TOPIC:

ImpCre - Imperium world builder

DESCRIPTION:
(Where the term "world" is used, it refers to the whole Imperium
"universe", meaning all planets, stars, black holes, etc. A reference
to a specific item will be stated like "Planet xxx".)

ImpCre is the utility used to build up worlds for Imperium. ImpCre creates
a world by checking various environment variables (usually set through a
shell script) to determine what kind of world to create. Then it uses
heuristics to determine whether the world it has generated is "fair", and
meets your requirements. It should therefore (hopefully ?) not be necessary
to visually look at the world it has generated, although you may do so
if you wish.

NOTES:
Note that a 128x128 world, using the defaults, will generate over
2.8 megabytes of data, on the average, and that a 256x256 world
will generate over 12 megabytes of data, on the average.

However, due to the way that ImpCre generates the planet data, it will
seldom be required to actually read all this data, and so game access
is still quite fast.

Basically, ImpCre builds the planets (and stars, but I will just call
them planets here) working from the top-left corner, moving downwards
as you would read an english page, generating any planets needed by
the sector as it goes. Therefore it will seldom be required to read
more than a few objects which occur next to each other in the
database, and due to the ImpServ caches, file seeking should be
minimized. For example:
Sector 1,3 might contain planets 25-31
Sector 1,4 might contain planets 32-35

In order to maintain this data layout and optimization, the deity
should refrain from adding any planets or stars to a sector as much
as possible, or add them only in relatively unused sectors where there
won't be much need to access them. For example, if the deity adds
even one planet to a sector, you could end up with something like
the following:
Sector 1,3 contains planets 25-31 *AND* 62341
which will now require a jump much farther into the planet file each
time the sector is updated. How long the jump takes will depend on
how fast your hard drive and controller are; how fragmented your
planet file is, how many users are also playing; etc. It will normally
only take less than a second, but this can add up if you have many
such gaps.

Creating a world

You should first start out by copying one of the existing example
shell scripts in the "ImpCre" directory to a name that represents
the type of configuration you intend it to have, such as "dense1.sh"
or "megastars.sh". Then edit the file and change the various settings
to whatever you like.

- The many settings you may change are described below. -

Once you have gotten all the options the way you want them, you
simply execute the shell script in the directory you want the "base"
(telegrams, mainly) to be located in, and ImpCre will try it's best to
create the world you requested.

If it is unable to create what it considers a "fair" world, it will
let you know, and you will have to try changing the values in the
shell script and running it again. If ImpCre fails once with a certain
group of settings don't give up. It may be possible to create the world
if you try it again with ImpCre using a different random number seed.

If you create a world in a directory that was a previously used to
hold an Imperium world you should be sure to delete all the news
("news.*" files) and propaganda ("prop.*" files).

If ImpCre is able to create a suitable world, it will be displayed
to stdout, and you will be asked if you wish to create the world
files. If you like the world you can answer "yes" and ImpCre will
write the world for you. Make sure you have enough disk space!

Tunable World Parameters

There are many settings that you may change while deciding what you
want your new world to be like. Additionally, there are MANY more that
may be changed from within Imperium itself after the world has been
created. At one time I was considering allowing you to specify them
all at world build time, but just a quick estimate told me it would
require over 20 80x25 screens just to present them all. If you really
think you would like this ability, let me know. The settings that you
may change from within Imperium are listed and described in the
"Factors" doc file, should you wish to change them.

Following is a description of what each of the items you may enter do.

Horizontal size of the world
This is the number of "galactic" sectors WIDE the world is. Remember
that each galactic sector is broken down into 10 "subsectors"
horizontally. Minimum of 10, max of 255.

Vertical size of the world
This is the number of "galactic" sectors TALL the world is. Remember
that each galactic sector is broken down into 10 "subsectors"
vertically. Minimum of 10, max of 255.

These two settings will affect other parts of the world
generation, such as the maximum number of players, etc.
Also, the two sizes do NOT have to be equal.

MaxTries
This will be determined automagically based on the world size, but if
you need to override it due to your settings affecting star, planet,
or "other" density, you may. Basically this is the number of times
that ImpCre should loop while trying to construct the initial layout
of the world. If a world can't be created after this many placement
attempts, ImpCre will try to start over from scratch. If you want to
see what number is currently being used, specify the "-v" flag on the
ImpCre command-line.

Number of players
This is the number of players that you want to allow before "reusing"
idle accounts. This can be increased later, if you run out of virgin
player slots, but don't want to remove idle players. Primarily this
is just here to give you an idea of about how many players can use the
game without having to bump into each other all the time. If you find
that some players aren't very active, you can increase the limit
later.

Percent of "other" sectors
This the percentage of the total number of galactic sectors that should
be black holes or super novas. This includes all 100 "subsectors", so
each "other" sector that exists in the world will reduce your usable
subsectors by 100, and will increase the odds that ImpCre will not be
able to place things fairly.

Percent of "other" sectors that should be black holes
This will determine how many of the "other" sectors that get created
will be black holes versus super novas. Supernovas instantly destroy
any ship that passes through them. Black holes can do various random
things like destroying a ship, causing a ship to appear in another
part of the world, changing the owner of the ship, contaminating the
ship with the plague, etc.

Percent of sectors with at least 1 star
This is the percentage of sectors that will have at least one star
in them. A sector with no stars will never have any planets in the
sector.

Percent of sectors with more than 1 star
This is the percentage of sectors (with the maximum being the above
percentage) that have more than one star in them. Sectors with more
than one star will tend to have mineral-rich but atmosphere-poor
planets.

Percent of sectors with at least 1 planet
This is the percentage of sectors that have at least one planet
in them.

Percent of sectors with more than 4 planets in them
This is the percentage of sectors with more than 4 planets in them,
with the maximum being the above percentage.

Minimum distance for home planets
This is the number of sectors away that a home planet must be from
any other home planet. You must keep this in mind for smaller sized
worlds it may be impossible to place a home planet for each of the
races if this value is too large.

Minimum number of nearby planets
This is the number of unclaimed planets that must be near a home
planet for ImpCre to consider that location "fair" to the home
planet.

Maximum distance for those planets
This is how far away the planets may be from the home planet.

Maximum spread of planets
This is the maximum difference between the home planet with the most
nearby planets and the home planet with the least number of nearby
planets. This helps to assure that all planets are placed fairly.

Maximum connect time per day
This is the number of minutes each player may use the game, from
midnight to midnight.

Default starting money
The amount of money that each of the players will have at the start of
the game.

You may also specify the names of each of the races, along with the
name of their home planet. These do nothing except identify the race,
and add some flavor, so feel free to change the names to something
else (red team, etc).

Lastly, you may enter the winner of the last game. If this is the
first game, or you didn't have a conclusive ending to the last game,
you can just leave it blank, or you can make up some non-existant
name. This field should probably be the name(s) of the winning
race(s), but could also be the name(s) of the winning player(s), if
there were just a few that were powerful.