[Freeciv-Dev] mountains versus plateaus

[Jason Dorje Short <jdorje@xxxxxxxxxxxx>]

http://freeciv.org/~jdorje/mountainous.png

This gen5 continent is full of mountains.

In real life though these wouldn't be mountains.  A flat plateau is 
still flat, no matter how high it is.  SMAC had a reasonable model of 
this with altitude being a measurable and visible part of the terrain. 
But even with a simpler model we can do better.
Terrain placement depends on rockiness (or perhaps slope), temperature, 
and moisture.  However none of these are independent values. 
Temperature depends on lattitude but also on altitude.  Moisture depends 
on nearby bodies of water, nearby wind blockers (mountains), prevailing 
wind direction, and pure altitude.  Rockiness/slope can perhaps be 
determined solely by comparing the altitude of this tile to that of 
adjacent tiles.
In some cases altitude itself _might_ be a factor in terrain placement. 
 Swamp and grassland _may_ be limited to lowlands.  Of course ocean 
placement depends entirely on altitude.  And mountains probably have a 
minimum altitude (since they are at least partly above the "tree line").
In summary the above continent shouldn't be full of hills.  It should 
probably be a ring of hills or mountains with a plateau of plains or 
desert at the top.  The exact threshholds will need tweaking.  But the 
current method of placing mountains is pretty broken.
jason