Suggestion for an improved plague model.
 

EDIT: Disregard this entire post. It doesn't work. There's a better suggested model a few Posts up http://forum.shrapnelgames.com/images/icons/icon7.gif END EDIT

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Original post begins...

OK, I think the current plague model (level 1, 2, 3... plagues countered by level 1, 2, 3 medical abilities) is far too simple. Here's what I'd like to see...

First up, plague damage to population should be in proportion to the population on a planet, not a set figure which applies to any planet.

Secondly, plagues should be able to spread from planet to planet, including to neighbouring allied planets. Planets with space ports should be particularly at risk.

Right, now onto the complex bit:
A plague's severity should be measured as a percentage. 0% means no plague. A small number, for example a 3% severity plague, would be easy to cure, and would cause only a little anger on a planet. It would kill some, but not many of the population, and could probably even be an acceptable long-term status for a planet.
On the other hand, a 90% plague would be catastrophic, and would bring production to a complete halt, threatening to wipe the planet out in a few turns.

The first cool thing about this suggested system is that the plague severity value could change from turn to turn. A planet with a 30% plague might go up to 40% if a combat occurred on the planet, or if another plague bomb was dropped. All sorts of other factors could be worked out to modify the plague severity from turn to turn. Random modifiers (positive and negative) from turn to turn would be a good thing.

Curing a plague would require a ship with a "cure level" higher than the severity of plague. For example, a med bay II might have a cure level of 30, and so be able to completely cure plagues of 30% and below. Simple so far, eh?

Cool thing #2: A ship with cure level 30 can't cure a plague with a severity greater than 30%, but it can "reduce the symptoms". It reduces the plague severity by either its cure level (in this case 30 points), or to a severity slightly above it's own cure level (say, cure level + 10), whichever is the higher.

For example, ship cure level is 30, plague severity is 55%. The ship can't cure the plague, but it can reduce the severity. Reducing it by 30 would bring it down to 25%, which would make it curable. This would be pointless in game terms, so instead it reduces it to 30+10=40. The plague is made less severe, but still can't be cured by a cure level 30 med bay. Geddit?

In the event that two or more medical ships are in attendance, all calculations are based on the highest-rated ship, with a +10% of level modifer for each additional med ship in the sector. Confused? Example:

Say you had a cure level 70 ship, a level 60 and a level 50. The plague is at 84%. On the first turn the game takes the highest cure value (70) and modifies it by 10% of each additional cure value. (10%of 60 + 10%of 50=11 )That makes a cure level of 70+11=81, which can't cure the 84% plague outright. However, like in the first example, it reduces the plague severity from 84% to 70+10=80% (notice that the unmodified cure level is used at for this Last calculation. There's a reason for this.)

For the next turn (we'll ignore any factors which may have made the plague worse), we see that combined "cure power" of the 3 ships (70+5+6) is enough to cure the plague, which is now 80% severity.

This means that lots and lots of med ships can "gang up" on a plague to cure it. They should therefore be pretty expensive. There is a potential exploit there using the "+10 if can't cure" rule, but external severity-modifying factors will go some way to negating this.

For further complication http://forum.shrapnelgames.com/images/icons/icon10.gif a med bay's cure level is also variable over time. The base level of 30 for a med bay II could be augmented each time it successfully cures a plague (experience). Finally, medical facilities on-planet could provide a system-wide "cure boost", which alters the cure level again. These same facilities could reduce the spread of disease from planet to planet.

Finally, curing a plague outright would be a slow process. Assuming the ship or ships have a higher cure level than the plague severity, it might take several turns to reduce the severity all the way down to 0%, depending on the comparative values of the plague and cure. The same would apply when a ship reduces the severity of a plague it can't cure. This would give the plague a chance to "flare up" again if some external event prompted it.

That's about it. I know it looks horribly complicated from my explanation, but it's actually reasonable simple. Ish. From the player's point of view it would be clear what level of medical technology is required to cure a plague, but at the same time the plague would appear to have the unpredictability of an organic system. It would certainly make a lot more sense and provide a lot more challenge than the current system, anyway.

[ August 29, 2002, 16:30: Message edited by: dogscoff ]

Re: Suggestion for an improved plague model.
 

I've read through it a couple of times, and I didn't notice anything to exploit. What are you seeing?

How about, in addition to the component's cure rating, adding the ship's experience to it, and giving experience for successfully curing a plague? So a ship with cure rating 30% and 15% experience would cure 45% plagues. I think it's quite reasonable to assume medical ships would receive different training at training facilities than combat ships would. Of course, you'd have some doofus putting guns on their medical ship and hunting down lone colony ships to boost their experience, but then some people are doofuses. (Doofusi?)

[Edit/addendum]
You could also increase the risk of plague to your own planets by building plague bomb-equipped ships or launching plague intel projects (if modded in)--you know, working with hazardous biological materials more often and increasing the risk of outbreak. Just a thought.

[ August 29, 2002, 13:25: Message edited by: Krsqk ]

Re: Suggestion for an improved plague model.
 

I think you could simplify the math a little on the curing part if you gave the medical bays a cure rate.

And give plagues an infection rate.

So someone drops a lvl 1 plague bomb on your planet. It starts at 10% plagued and increases at a rate of 1% per turn. Something like that.

You then move a lvl 1 medical bay over the planet. It has a reduction rate of 2%. The percentages are then just treated like simple integers, and you arrive at a reduction rate of -1%. And you could make medical bays stack to cure plagues faster.

I'm not actually sure how you'd figure deaths, because a 10% plague will reduce your population quickly if you figure 10% dying every turn. I guess theoretically you can never get to zero population.

Dunno, just suggestions.

Re: Suggestion for an improved plague model.
 

Yeah, okay, forget all that other stuff I typed down in my original post. How about we start with this, and try to build some of the more advanced features into it:

Plague Severity:
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-All colonised planets have a plague severity value, measured as a percentage. 0% means no plague. 100% is the nastiest plague you can get.

-Every complete 5% of plague severity kills 2% of the planet's population per turn (rounded up). This means plagues of less than 5% have no effect. However, a 50% plague would kill 20 million population on a planet with 100m. The next turn it would kill 16m of the remaining 80m, then 13m...

-The severity should also affect the change in the population's anger. Low severity=slowly gets angry. High severity=instant rioting.

-Random plague events, plague bombs and plague intel would be implemented by simply adding a given value to a planet's plague severity.

-Every planet with more than 10% plague adds to the plague severity of each friendly planet in the system. Normal planets would be incremented by 1% per plagued planet per turn. Planets with a spaceport will go up by 2% per plagued planet per turn. Blockaded planets will not receive this increment.

-Ground combat on a planet increments its plague level slightly, due to homes and sanitation infrastructure being destroyed, medical staff diverted etc. The extent of the increment should depend on the duration of combat.

-Ditto for orbital bombarment, except that it's not duration but damage to population and facilities that governs the extent of the increment.

-The extent of ground/ orbital combat increments should be be subject to values in settings.txt.

-A random factor of a few percent is also introduced each turn which could be positive or negative. For planets with less than 5% severity, this random factor should lean heavily toward the negative. (ie minor plagues tend to cure themselves) It would be nice if this was moddable in settings.txt.

-It would be cool if plague could be carried by population in cargo as well, but it would probably be too hard to implement.

Medical ships & med levels:
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-All ships have a "med level" from 0 to 100. This med level takes a base value from an installed med bay component when the ship is built. Only one med component per ship is effective, but backups may be installed.

-When a medbay component is destroyed or retrofitted out, its med value is subtracted from the ship's med level.

-When a medbay component is repaired or retrofitted in, its med value is added to the ship's med level.

-Med levels are modified by experience as follows: On each planet, every 10% of severity reduction in a single turn grants 1% medical experience to every ship in orbit. Ships with a med level of 0% do not benefit from this bonus.

-A cheap "sick bay" component should be available from the start of the game with a med level of just 1 or 2.

-System and sector wide facilities could be available to temporarily modify the med levels of nearby ships.

Curing plagues
==============
-If the plague severity is higher than the med level of an orbitting ship, then that ship does not "qualify" to cure the plague and has no effect on it.

-Plague curing using medical ships is calculated as follows:
The med levels of all qualifying ships are totalled up. That total is then divided by 5 and deducted from the plague severity.

There. Much more simple, but pretty much exploit-proof and still an improvement on the existing system. Obviously the numbers could be tweaked (and modded). Opinions?

Anyone got any ideas for more advanced features tht could slot in there?

[ August 29, 2002, 16:34: Message edited by: dogscoff ]

Re: Suggestion for an improved plague model.
 

The exploit was that you could send a med ship with a cure level of 10 to a planet with a severity 80 plague. The med ship would (eventually) bring the severity down to 20, and then you could send in your other med ship (with cure level 20) to finish the job.

I like my second Version better=-) You lose the "low level ships can partially cure high level plagues" bit, but it's much simpler and maybe that could be added in some other way. It's still an improvement over the existing system.

Oh, and I love the idea of increased risks from messing around with biological weapons.

Infection rates would be cool but it would mean an awful lot more data to track. Would be very cool though.

Re: Suggestion for an improved plague model.
 

Much as I hate posting on top of my own Posts, I had to add this:

If this were to be implemented I think it would be better to turn all the numbers upside down, and rather than have "0% Plague" have "100% Health."

Is this sensible?

Re: Suggestion for an improved plague model.
 

Contagion is certainly a good idea. It's rather odd that the presence of plague on a planet does affect morale (happiness) in the entire system but it doesn't have any real chance to spread to other planets.

The percentages thing is certainly better than the flat levels we currently have but there are some other features you have not considered. Different plagues would have different rates of infection, that is, different degrees of contagion. And, why does a plague have to kill everyone outright to be damaging? What about a plague that makes everyone very sick, killing some but weakening the rest of the population and reducing production? So, 'contagion' and 'virulence' could be two completely seperate factors on a given plague. Add these two very different factors to the much finer 'scale' of effect you have proposed and things get interesting.

But there is one more thing that no one ever seems to consider. Why is it that the SAME biological weapons (or 'natural' plagues) can affect all of these 'alien' races equally??? Lizards and humans and birds and crystals all affected by the same biological agent? Is this bizarre or what? It really should be necessary to research a bio-weapon specific to the race you want to use it against. The simplest way to do this would be to have a 'named' bio-weapon for each race. But that's not the best way to do it. The best way to do it is to build some sort of 'code' system into the AI that has identifiers for the biological characteristics of the races. You could then have various degrees of 'relationship' (as in 'genetic similarity') between some races and varying degrees of effectiveness according to the closeness of the match for the bio-weapon being used.

Now THIS would get interesting if plagues could be long-standing events that infect entire systems and hang around for a while. You might see a system swept clean of one race by a plague and another race move in. Does the other race want to reclaim the planets yet? What if the plague is still there? They may be killed by it even if they successfully retake the planets by military force.

[ August 29, 2002, 20:27: Message edited by: Baron Munchausen ]

Re: Suggestion for an improved plague model.
 

The idea that a simple sick bay would cure a plague that is ravaging an entire colony of at least 34 million is unlikely, IMHO.

What I think should happen is:

3 types of plagues depending on their method of infection

Spreads by air/food/water spreads the fastest
Spreads by Touch the next
STD (Maybe... I don't know.) the Last

Then there would be 3 types of cures BASED on the sick bay component:

Sick bay cures all 3 at basic level 1-10%
Antibiotics cures Air at 10-100% must have SB to work
Chemicals cure STD at 10-100% must have SB to work
Physiotherapy cure Touch 10-100% must have SB to work

and contagion should work if there are no military ships in the system, but the rate should be increased with any transport, yours or others.

If there are military ships in the system, they work to stop the disease by:

if garrisoned on a planet, blocks that planet and moon(S) ONLY

If garrisoned on the infected planet(S) they stop the contagion for the entire empire

Just my 2 cents

Re: Suggestion for an improved plague model.
 

Actually, I've just re-read what I've written and it's full of possible exploits. i think I need to re-think it a little...

Re: Suggestion for an improved plague model.
 

Of course, you're both right about the different types of illnesses and their effects on diferent species and stuff... but it would be a massive task to implement them. Hell, what I'm suggesting is a pretty massive task, so I guess I can't really complain http://forum.shrapnelgames.com/image...s/rolleyes.gif

Anyway, I love the idea of "blockading" your own planets to prevent the spread, and of adding a flat increment to contagion rates according to the number of population transports.

As for production... Well hapiness would modify production, and be directly affected by plagues, but why not just go a step further and multiply production by health? 50% health * 1000 minerals would adequately represent all those workers unable to go to work...

I'm going to compile all the ideas from this thread, and then when the thread dies off I'll mail the whole bag to Malfador...

<font size="2" face="Verdana, Helvetica, sans-serif">Well... yes and no. Firstly I think the medical bay is supposed to be more than a simple sick bay. All ships would have a sick bay as part of the crew quarters, which would deal with the crew's health and nothing else. You could model this with a component with a med level of just one or two. It wouldn't cure much on it's own, but it might be able to help out in a large scale effort involving more specialised ships.

A medical bay, on the other hand, would be a large facility specifically designed for the kind of tasks we are talking about. Whether or not that single ship could cure an entire planet... I don't know. Star Trek certainly seems to think it's possible=-) If they had the very latest technology and the best staff (which is kind of implied by the research points you spend to get it), then they might be the first to come up with a solution which can then be administered by the local health authorities. It's hard to say. Th e thing to remember though, is that it's an abstraction. It's a way of representing the fact that you (as emporer) are diverting resources into helping the problem on planet X. You could argue all sorts of "invisible" support for that ship, just like the "invisible" transports which move your resources all over the place.

Anyway in light of all this, I think that med bays should be larger and/ or more expensive. http://forum.shrapnelgames.com/images/icons/icon7.gif

[ August 30, 2002, 09:46: Message edited by: dogscoff ]