Advanced informations for building reqirement

First of all thank you for the mod! I really enjoy playing it from time to time, mainly because of the many various buildings and techs.

But after 30+ technologies are explored, I - personally - loose track of the building requirements (E.g: I want to build a specific wonder or building but i need to click myself through 2 or more "layers" till I find the first buildable one to get started).

My suggestion (or question, if it already exisits) would be a "techtree" for buildings. Because not all buildings are based upon one source several trees would have to be created. A nice basis would be the resources itself branching into processing buildungs of different ages (e.g. Hemp --> Cloth factory || weavery). Cultures, wonder etc. could be appended at the top as many of them require one or more of a building type.

There is a page with the upgrade tree for buildings but not one for requirements.

edit I would like one which shows the manufacturing tree of raw resources to manufactured resources showing the buildings needed. EG carcass (Resource) -> slaughterhouse (Building) -> butchery (Building) -> raw meat (Resource). In theory this should be possible with the current code but I have not tried it yet.
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In theory several classes would be needed:
-> A getter-object for the building properties (XML_file?)
-> A class to add/modify civilopedia (i refer to the one ingame, not the one in the menu)
-> A function/class to build several tree objects, and a storage class (like the "lists" for filters and sort)

Conerning design:
A) Integrate into civilopedia (where techtree, building list is -> or replace building list,...). Two avoid long loading times, a list of the resources should be displayed; from its selection the requested processing tree will be shown.

B) additional to A) each building could include a link to its processing tree(s) to its description page (same for wonders/resources??). At this point the whole idea becomes overly complex and bloated (search function: right tree for the right building, amount of items to process per request).

There is a bug in the building page of the pedia which is slowing things down. I have not had time to look at it.

There is only one pedia. The one in game is the same as the one in the game. Some entries may not be there in game because of the options chosen may turn the building/unit off.

The tree pages, ie building/unit upgrade trees, use the same code but have different inputs. The building and its upgrade form the set of linked pairs and that is passed to the code that builds the trees. In theory we could make the sets "resource used by building", "building makes resource" and "building requires building" then pass this to the code to make the trees.

edit The problem would then be in linking the icon to the correct pedia entry ie building or resource. Or it may not be a problem at all.

Of course the real problem would be those buildings with multiple "or" requirements. How do you show them?

Then there are the buildings that require the resource in the vicinity of the city and those that require a terrain or terrain feature.

If the building is only linked to its upgrade and not its requirements, then perhaps the requirements can be accessed through the building object itself. On the other hand the "additional elements" (terrain, resources, city size, culture) must be added to the element in the tree manually ( if this is even possibly, i did not find the class actually).