After bug #16855, clicking the new "Show all" button in the research report
with the "multiplayer" ruleset caused infinite recursion.

Patch by Matthias Pfafferodt (syntron@gna).

See gna bug #17555.

(Browse SVN revision 19098)

Awake again some comments:

> At the time of my original submission I was experimenting with a
> possibility to force tech-traders to aquire all requirements
> before they can get the one they are after.

Could a similar lua script as mentioned in comment #7 help? You would need a self-rooted tech and a lua signal if a tech is reserached. The script would need to check all requirements (the techs of this erea) to give the player the (free) 'next erea' tech. I'm not sure if this is possible at the moment as you would need to check if the player has researched specific techs. Perhaps an additional lua function is needed.

Thus, no change to the interface is required - you can do it by using only ruleset code (techs as well as lua script).

> Raised as bug #17555, thanks. (Initially assigned to me but
> feel free to steal it.)

You can commit it. But do remember the time frame for 2.3.0 ... ;-)

I'm just back from a short trip with little sleep ... so here is my idea how to solve it: Could you add the following check to player_invention_reachable() (common/tech.c)

If this works, please add it as a new ticket for 2.3.0!

Although the case is closed I'd like to add a comment...

I think the visibility of unresearchable techs should not be allowed to be decided by the player. Rather, it should be made as a ruleset option. It is the ruleset desiger who adds the root_reqs, so they should know if tech are to be visible in tree before they can be researched or not.

At the time of my original submission I was experimenting with a possibility to force tech-traders to aquire all requirements before they can get the one they are after. That could be achieved by root_reqqing every single tech in the tree. In this case the unresearchable ones should be visible in the tree.

After that I've come up with an idea of technological eras. That means that there could be some critical techs in the tree which would reveal a bunch of new ones. Maybe making the research also harder from that point forward.

So my original bug report was a bit too one-sided. I'm happy that you noticed that and made the visibility thing choosable. Only I disagree with the part who gets to choose. :p

show all techs or only reachable techs

• start with only reachable techs shown

see gna bug #16855
reported by HanduMan

(Browse SVN revision 19057)

show all techs or only reachable techs

• only one small string added ('show all')

(file #12005)

If root_req property has been defined for certain advance in a custom ruleset, that advance will not be visible in research report (F6) until the player has aquired the root_req tech. Also all future techs in the branch limited by this root_req are missing. This would make sense if the root_req was a non-researchable tech but it happens even if the root_req is a normally achievable one.

All technologies that are achievable in normal manner (researched, traded, stolen, hut) should be visible in the tech tree. Maybe some kind of indication of the existing root_req would be nice?

Also, the help system for technologies will not handle root_req'd tech tree properly. It cannot calculate the needed number of other techs nor amount of bulbs. It seems to list all the right prerequisites but shows only '1' for the count. (Should this be reported separately?)