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Topic: Making wild animals reproducible

Nordfriese
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Posted at: 2020-02-22, 16:30

The control mechanism suggested above would work only if there is a balance of carnivores and herbivores on the map to begin with

I rather think it would work better on maps with no such balance than an algorithm with just plain chances

(because I assume that game keeper doesn't favor any animal species and thus doesn't alter balance).

Yes he does: he creates only bunny chamois deer elk reindeer sheep stag wildboar wisent

I think that it would be nice for the player to be able to maintain animal resources by having forest areas and from time to time stopping hunting to avoid overhunting

That would IMHO be a too big change to tribes balance. animal breeding should be a small feature with almost negligible gameplay effect.

Maybe hunters could also have a bit of intelligence: if there's less than three animals of any species on the hunting area, the Hunter does not hunt those species as long as there's meat in the stock.

Very hard to implement… the hunter only looks for map object with the attribute "eatable" with no other considerations…


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king_of_nowhere
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Posted at: 2020-02-22, 17:46

Solstice_s_Return wrote:

Low values should work like a control mechanism in itself, but careful consideration is absolutely necessary. The control mechanism suggested above would work only if there is a balance of carnivores and herbivores on the map to begin with (because I assume that game keeper doesn't favor any animal species and thus doesn't alter balance). However, most propably there is imbalance to begin with and so that kind of control mechanism might not work very well.

wrong. that's exactlyt what a self-regulating mechanism avoids.

see, let's assume that at the beginning there are too many predators. so the predators will be unlikely to run into prey, and they will start to die off. thinking on it, prey would also be unlikely to run into each other to breed. so perhaps they should be allowed to breed even without meeting anyone else, after a random time.

while if there are too many prey, then predators will eat abundantly and will replicate pretty fast, until they cut down prey population. then they will also start to die off.

only if all predators or all prey are hunted to extinction you will have runoff.

it's how it works on actual ecosystems, and they generally regulate themselves.

Low values and the fact that breeding takes place only in forested nodes would most likely prevent runaway problems exept maybe on maps with very high coverage of forests.

again, wrong. the more animals you have, the more likely that two of them will meet on the same corner. so, animals will face an exponential growth. it starts slow, but at some point you get every single corner filled with animals. who will stumble upon a viable partner at every step, thus reproducing continuously. that's a runaway effect.

in fact, it may probably work better if chances to reproduce and to escape a predator were both affected negatively by other critters of the same kind in a 20-corners radius.

Too bad i haven't see einstein in a while. he would make a full mathematical model about it and calculate everything.

Currently it is very typical that animals go extinct during the game, so a runaway extinction problem is already there.

yes, that's what happens when you overhunt. it's one of the few realistic parts of the game.


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Solstice_s_Return
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Posted at: 2020-02-22, 18:45

king_of_nowhere wrote:

Solstice_s_Return wrote:

Low values should work like a control mechanism in itself, but careful consideration is absolutely necessary. The control mechanism suggested above would work only if there is a balance of carnivores and herbivores on the map to begin with (because I assume that game keeper doesn't favor any animal species and thus doesn't alter balance). However, most propably there is imbalance to begin with and so that kind of control mechanism might not work very well.

wrong. that's exactlyt what a self-regulating mechanism avoids.

see, let's assume that at the beginning there are too many predators. so the predators will be unlikely to run into prey, and they will start to die off. thinking on it, prey would also be unlikely to run into each other to breed. so perhaps they should be allowed to breed even without meeting anyone else, after a random time.

while if there are too many prey, then predators will eat abundantly and will replicate pretty fast, until they cut down prey population. then they will also start to die off.

only if all predators or all prey are hunted to extinction you will have runoff.

it's how it works on actual ecosystems, and they generally regulate themselves.

Low values and the fact that breeding takes place only in forested nodes would most likely prevent runaway problems exept maybe on maps with very high coverage of forests.

again, wrong. the more animals you have, the more likely that two of them will meet on the same corner. so, animals will face an exponential growth. it starts slow, but at some point you get every single corner filled with animals. who will stumble upon a viable partner at every step, thus reproducing continuously. that's a runaway effect.

in fact, it may probably work better if chances to reproduce and to escape a predator were both affected negatively by other critters of the same kind in a 20-corners radius.

Too bad i haven't see einstein in a while. he would make a full mathematical model about it and calculate everything.

Currently it is very typical that animals go extinct during the game, so a runaway extinction problem is already there.

yes, that's what happens when you overhunt. it's one of the few realistic parts of the game.

Then it would depend from the die off speed and long die off times would not be good as was suggested earlier.

I know that in reality it would work pretty much like that when there's no human influence involved. However, for example here in finland there's way too few carnivores to control herbivores in case we'd quit hunting entirely. But yes, after some more consideration I think you're right with your simplified model.

But how about even more simple (and less realistic) model to keep things less resource intensive for computers: The total amount of wild animals can never exeed the total amount of trees on a map. I assume that the program already knows how many animals and trees are on each map. Then there would be just two numbers to compare and if there's less trees than animals, they start to die. In this case the die off time could be long without any problems.

Edited: 2020-02-22, 18:50

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JanO
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Posted at: 2020-02-22, 19:48

I think a 100% chance of preying + an adequate chance of reproduction for herbivores would affect gameplay not just a little bit. If we want that, we have to consider the effects on all tribes and do the necessary adjustments, which might be ...some more of them.
I also think of computation time. I guess it might make sense to stay with approaches that only calculate one event (reproduction or prey) when two animaly meet. Giving most of them something like an age might cause problems on large maps or do I overestimate this?


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the-x
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Posted at: 2020-02-22, 19:55

We should have a look that we don't make to little changes we wont see later or recognize in game but have high programming work, which is indeed needed for so many projects (Build 21, Amazons gameplay, graphics for Amazons) atm


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Nordfriese
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Posted at: 2020-02-22, 20:03

We should have a look that we don't make to little changes we wont see later or recognize in game but have high programming work

Good point.

In my opinion, we should keep the effect on the game small. This means no fancy things which are hard to implement. But the following should be pretty easy to code:

  • give each critter a tag "herbivore"/"carnivore"

  • when a critter with carnivore tag enters a field with one or more herbivores on it, one herbivore is eaten with say 25% chance

  • when a critter with herbivore tag enters an immovable with the new "herbivore_food" tag (given to Tiny, Small and Medium fields only), the immovable's currently running program step runtime is increased by say 5s

  • critters remember their creation gametime and die when they reach a critter-specific lifetime defined in their init.lua

  • when a critter enters a field, and there is another critter of the same type on it, and both critters are at least say 20 minutes old, and there is also an immovable tagged "tree_any_growth_stage" on it, another critter of the same type is spawned on the field with say 25% chance

Those should be pretty easy to implement and are worth the effort even if the impact on the game is small. More complex models are not really worth their effort IMHO.

Edited: 2020-02-22, 20:03

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simplypeachy
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Posted at: 2020-02-22, 20:19

I still remember the tree mating fun, which left maps crammed with trees. On larger maps and areas without player predation this could generate a lot of clutter and CPU work. If free animals are going to be added, the implications on each tribe's food requirements need to be considered and rebalancing also included as this feature acts as a greater benefit to some tribes over others.

Most importantly I don't see what this adds to the game.


I need less fish :-(
Update: I definitely need less fish :-((
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WorldSavior
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Posted at: 2020-02-22, 20:33

Now the arguments of the-x and simplypeachy conviced me that it would be the best to not touch anything here, it would be just a waste of development work.


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PkK
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Posted at: 2020-02-22, 20:54

IRL, larger (i.e. the sizes of animals represented in-game) herbivores do best in a mixture of grasslands and forests. They need the forests for protection from predators, and the grasslands for grazing. It would be nice, if this could be reflected in-game.


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king_of_nowhere
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Posted at: 2020-02-22, 21:04

WorldSavior wrote:

Now the arguments of the-x and simplypeachy conviced me that it would be the best to not touch anything here, it would be just a waste of development work.

yeah. it would be nice to have this slight effect of animal population slowly recovering over time if you stop your hunters, but not worth the effort at the moment. especially with more important things to prioritize.


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