[Freeciv-Dev] Re: I have written a new terrain generator

["Ross W. Wetmore" <rwetmore@xxxxxxxxxxxx>]

Karen Yeats was experimenting with something along this 
line a year or so ago with a friend. If she sees this, 
or you check the Freeciv mailing lists for her email, I 
suspect she would be quite interested.

The corecleanup devapth also has a number of fairly 
extensive changes to mapgen.c to enhance and make it 
easier for the current generators to share certain 
mk<feature> elements. Modular routines in this flavour
would almost certainly fit into the current system
and could be expanded on as rules based building blocks.

Temperature and wetness are high on the priority list of
extensions to make more geographically sensible maps.

Corecleanups use an "asteroid" rain analogy to build up
heightmaps with various localization techniques to bias
random hits by elevation, etc. 

Thus there seem to be lots of parallel ideas in your 
description and it would be quite interesting to see how 
you have done the implementation.

There has also been some talk of reorganizing the map
generation to add at least a new generator capable of
fully dealing with the various topology patches, and
make generator addition much more modular in the process.
Finding people willing to make new generators or with
generators of their own with novel requirements might
kickstart this and get it moving again.

By all means upload your changes to freciv.org and post
a note, or put them someplace accessible. I for one will
be happy to have a look at them and post a review or
just send you comments if you prefer.

If the code is useful or there are useful elements, ideas 
or potential and you are interested in pursuing this,
submitting your package or parts of it as patches would
be very useful and appreciated. Help from other developers
is almost always forthcoming on any problem areas if you 
just ask, either on the list or by private email.

Cheers,
RossW
=====

At 02:22 PM 02/04/26 +0200, Helge Hafting wrote:
>I have written a new terrain generator, and wonder
>if there's any interest in testing it,
>and where I should send the files.
>
>My terrain generator tries create a natural terrain by
>simulating global weather.  The simulation has
>lots of adjustable parameters, currently stored in a
>file of its own.
>
>The first step is creating a height map.
>That is, each tile  gets some height or depth.
>Heights are averaged to simulate erosion.
>
>The next step is to assign tile temperatures, depending
>on latitude and wether the tile is land or sea.
>And high tiles are colder than low ones.
>Temperatures are then averaged, i.e. sea tiles
>influence nearby land and vice versa.
>
>The third step is a simulation of weather.  
>Water evaporates from sea (and tiles wet from
>previous passes) and form clouds that rain down
>on neighbour tiles.  You get more rain
>over cold and high tiles, as in real life.
>Tiles end up with different wetness after this.
>
>The fourth step is to run excess water down
>to lower tiles until it reaches the sea.  
>Any tile with sufficient waterflow becomes
>river.
>
>The final step is to map the generated terrain
>to freeciv tile types.  This is done by using
>a ruleset that specify a height range, a
>temperature range, and a wetness range for
>each freeciv tile type.  These rules
>are in the config file too, so they can
>be tuned easily.  And new tiletypes may
>be added without changing the program code.
>
>The generated terrain have rivers flowing 
>from mountains to sea, and mountains
>mostly in the middle of continents.
>
>The program is currently standalone, it
>reads a savegame to get some 
>parameters like land percentage and
>then rewrites the terrain.  I wonder if it is
>interest in having it merged as another
>way of generating terrain?
>
>I can do it, but I will probably need some
>advice.  I haven't used CVS before, and
>there are some issues.  The current terrain
>generator do stuff like deleting small islands.
>I don't know why, it is easy enough to put
>the players on larger islands or perhaps
>give the "unlucky" ones a free trireme
>or something.
>
>Helge Hafting