Editing Advanced world generation

{{Quality|Exceptional|18:16, 23 August 2014 (UTC)}}

:''This article contains information on advanced world generation. For information on basic world generation, see [[World generation]].''

:''See [[World token]] to more easily find information by the names used in the world_gen.txt file, [[World rejection]] for information on solving problems related to worlds always being rejected, and [[Worldgen examples]] for example worlds.''

When you want more control of what your world looks like, it's time for '''advanced world generation''': A detailed reference with advice is provided below. (This article assumes that you are already familiar with [[World generation|'''basic world generation''']]. If you are not, then please read about that first - the very high amount of extra options for a generated world can provide the player with a much more customized experience.)

 

Once you select {{DFtext|Design New World With Advanced Parameters}} from the main menu, a screen that looks something like this will appear:

 

[[File:AdvancedWorldGen.png‎]]

 

This screen is relatively intuitive, but some parts could use explanation.

The list of already-defined parameter sets is in the upper-right corner. You can select the current set that you want to work with using the up and down directional keys.

 

Parameter sets are stored in the <tt>data/init/world_gen.txt</tt> file in the main DF directory. The {{K|F1}} and {{K|F6}} keys will load and save '''all''' of the parameter sets to this file. You will need to save the world gen parameters to this file before you hit {{K|Enter}} to generate the world.

 

The <tt>world_gen.txt</tt> file can also be edited with a text editor. This is particularly useful because people will often post their parameter sets on the forum or wiki in text form. (See below for more info.) The {{K|F1}} key comes in handy when editing this file while the game is still running.

 

To get the parameters used to generate a world you are already playing, press {{K|ESC}} then choose export images; exporting any image will also create the world generation parameter file, for more information see this [http://www.bay12forums.com/smf/index.php?topic=101280.msg4512541#msg4512541 post].  

As previously mentioned, the title of the parameter set doesn't affect the name of the world. You can force a particular name for your world using {{K|n}} or set it back to the default random setting using {{K|N}}.

The size of the map to be generated can be selected with {{K|u}} {{K|i}} {{K|o}} {{K|p}}. Larger maps take longer to generate and may limit [[Frames per second|FPS]] in-game.

 

Changing the dimensions of the world will reset the parameters because many of them have different defaults depending on the surface area available.

Creating larger worlds does not necessarily mean longer world generation time. The essential factor for the gen duration is the history. If you restrict the number of historical events, you can significantly speed up the process.

| Valid values are 17, 33, 65, 129, and 257. Others may not work.

A specific seed value can be entered with {{K|s}}. This will change '''all''' of the seed values to the value you enter. If you need to enter different seed values for each type of seed, use {{K|e}}.

 

In order to find out what seed values were used for the last world you generated, you can look at this screen. If you want to be able to tell someone else how to generate exactly the same world that you just generated, they will need all of the seed values listed under Last Param Set.

When generating a world using a seed, the way that the world is generated is also based at least in part on certain world tokens. As such, you cannot, for example, change the minimum and maximum rainfall and get the same world but drier or wetter, instead, a different world is generated. That said, it would also seem that certain small changes to these world tokens can occasionally generate a very similar world, however, other tokens are more sensitive. For more information see the forum thread [http://www.bay12forums.com/smf/index.php?topic=112132.msg3404199#msg3404199 here].

The following are tokens which appear to be involved in the implementation of the seed and are not safe to change:

Many other world parameters such as end year and embark points can, however, be changed without it having any effect on the geography of the world generated from the seed values.

Normally you don't enter these seed values and the world generation process comes up with seed values based on some sort of "true" random information from things like random values in uninitialized memory, the current date/time, etc. If you have entered a seed value you can revert to all seeds being random using {{K|S}}.

Unless you're using an already-defined parameter set, you will probably want to {{K|e}}dit the parameters. Select the set you want to edit using the up/down directional keys and press {{K|e}}. Information about each parameter is documented below.

 

Once you are happy with the parameters you have set, hit {{K|Esc}} to get back to this screen, hit {{K|F6}} to save the values you just edited, and hit {{K|Enter}} to start. The rest of the process is the same as basic [[world generation]].

Parameter sets are stored in the ''data/init/[[world_gen.txt]]'' file, using [[world token]]s. You can copy and paste other players' sets of parameters into your ''world_gen.txt'' to use their parameter sets, and some are provided at [[Main:Pregenerated worlds|Pregenerated worlds]]. Another place to find parameter sets is the [http://www.bay12forums.com/smf/index.php?topic=101280.0 Worldgen cookbook] thread on the official forums.

'''Terrain Parameters''': as described below, these 5 variables define the basic background world, how hot or cold it is, how much rainfall, how high the mountains are. The world automatically goes through the temperature range along the Y axis although sometimes it will be hotter in the north, other times in the south. Minimum, maximum and X,Y variance can drastically alter the world.  

'''Rejection Parameters''': ''Dwarf Fortress'' has a belt-and-braces approach to world generation. The above controls allow you to shape the world, then the rejection parameters throw it out if it isn't right! There are a number of rejection parameters for the number and degree of the 5 basic variables, for biome types etc. If the world does not meet the requirements of any one rejection parameter the world is rejected and re-randomised. Also see [http://dwarffortresswiki.org/index.php/DF2012:World_rejection World Rejection]

Here you can enter specific seed values for different parts of the world generation process. Different sequences of pseudorandom numbers are used for different parts, so you can use this to reproduce only the particular part of world generation from some previously generated world if you want.

This controls the number of points that you have for skills and equipment when you embark in fortress mode. Turning this value up will allow games started in this world to start with more skilled dwarves with better equipment. Normally you can do just fine by leaving this value set to default, but you might want to up it for experimental/testing purposes or to help dwarves survive in a particularly evil world. The highest amount this value can be set to is 10000.

This is how many years of history are generated for the world. This is basically the same as the History parameter in basic world gen, except that you can enter an exact value for number of years. See [[World_generation#History|History]] for more info.

This controls the maximum number of towns and similar sites on the entire map. Raising the number will allow for more towns, etc. though the number of sites will ultimately still be limited by things like space, terrain, and population cap.  

 

Note that this parameter controls only '''"civilization" sites''' like towns - other sites, such as lairs, will be added on to this maximum.  After civilizations reach this cap, they will not spread out any more to place new cities.

By default, the raws limit each civilization site to a population of 120 regardless of the race of the civilization. Therefore, without editing the raws, the total population on the map can't go above site cap x 120.

Beware, increasing this too high can slow worldgen down by a lot. Another effect can be goblins (or other civs) sometimes overwhelming all other civs and/or flooding the world with their homes, leaving no good places to build your fortress, be it human or dwarven. If you choose a low cap to hasten world generation, the cap will likely be reached within years, stopping expansion of all civs. If you want a good and long history you will have to adjust site/population cap and the number of civs many times to find one fulfilling your needs.

The world starts out with a certain number of powerful megabeast and titan entities in existence. If a percentage of the megabeast and titan population dies out during history generation, then history generation will stop early. For example, if the elimination value is 80%, and the generated history starts with 200 entities and 160 of those 200 entities are eliminated by historical events before the End Year is reached, history generation will stop early.

Whether or not the game ignores unimportant figures in history generation. The culling is many CPU-intensive steps in history generation but it saves memory and will speed up loading/saving games a bit. This does mean that the "unimportant" figures will not appear in Legends mode or in things like dwarf engravings, but they might not appear in engravings anyway.

Unimportant figures are creatures who suffer early deaths, never having offspring or killing anything named during history generation. For example, residents of goblin towers may get murdered by demons at a young age. After culling unimportant figures, Legends mode would say something like the demon has killed "an unknown creature at Eviltower in the year 102."

Setting this to Yes will allow access to all information about the history of the world in Legends mode. If set to No, then you will have to discover historical information in adventure mode or by instructing dwarves to make engravings.{{Verify}}

These are the absolute minimum and maximum values that can ever be generated for a particular map square characteristic. Changing these can cause the occurrence of certain [[Biome|biomes]] to become impossible, so modify these with care. Because of this problem, you may want to use [[#Weighted Ranges|Weighted Ranges]] instead.

 

By ''subtly'' tweaking the min and max values, vastly different maps can be made.

 

 

 

 

For "patchwork" worlds to avoid being rejected, [[#Maximum_Number_of_Subregions|Maximum Number of Subregions]] will probably need to be increased from the default.

* River start locations need a minimum elevation of 300. Therefore, a world with a maximum elevation of 299 everywhere prevents river generation, but rivers can still occur if maximum elevation is set to 300.

*Mountain peaks can only form in squares with an elevation of 400.

Controls the amount of rainfall in each map square/area. Setting the minimum too high or the maximum too low can make the formation of certain biomes impossible. Rainfall causes it to [[rain]] more in a given area, which can have various effects.

Also makes more rivers appear on the world map.

Note that if [[#Do Orographic Precipitation and Rain Shadows|orographic precipitation and rain shadows]] is on then mountains will cause additional variance in rainfall, so (for example) rainfall below the specified minimum can occur in the shadow of a mountain.  If you want the minimum and maximum for this parameter to be absolutely respected you must turn off the orographic precipitation option.

These parameters form the "base" temperature for an area, and describe peak summer temperature in degrees Celsius. This does not correspond 1:1 with the final climate. [[Temperature]] is always influenced by a number of variables, including elevation, time of year, thick forestation, and if [[Advanced_world_generation#Poles|Poles]] are enabled, latitude. These other variables are factored in after the temperature mesh is applied, and frequently bring temperatures above and below their set minimum and maximum values. The inclusion of Poles is particularly strong in this regard, as it allows latitude to raise and/or lower temperatures by more than 75 degrees Celsius! That said, the temperatures aren't raised or lowered by more than about 65 degrees past the set minimum and maximum. Furthermore, for typical ranges the temperature will never be raised more than about 25 degrees past the maximum (but will still drop up to about 65 degrees Celsius below the minimum).

Lower drainage values have been reported to contribute to the formation of thicker soil layers though it is currently unknown exactly how other factors (such as elevation or perhaps rain) impact soil formation.

Volcanism controls the occurrence of igneous [[Layer|Layers]], and the formation of volcanoes. For a volcano to form, a square must have a volcanism value of 100 so reducing the maximum from 100 will make volcanoes impossible. Raising the minimum will increase the rarity of non-igneous layers.

Setting the minimum to a high value is not a good way to produce multiple volcanoes, as you are likely to get a "Volcanism not evenly distributed" rejection. Instead use the Minimum Number of Volcanoes parameter and possibly adjust the weighted ranges for volcanism as described below.

These parameters control the level of [[Surroundings#Savage|savagery]] on the map. Raising the minimum savagery too high may make it impossible for certain races to exist, and similarly lowering the maximum too far can make it impossible for certain creatures to exist. The largest chance of having unusable maps comes from too high of a savagery value.

These parameters make it possible to influence the number of squares in a particular range without making conditions outside of that range impossible. For example, you can make it possible for many more low elevation squares to exist without making it impossible for high elevations to form. Changing these parameters is often preferable to simply changing the min/max values.

# Set the intersection points of the grid lines to a random value according to the weighted ranges.

Where ''MeshSize'' is the raw parameter value found in the world_gen.txt. See the image on the right for an example.

[[File:World_map-large-32x32-elevation-mesh.png|thumb|300px|A large world generated with an Elevation Mesh Size of 32x32 and range weights set to 1:0:0:0:1 (i.e., only extreme high and low elevations). Note how the grid intersections are either set very high or very low and the space between them is smoothed out.]]

==== Mesh Size ====

Mesh size determines how many grid tiles there will be. Setting this to Ignore will cause the weighted range settings to be ignored for that terrain characteristic. As an example, setting it to 2x2 means the grid will be 2 times 2 tiles large and there will be 3 times 3 for a total of 9 intersection points. On a pocket world this means one grid tile will be 8 * 8 world tiles large whereas on a large world one grid tile will be 128 * 128 world tiles. Note that the highest possible value for a given world size will always make the grid tiles 8 * 8 world tiles large.

The end result can vary greatly depending on how the corresponding [[#X_and_Y_Variance|X and Y Variance]] parameters are set. First of all, if the variance is too large the noise it adds can completely negate the effect of the weighted ranges. For instance, with a 2x2 mesh, the default variance parameters are high enough that usually the mesh grid can hardly be recognized. How strong the variance's effect is, is also dependent on the mesh size. Having a larger mesh size (i.e. smaller grid tiles) means the variance also has to be higher for a visible effect. For instance, with a variance of 400, the effects are clearly visible with a 2x2 mesh and barely visible at all with a 8x8 mesh. Note that this effect is directly dependent on the mesh size and not, as one might expect, on the actual size of the grid tiles. This means, that a large world with a 2x2 mesh will look essentially the same as a pocket world with a 2x2 mesh, only stretched to 256 times the size.

This will cause the world to be rejected if fewer than this many peaks (based on elevation) are present on the map. Elevations of 400 must be possible for mountain peaks to occur. If set to zero then worlds will not be rejected based on number of peaks.

You may need to adjust elevation parameters, such as the highest weighted range, in order to get the desired number of elevation-400 squares needed for larger numbers of peaks. Like volcanoes, mountain peaks can make embark zones more interesting, but other than that, they don't appear to "do" anything special. Reportedly they do increase the highest Z-level above ground in all embark zones in the same region even if the selected embark zone does not include the peak.

Note that the ability for this many edge oceans to exist will be limited by elevation. Therefore, to actually create large oceans you will probably need to change things like the Elevation Mesh Size and Weighted Ranges to increase the number and distribution of very low elevation squares on the map.

*2 results in another coastline along with the first one.  The map could end up looking something like Panama if the oceans pick opposite sides of the map.

Unfortunately there's no easy way to control which oceans end up on which edges, except perhaps setting X and Y variance to different values.

This is the number of megabeasts placed at the beginning of history. Megabeasts are [[hydra]]s, [[bronze colossus]]es, [[roc]]s, and [[dragon]]s, which are all placed in equal proportions [http://www.bay12forums.com/smf/index.php?topic=112465.msg3415177#msg3415177 ^data].  

This is the number of semi-megabeasts placed at the beginning of history. Semi-megabeasts are [[giant]]s, [[ettin]]s, [[minotaur]]s, and [[cyclops]], which are placed in equal proportions [http://www.bay12forums.com/smf/index.php?topic=112465.msg3415188#msg3415188 ^data].

[[Titan]]s will begin to attack your fort once at least this many dwarves inhabit it, regardless of whether any other attack criteria have been met. This number defaults to 80 which isn't usually too difficult to deal with.

Titans will begin to attack your fort once you have exported at least this many [[Currency|dwarfbucks]] worth of merchandise, regardless of whether or not any other criteria have been met. This parameter defaults to None (disabled).

[[Demon|Demons]] are similar to titans and forgotten beasts in that they are procedurally generated, but, unlike titans, they are not unique. Thus, many different types of demons will exist in the world, but there will be many members of each type. Setting this to zero means no demons will exist, limiting the amount of fun you can have. Thanks to [[Underworld spire|certain fun things]], fewer demon types also means fewer goblin civilizations[http://www.bay12forums.com/smf/index.php?PHPSESSID=7348f68f41a9659443c05b2acf534e6c&topic=112465.15].You need at least 2 demon types, or goblin civilizations won't exist.

 

The number of different [[Bogeyman|bogeyman]] forms that will exist in the world. Bogeymen are procedurally generated, though their forms do not vary by much. Setting this to zero means that the world will have no bogeymen, custom or otherwise.

==== Number ====

Werebeasts will begin to attack your fort once you have exported at least this many [[Currency|dwarfbucks]] worth of merchandise, regardless of whether or not any other criteria have been met. This parameter defaults to 5000.

The number of secrets that exist in the world. Currently, all secrets are secrets of life and death, and the ones holding these secrets are necromancers, thus setting this to zero means that no [[necromancer]]s will appear.

| <tt><nowiki>[SECRET_NUMBER:44]</nowiki></tt>

=== Number of Evil Cloud Types ===

 

The lesser of a relatively large group of evils... evil rain. This number states how many different types of green-ooze drenchers, disconcerting blood-showers, and sickly yellow slime-baths can occur in your world. Compared to evil clouds though, this one hardly is worth stressing out about, usually.... Setting this to zero means the only semi-solid to fully-liquid fluids to fall from the sky will be pure H2O.  

 

This turns the generation of [[Divine_metal|divine metals]] on or off. It does not influence the creation of vaults.

=== Desired Good/Evil Square Counts ===

These values change the amount of [[Surroundings#Good|good or evil]] tiles on the map, depending on the size of the region they are being considered for. The counts are for all tiles in all subregions of a given size considered together, ''not'' counts for each subregion considered separately. (all tiles in the same subregion share the same [[Surroundings|surroundings]] values.)

The counts used here will always be restricted to regions of the given size no matter how large the count. Also, the count is more of a goal than a minimum or maximum. As a result, you can end up with many more or many fewer than the requested number of squares in some situations.

In particular, if you have something like a case where only 3 large regions exist in a world, and you request "1 evil square" in large regions, you will end up with one of the large regions being ''entirely evil''.  So any non-zero value in one of these settings essentially means "force at least one region of this size to be all good/evil."

Note that the "evilness" of evil biomes is also impacted by savagery.

Certain civilizations cannot exist in good and/or evil squares, so too many of one or the other may limit the size of certain types of civilizations.  Dwarves, for example, need non-aligned biomes.  Creating too many evil biomes seems to lead to the danger of an early extinction of many civilizations.

0 means no minimum for rejection. Setting to 0 does not guarantee 0 squares of that biome.

This is the minimum number of squares of the given biome that must exist before things like erosion take place.

One thing to keep in mind is the maximum number of squares on a map of a given size. If the total number of squares on a map is lower than the sum of all square count parameters then you will get infinite world rejection.

Tells the world-generator how long the world has to erode its tall peaks down to mountainsides during the 'running rivers...' stage of world creation. The higher this number, the less jagged the world will be, and the more wide the major rivers will be. If you use the maximum number, your mountains will dissolve before your eyes into plains which can lead to rejections if there aren't enough mountains to use for river start points and dwarven civilization origin points.  

Toggle that allows terrain height to affect rainfall. For example, moist air coming from the ocean blows over the land. As the terrain gets higher, it forces the moist air up, causing it to rain on the seaward side of a mountain. Eventually, all the rain has fallen if the mountain is tall enough. So, when the breeze goes over the top, there's no moisture left to fall on the other side, creating a rain-shadow. In the current version, regions where drainage is above 50 will also create rain shadows, regardless of the underlying biome and elevation.{{cite forum|140685/5484064}} The rain shadows will always be created as if the wind is blowing from west to east.

[[Caverns]] are the hollow areas underground which dwarves tend to encounter when they're digging around.

This parameter determines how many cavern systems will be generated, not including the magma layer or the Bottom layer.  Defaults to three. Setting it to lower values could help FPS.

*Disabling caverns by setting this to 0 will make it impossible to grow any underground plants, as none will exist for your civilization to cultivate. (Underground plants will not be available on embark.)

This determines how many passages form the cavern. If openness (see above) is set to minimum and density increased then you will get a maze like network of small criss-crossing passages. Raising the values further increases the number of the maze-like passages.

Determines how many caverns will have water at the bottom.  Note that, even at 100, there will be some amount of ground in caverns, but each cavern 'bubble' will contain some amount of water.

Setting 1/Yes causes the magma layer to exist, value 0/No prevents it. Appears not to have impact on volcanoes, nor volcanism, so even if 0/No there will still be embark locations with magma. If a [[volcano]] exists, it appears to always tap the magma sea, but the magma sea will not be revealed by revealing the volcano.

The following table assumes that you have 3 cavern layers.  The Levels Above Layer settings control how many Z-Levels are above each layer.  A layer may itself consist of multiple Z-Levels (and almost always does).

|style="border:1px #AAA solid;padding:0.2em;"| Z-levels of earth between very top of second cavern and very bottom of first cavern.

|style="border:1px #AAA solid;padding:0.2em;"| Z-levels of earth between very top of third cavern and very bottom of second cavern.

|style="border:1px #AAA solid;padding:0.2em;"| Z-levels of earth between very highest magma and very bottom of third cavern.<br />Spoiler Hidden (select invisible text to read): <span style='color:#eee;'>Making this high will give a large area for HFS veins, so that it never touches caverns, giving more to mine '''if''' it was impacting the cavern previously.</span>

|style="border:1px #AAA solid;padding:0.2em;"| Appears to be number of levels of HFS chamber.<br />Only valid if Bottom Layer present.<br />Often has no impact.<br />Values larger than default result in strange things.

Caves are sort of like caverns, except that they have a passage to the surface, and are generally much smaller. Caves can connect to caverns if they are sufficiently deep.

==== Number of (Non-)Mountain Caves ====

The number of caves that will be generated. Lurking [[kobold]]s set up shop in caves, and store their stolen items there - a setting of 0 in both will stop kobold civilizations from appearing.  Special note: a cave is not a [[lair]].   

If set to no (default) then the location of caves will not be marked on the map. If set to yes, caves will appear on the map as {{Raw Tile|•|#808080|#00DD00}} symbols so that they may be sought out or avoided as desired.

This parameter doesn't do anything.

Sets the minimum possible number of squares of certain ranges of each of the region qualities, such as elevation, rain, drainage, volcanism, savagery, and temperature. These need to be changed to reflect your regional meshes and weights. These are responsible for a HUGE number of map rejections. These values can all be set to 0 for much fewer map rejections, particularly in the case of more wacky, non-standard maps.  

:''Main article [[World rejection]]''

If you are having the common problem of your generated worlds always being rejected by the world generator, see [[v0.31:World rejection|Solving World Rejection Problems (v0.31 page)]] as it contains many detailed suggestions on how to troubleshoot and solve these issues.

If you're trying to do something specific then the [[Worldgen examples]] might be helpful. These are complete parameter sets that can be copied directly into your ''world_gen.txt'' file and customized as desired.