Pre-alpha version of a coating-based terrain module

[Lincoln Peters <sampln@sbcglobal.net>]

I've given up on implementing bodies of water as coatings (I'll make
them cell terrain), I've given up on soil composition (at least for
now), and I've re-implemented climate as cell terrain.  It's still a
rather complicated terrain module, and it has a ways to go before it's
usable, but it should offer at least a general idea of what I'm trying
to do.

You can download it at:
http://homepage.mac.com/lmpeters/omniterr.g

Right now, it's probably usable for the Xconq/GIS project, but for
anything else, the following issues need to be addressed:

1. The existing code for generating maps does not allow me to place
climate zones in a realistic manner.  Currently (though this may be
partially due to the means by which I laid out terrain), it sees nothing
wrong with placing a "tropical wet" zone right next to a "polar ice cap"
zone!  Eventually, I would also need a way to ensure that, for example,
a random map does not place a Mediterranean climate on the east coast of
a continent (Mediterranean climates are *never* found on the east coast
of anything).

2. There needs to be a synthesis method for applying coatings to terrain
when the coatings are unlikely to change over time (as would be the case
when climates and vegetation are defined as coatings).  Perhaps some way
to run the make-fractal-percentile-terrain (or a variant thereof, as per
#1) on coatings after running it on cell terrain?  (For now, I'm not
even going to consider making dynamic coatings work!)


The following issues affect the Xconq/GIS project, although they would
not necessarily preclude the use of this module for that project:

3. I opened the module in "Design" mode, since I could then apply
coatings to cells manually with little fuss.  I discovered that, when
multiple coatings exist on one cell, only the coating defined first in
the module will appear.  For example, if you apply a "savanna grass"
coating to a cell, followed by a "rain" coating, only the "savanna
grass" coating shows up on the map (both show up correctly in the text
on the "description" bar).  There needs to be a way to display multiple
coatings simultaneously on the map.

4. There need to be terrain images that would correspond to each of
these 20 different climate zones (not to mention the 8 types of
vegetation, though they tend to be specific to one or two climate
zones).  If you don't understand why, try running the module and notice
the color scheme I had to use!*

5. As soon as I put some real-world figures into the temperature
definitions, I found snow spontaneously appearing, due to the hard-coded
hack that was used to make ww2-eur-42.g work!

6. While trying to make the best of the unexpected snow, I discovered
that, when a cell is in night conditions, coatings are *not* drawn at
all.  Weird.


* Actually, I didn't try very hard to make the terrain images look
good.  At the moment, they're each basically the same color that is used
in the color-coded map I was studying while writing the GDL code, and it
didn't turn out very well.

---
Lincoln Peters
<sampln@sbcglobal.net>

A committee takes root and grows, it flowers, wilts and dies, scattering the
seed from which other committees will bloom.
		-- Parkinson