[Freeciv-Dev] Re: (PR#12719) Automaticaly generated techtree diagram

["Vasco Alexandre da Silva Costa" <vasc@xxxxxxxxxxxxxx>]

<URL: http://bugs.freeciv.org/Ticket/Display.html?id=12719 >

On Tue, 5 Apr 2005, Mateusz Stefek wrote:

>
> <URL: http://bugs.freeciv.org/Ticket/Display.html?id=12719 >
>
> The attached screenshot tells everything.
>
> This doesn't look like diagrams in commercial games, but it is step
> forward. I belive that with good tileset support it could look much
> better.
>
> There are many improvements which should/could be considered:
> - icons in rectangles
> - tooltips
> - making the diagram interactive
> - recentering on current tech goal
> - beter algorithm for dividing tree into layers
>
> I tried to divide the code into three parts: combinatorial,
> calculating layout and drawing. It should be easy to add improvements
> into one part without touching the rest.

I like the idea, but I think this should be a GTK+ widget. Then we could
submit this to GTK+ proper.

This Tk widget:
http://arch-http.hq.eso.org/~abrighto/tree/tree.html

Has source code and the author has licensed it under what is basically a
BSD license without the license clause.

It is based on:
IEEE Software: July 1990 "Drawing Dynamic Trees"

I have no access to that without paying, perhaps one of you who is in an
university or research institution can arrange access easier via your
library in case you are interested.

I did find this survey online however:
http://www.cs.brown.edu/people/rt/papers/gdbiblio.pdf

X Window System Xaw also has a Tree widget, but the license seems to have
the obnoxious BSD advertising clause which is incompatible with the GPL.

Sun Xview/Openlook also had a tree widget, but the license for that seems
to have some patent clauses, which while interesting, probably make the
whole thing GPL incompatible.

PS: This does not that mean your patch cannot be commited as an interim
solution.

---
Vasco Alexandre da Silva Costa @ Instituto Superior Tecnico, Lisboa