Is this a bug or I'm missing something??

[Zebek]

Last night, while starting a new game, i noticed something strange that never noticed till that moment.

In the first turn I had my science bar to 100%, as allways, then i was getting all my comerce points into beakers, 9 of them. I multiplied that amount for the number of turns that shows the tech bar and.... the result was less than needed !!!

Let me show an example: (im sorry, i use the spanish version)



9 beakers x 12 turns = 108 !!!

I check my city and find that:


9 ! as i saw before... 8 from palace and 1 from city tile.

now, the financial screen:



Still 9 !! Whats happening here??

Next turn mistery gets more interesting:



12 !!! I got 12 beakers ! How its that possible??

I started some games more at different levels with the hope thats one of those level bonuses, but.... it still happening in the high levels. In fact, this example has been took from a Deity game (Deity-Standard-Normal)

Someone can explain if its a bug or not?

Edit: Just posted this and remember somethig I read, can't remember where, about bonuses to research techs that IA had reserched.... or not... or something like that, ...bah

Anyone knows that?

[LordShiva]

Yeah, research boni on techs already researched by someone else.

[Jaybe]

LordShiva, that does not quite answer the question, because ...
even in the modern age when I am tech leader if I multiply my research (in F2) by number of turns remaining to gain the tech, it still often comes up short of the research remaining.

There is something else to the equation that is yet unknown (assuming it is not a bug).

[Nacht]

You can get two research cost modifiers.

The first is the TECH_COST_TOTAL_KNOWN_TEAM_MODIFIER which is defined at 30 in an XML file.

This means that if every player has already discovered the tech you're researching you get a 30% reduction, if half of them do you get 15%. Since you are yourself a player you never get the full 30%. In a game with 6 player 25% is the most you can get.

The second is the TECH_COST_KNOWN_PREREQ_MODIFIER defined as 20.

Meaning if you've researched all prereqs you get 20% reduction. The six starting techs don't have any prereqs, so you always get 0% for them, some techs have one prereq so you always get 20% reduction otherwise you couldn't research them. Some techs like writing have 3 prereqs, for those techs this constant matters somewhat.

Another weird thing is that if you have at least one city you get one beaker for free. Try it, once you have one city you cannot completely halt your research. I suppose that is to avoid some divide by zero errors.

The COST_MODIFIER in those constants are somewhat misleading in that not the cost but the number of beakers you produce are modified. (leading to possible overflow exploits)

for your examples Zebek: your screenshots don't show what you are researching, it could be Archery. Archery has one prereq Hunting. You get a 20% reduction. Your research is 9, add the one bonus beaker +20% and you have 12.

Simple isn't it

[Jaybe]

Thank you Nacht, for the enlightenment.
I do wish that those reductions (bonuses, rather), were added to the research figures.

[proviisori]

Originally posted by Nacht
for your examples Zebek: your screenshots don't show what you are researching, it could be Archery. Archery has one prereq Hunting. You get a 20% reduction. Your research is 9, add the one bonus beaker +20% and you have 12.

Simple isn't it

I don't understand spanish much, but my guess is that "Meditación" is Meditation.

[Nacht]

Originally posted by Jaybe
I do wish that those reductions (bonuses, rather), were added to the research figures.

I agree. Maybe they thought that varying figures on the tech tree would be confusing. But I think that being able to divide those figures by your total amount of beakers and actually get the right number of turns would be more transparant. Well at least for those that bother to check
These modifiers could be very well some last minute balancing solutions, without having time to give an ingame 'explanation'.

Originally posted by Flamer(fin)
I don't understand spanish much, but my guess is that "Meditación" is Meditation.

Luckily for me meditation also has one prereq

[Diadem]

The known techs modifier only counts civilizations you have made contact with. And the known prereq modifier is only for optional prereqs.

Both should be 0 in Zebek's case. He's researching a tech noone has yet, with only 1 prereq, so no optional ones.

So ... that can't be it.

[Zebek]

Many thanks for your posts guys !!

I had read your posts carefully and think your answers are very interesting and maybe some of that its going on that way but i tried to start another game, now with Churchill. This leader starts with minery and if I start researching Bronze Working im still having this bonus !! I hope no other Civ has this tech at the first turn !!

Checking all the possibilities at the first turn with Churchill I got:

- Sailing, Masonry and Bronze working, gave me 12/turn

- The Wheel, Agriculture, Hunting and Mysticism 10/turn

So, it looks like at "this case" prereqs have some influence and discovered techs not (at least at this first turn), but still having more beakers at non-prereqs techs, can someone explain that??

[Nacht]

Originally posted by Zebek
This leader starts with minery and if I start researching Bronze Working im still having this bonus !!

Of course, the 20% prereq bonus.

Originally posted by Zebek
- The Wheel, Agriculture, Hunting and Mysticism 10/turn

I forgot to mention that the known tech bonus only applies if you've really met those civs. So no bonus on your first turn. This is very bad for those poor civs alone on a continent.

[Zebek]

Originally posted by Nacht

... So no bonus on your first turn....

No, i got it !!! my city was producing only 9 commerce units !!

thats what i cant understand.

[Nacht]

Originally posted by Zebek
No, i got it !!! my city was producing only 9 commerce units !!

thats what i cant understand.

Originally posted by Nacht
Another weird thing is that if you have at least one city you get one beaker for free. Try it, once you have one city you cannot completely halt your research. I suppose that is to avoid some divide by zero errors.

[Diadem]

But the prereq bonus should only apply to optional prereqs.

Mining shouldn't give a prereq bonus to bronze working, it's a required tech, not an optional one. Thinks like pottery and priesthood should give a bonus to writing if you already have animal husbandry - each tech allows an additional path to writing, and thus gives you a bonus.

At least that's how I have always understood it.

[Diadem]

I did some testing. And the prereq bonus works entirely unlogical.

Researching Mining: No prereq bonus
Researching Animal Husbandry: 20% bonus
Researching Pottery with The Wheel and Agriculture: 20% bonus
Researching Pottery with The Wheel, Agriculture & Fishing: 40% bonus
Researching Pottery with Agriculture & Fishing (NOT the wheel): 40% bonus
Researching Pottery with JUST The Wheel: no bonus


So it looks like you get 20% bonus for any prereq that is not shown with a little icon at the top of the tech. So while mining is a required tech for bronze working, you do get a bonus for it. But you never get any bonusses for flight.

This seems rather stupid to me. There is no difference at all between a tech that is required because it's shown with an icon, or a tech that is required because there's no other route. If you check the civilopedia you will see that they are displayed in exactly the same way in it. Yet the game does give you a different bonus.

Oh well. Just another one of those weird inner workings of civ4

[Nacht]

Originally posted by Diadem
But the prereq bonus should only apply to optional prereqs.

Mining shouldn't give a prereq bonus to bronze working, it's a required tech, not an optional one. Thinks like pottery and priesthood should give a bonus to writing if you already have animal husbandry - each tech allows an additional path to writing, and thus gives you a bonus.

At least that's how I have always understood it.

Yes, you would expect that, isn't true though. The prereqs that are indicated by an icon on the tech chart are the AND prereqs, the arrow prereqs are the 'OR' prereqs, even if there's only one arrow. So for any tech with one arrow you always get 20%.