GIS and navigable rivers

[mskala at ansuz dot sooke dot bc dot ca]

On Sat, 1 Jan 2005, Lincoln Peters wrote:
> developed areas as part of the terrain, whereas Xconq would usually
> treat them as units.  As I think about this, the solution would
> ultimately depend on the scale of the game and the resolution of the

> 2. Handling rivers from GIS data: Should they be cell terrain, border

I think both these issues illustrate my point that GIS->game conversion
really depends on the game.  If we're going to do it automatically, I
think we should give the designer a lot of control to specify just what
conversions should be done.

> like Advances, Ancient Greece, or Ancient Rome, you'd probably want to
> set up rivers so that they would simultaneously impede movement of land
> units and allow movement of certain naval units.  As far as I can tell,

There's some discussion of the navigable-rivers issue in the designer's
manual; if you make them borders so that they can impede land movement,
then it's tricky for ships to travel along them, and if you make them
connections so that ships can travel along them, they won't impede land
movement.  The documentation suggests making a chain of alternating lake
hexes and river borders, and using the special "border slide" movement
mode.

Another thing one could do, although it's something of a hack, is to
represent a river by a connection type *and* a border type, going in lines
parallel to each other; the graphics could be designed either to make one
of those invisible, or to make the two of them together look like a single
river.  That's actually quite an attractive idea; I think I'll try to find
some time to design a sample game illustrating it.

I think it would be worth researching what the old-style tabletop hex-grid
games did about this issue, since they would have faced it too.  The ones
I'm familiar with did it in a makeshift way by having rivers be what XConq
calls connections, and having the land within a cell containing a river be
split into two chunks, with players required to keep track of which bank a
given unit is on.  I think that would be prohibitively difficult for XConq
because it means changing the topology of the grid entirely.  But there've
got to be games that handled it in a more computer-friendly way.
-- 
Matthew Skala
mskala@ansuz.sooke.bc.ca                    Embrace and defend.
http://ansuz.sooke.bc.ca/