *solve*
the 
problems and it wasn't what you said that your proposal was intended to
do 
I'm leaving that option out for now.)

>This, combined with your "while accelerating away from him" results in
the 
>majority of cases, rather than the "special case", as you said.

 From an aesthetics point of view, sure. But according to your previous 
post your proposal was intended to solve the *game balance* problem
(namely 
that wide-arc weapons and Advanced drives being overpriced in Vector),
and 
from the game balance point of view you're completely wrong.

>Accelerating toward the enemy and then rotating (once) to keep him
under 
>fire is reasonable to me.

Reasonable or not, it won't help making those wide-arc weapons and
Advanced 
drives worth their cost in Vector. You're confusing aesthetics with game

balance.

>>The reason why wide-arc weapons cost more than narrow-arc weapons is
that 
>>the wide-arc weapons *in Cinematic* have a much better chance of
having a 
>>target in arc and thus on average get to fire more shots each over the

>>course of a (Cinematic) battle than narrow-arc weapons do. Fewer
weapons 
>>firing more shots each per battle give about the same damage-dealing 
>>capability as more numerous weapons firing fewer shots each, so for a 
>>given amount of points you get fewer wide-arc weapons than you
could've 
>>gotten narrow-arc weapons of the same type and class
>And the same should be true for vector,

It *should* be true for vector, yes. On that we both agree. So why do
you 
propose something which doesn't allow it to *be* true in Vector?

>>(Kra'Vak pay the extra points for better engines instead of for extra 
>>fire arcs, but the end result is the same: they get fewer guns which
get 
>>to fire more shots each than the same points value of single-arc human

>>weapons on human-engined ships.)
>>
>>However, if 1 thrust point in Vector is sufficient to rotate the ship
to 
>>any facing it likes - and in the FB Vector rules it is - then you can 
>>almost always rotate the ship to point your single-arc guns at where
the 
>>target will be after movement.
>
>However, on the turn after you have pointed your ship at the target,
you 
>should have to make a choice between keeping the target in the
engagement 
>basket or continuing your acceleration, rather than being able to do
both.

If you want to continue the battle, keeping the target in your
engagement 
envelope is FAR more important than continuing your accelleration.

[...]

>But, if the player (ship captain) had to chose between pointing at the 
>target and turning to accelerate in a direction 60 degrees or more from

>the target, then the ability to, for example, travel course 12 with a 
>target at bearing 3, face heading 5 to both decelerate and converge on
the 
>target (bearing 3) and still be able to fire at that target with
batteries 
>that bear into your port broadside is worth the additional points and
mass.

This seems to be where you go wrong: you assume that being able to 
accelerate away is as important as being able to fire your weapons, but
it 
isn't. Being able to fire your weapons is far, *far* more important, so
the 
"choice" you're talking about is trivial.

If the player has to choose between pointing *two* wide-arc weapon 
batteries at the target while accelerating away, or point *three* 
single-arc weapon batteries of the same type at the target and not 
accelerating away, the three batteries almost invariably beat the two.
No 
matter which armament you choose, if you play Vector the armament it
will 
almost certainly point at the enemy throughout the battle - so the 
single-arc ship effectively has 50% more firepower than the wide-arced
one 
*throughout the battle*.

In Cinematic the choice is quite different: due to the much lower
turning 
ability ships have in Cinematic, you get the choice between on one hand 
three single-arc weapons which probably *won't* point at the enemy most
of 
the time, and on the other, and on the other two wide-arc weapons which 
will probably *will* point at the enemy most of the time. Here it isn't
a 
matter of slowing down the enemy's rate of closing; instead the question
is 
whether or not your weapons will get to fire *at all*, and the 50% extra

firepower the single-arc weapons get on the few occasions they do manage
to 
fire is just about enough to even the odds against the more numerous
shots 
the wide-arc weapons fire during the battle.

[...]

>The problem is not that the single rotation can acquire the target once
, 
>or even continuously,

Then could you please explain why complaints about wide-arc being 
overpriced in Vector weapons appeared about three months after *FB1* was

published, and have continued ever since? FB1 Vector only allows a
single 
rotation per turn, so according to you it should've been free of this 
particular game balance problem?

>If the ship coasts while pointed at the target, then he has given up
the 
>maneuver initiative in favor of an attempt at overwhelming (with his 
>maximum firepower) the target before the target can redefine the
maneuver 
>situation, while the opposite is then also true (giving up firepower in

>order to maneuver).

You forget that manoeuvres in Vector are far more limited than they are
in 
Cinematic. In Cinematic giving the manoeuvre advantage up often means
that 
you don't get to use your higher firepower to full effect; but in Vector

the target can't re-define the manoeuvre situation much anyway so giving
up 
a small advantage in manoeuvrability to gain a massive advantage in 
firepower is usually not a very hard choice to make.

>Actually, I think the FB1 rules work well,

Since they have exactly the same game balance problems wrt. wide-arc 
weapons as the FB2 ones have, I don't think they work well.

><snip	catastrophic failure discussion>
>>(FWIW quite a few of the larger ships destroyed in B5, particularly in

>>the Narn-Centauri conflict, blow up as a result of secondary
explosions 
>>rather than as an immediate effect of the incoming fire. The only way 
>>this can happen in FT is if the Power Core fails catastrophically.)
>
>Unless you consider rerolls to represent those secondary explosions. :)

I don't. If a ship is destroyed by re-rolls it can't fire any more 
afterwards, but at least two of those B5 ships (Centauri battlecruisers)

kept firing for a while after the enemy had stopped shooting (in one
case 
due to starting to explode itself, in the other because the Narn ship
had 
entered the jump gate).

><snip more game turn length discussion>
>
> >From FB1, pg. 3, right hand column, "Rotation" section, 1st para.:
>"...(the only difference between rotating 30 degrees and rotating 180 
>degrees is simply that, once the thrusters have started the ship
spinning, 
>the ship is allowed to rotate for [a] longer [period of time] before
the 
>thrusters burn again to cancel the spin)..."
>
>So, IIUC, FT thrusters are probably more than 1/4 g, probably closer to
1 
>g, but only on for a brief burst, then 0 g coast, then short ~ 1 g 
>counter-burn.

If they're that powerful (close to 1 g), then they're also powerful
enough 
to push the ship sideways at a fairly considerable acceleration :-/
You're 
the one arguing against such powerful lateral thrusters, not me.

>Further, if I understand the assumptions behind your math, you are 
>assuming MD1 ~ 1g over a full game turn, but if you rotate twice,
taking 
>1/2 of the game turn (total of 2x Rotate), then MD1 ~ 2g because the
time 
>that the drive is on is much less.

Not exactly. *Manoeuvre thrusters* need to be able to make ~2g burns or 
more in order to push a ship sideways or backwards during a turn in
which 
the ship rotates once or twice (which means that the ship is able to
rotate 
even faster - isn't that nice? <G>). *MD1* (Main Drive 1) doesn't
however, 
since a ship capable of both rotating twice and making an MD burn in a 
single turn must have at least MD3 (each rotation uses up 1 thrust
point) 
so you can safely assume that its "MD1" burn represents a shorter burn
at a 
higher thrust level.

(This is why FB2 Vector rotations use up thrust points from the MD pool,

BTW. Of course this assumption screws up the nice "true Newtonian Vector

Movement" concepts you and others have discussed recently, but that's 
another discussion :-/)

>>When even huge ships like an Omega or a Shiva could potentially rotate

>>this fast, even the fastest "GZGverse scale" with its 100-second game 
>>turns clearly allows a ship to make two 180-degree facing changes in a

>>single turn and still leave time for a main drive burn and/or firing 
>>weapons :-7
>
>But I would not want to be in a DCP, or a SBA, or etc. (and therefor
not 
>strapped into a shock couch) when the ship makes a 1g rotate burn, 0g 
>coast, 1g counter-burn, (total 30 sec) 2-4 g MD burn (40 sec) (could be
as 
>high as 8-12g on a destroyer or corvette), 1g rotate burn, 0g coast,
and 
>1g counter-burn (another 30 sec), all in a 100s game turn.

Sure. This is exactly why the GZGverse canon claims that gravitic 
compensators provide such a powerful combat advantage... and why most
other 
SF backgrounds featuring space combat have similar devices too :-/

Regards,

Oerjan
oerjan.ohlson@telia.com

"Life is like a sewer.
  What you get out of it, depends on what you put into it."
-Hen3ry

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