Acceleration GA

CronoDroid · Post by **CronoDroid** » Thu Jan 29, 2009 1:49 am

Naboki, I think the laws of physics went out the window as soon as "space drag" and "guns making noises in space" started coming into play.

Compellor · Post by **Compellor** » Thu Jan 29, 2009 2:55 am

Heh, didn't see the above post. I agree with Crono, more or less.

Sealer · Post by **Sealer** » Thu Jan 29, 2009 5:21 am

Just do something so it's not useless 80% of the time

Compellor · Post by **Compellor** » Thu Jan 29, 2009 7:08 am

Well, after nearly two weeks, it looks like a majority (63%) agrees that something should be done, there just isn't a lot of agreement as to what. The booster upgrade idea wasn't part of the original poll, but I'm not sure I like it anyway. It's nice to know it's possible, though. Support for increasing cruise speed is vocal, but not numerous. Moving the GA to Tac is more popular, but not overwhelmingly so. I'd propose a runoff poll, but this in the hands of CC staff regardless. So far the only member to chime in is Weedman, who supports doing nothing.

Those of you who want a code fix are welcome to learn C++.

Naboki · Post by **Naboki** » Thu Jan 29, 2009 10:10 am

CronoDroid wrote:QUOTE (CronoDroid @ Jan 29 2009, 02:49 AM) Naboki, I think the laws of physics went out the window as soon as "space drag" and "guns making noises in space" started coming into play.

Maybe the alleg universum consist of an interfuseing aether, that would solve the problem with noise and space dreg, and would save my argument too

finki · Post by **finki** » Thu Jan 29, 2009 3:46 pm

Naboki wrote:QUOTE (Naboki @ Jan 29 2009, 11:10 AM) Maybe the alleg universum consist of an interfuseing aether, that would solve the problem with noise and space dreg, and would save my argument too

You mean terrorists destroyed a gigantic truck loaded with beer which now fills the universe?
That would also explain the need to consistently fight for more territory in "Ale Giants" or how it was called.

Compellor · Post by **Compellor** » Thu Jan 29, 2009 6:21 pm

The ships have infinite fuel for cruise speed, but that's not unreasonable because they could simply be carrying enough fuel for an hour, or even less, and that's not worth modeling by the game engine. The change in mass of the ship as fuel is depleted might have been worthwhile, but they decided to make ammo and booster fuel massless too, for gameplay reasons.

If you increase the thrust of a rocket in atmosphere, and keep the mass the same, its top speed is going to increase unless its hull form changes to increase drag. That would probably negate the acceleration increase as well, but I'm not a rocket scientist. Anyway, yes, increasing thrust will lead to increased fuel consumption unless efficiency (specific impulse) is also increased, but we've already established that cruise fuel is arbitrarily sufficient. The accel GA does not at present increase booster thrust, and if it did it would also increase fuel consumption, which is a multiplier of thrust. So why doesn't the accel GA also increase cruise speed? One might suppose that maximum thrust is only applied when not at or above some arbitrary cruising speed, but that doesn't explain the booster issue. In reality, the game engine simply makes drag proportional to ship thrust, so that drag and thrust are equal at the cruising speed. There are only two real-world explanations I can conceive of for this:
1) Alleg takes place in a fluid, and improved thrust is achieved by adding an outboard motor.
2) Alleg takes place in vacuum, and "drag" is a euphemism for the ship's rear thrusters (Juckto's suggestion)
The second explanation doesn't make much sense, because no ship's retro thrusters are capable of equaling the ship's thrust plus the booster thrust. Most ship's retro thrusters can't even match the ship's thrust. The first explanation doesn't work very well either, because drag should be proportional to airspeed, so there's no reason for a scout to suddenly decrease its drag by a quarter when you're trying to slow down.

Of course the above assumes that we are talking about rockets. If this is a jet engine in a fluid (such as Earth's atmosphere), things get more complicated, though I don't think it changes the overall problem.

guitarism · Post by **guitarism** » Thu Jan 29, 2009 6:59 pm

Or your just severely overanalyzing this, and it's a game, and the physics we have are for gameplay reasons. What a thought!

Leave the accel Ga where it is.

Clay_Pigeon · Post by **Clay_Pigeon** » Thu Jan 29, 2009 7:15 pm

I caution you against using several variations of the same piece of equipment. EoR did something similar, and while it worked on the surface, it made all but the *most* routine cargo loading a gigantic pain.

A very easy code-based manipulation (and I can't believe I just thought of this) is to have the ship accel ga perk max booster thrust as well as ship max thrust. As a result, the ga would have no impact on booster top speed, and this would probably be a less invasive change than rewriting the physics engine

Compellor · Post by **Compellor** » Thu Jan 29, 2009 10:00 pm

CP: Is it really so easy to do? I don't think anyone who's actually on the dev team has participated in these two threads.

I'm not a coder, but I've skimmed the code. The accel GA interacts with ship thrust in shipIGC.cpp:

Code: Select all

float                MyHullType::GetThrust(void) const
{
    return m_pHullData->thrust * m_pship->GetSide()->GetGlobalAttributeSet().GetAttribute(c_gaThrust);
}

though I can't be sure it doesn't interact elsewhere.

I suppose you'd need to transplant "* m_pship->GetSide()->GetGlobalAttributeSet().GetAttribute(c_gaThrust)" to at least one point in afterburnerIGC, and maybe elsewhere. Then there's the bug testing, of course.

The trouble with changing the code is that releases don't happen at all often, this change might not even make it into the next release, and this change wouldn't be core-specific - it'd force all cores to adopt something which a vocal minority view as a change rather than a fix. Regardless, if you want the code changed, there's a forum for that. This is the thread to determine whether something should be done for cc_04, and the result so far has been an emphatic maybe.

Also, because I'm feel like being a jerk today:

Clay_Pigeon wrote:QUOTE (Clay_Pigeon @ Jan 29 2009, 02:15 PM) A very easy code-based manipulation (and I can't believe I just thought of this) is to have the ship accel ga perk max booster thrust as well as ship max thrust.

Compellor wrote:QUOTE (Compellor @ Jan 7 2009, 11:09 PM) The best way to fix this, I think, would be to make accel GA also apply to boosters.

I can't believe it either, CP. Anyway, like I said in that thread, doing that would be a nerf to Giga and a perk to TF, be cause they have faction accel GAs. I'm not saying that's a bad thing, or can't be worked around, just something to keep in mind.

I'm not thoroughly familiar with EoR, but I've looked at the core, and what they did with boosters seems substantially different from what I did. Regardless, it does seem a bit rough around the edges, which is why I'm not promoting my booster core.