I wrote this tutorial a while back, and tested it with a few users. Seemed to work well, and I've never seen another one like it.
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Preset Field Values Tutorial, 2012-06-04, by VjekUse this worldgen for this tutorial.
[WORLD_GEN]
[TITLE:PFV_TESTING1]
[DIM:33:33]
[EMBARK_POINTS:2500]
[END_YEAR:300]
[BEAST_END_YEAR:350:99]
[REVEAL_ALL_HISTORY:0]
[CULL_HISTORICAL_FIGURES:1]
[ELEVATION:100:360:0:0]
[RAINFALL:10:100:0:0]
[TEMPERATURE:-36:85:0:0]
[DRAINAGE:10:100:0:0]
[VOLCANISM:0:100:0:0]
[SAVAGERY:0:100:0:0]
[ELEVATION_FREQUENCY:1:1:1:1:1:1]
[RAIN_FREQUENCY:1:1:1:1:1:1]
[DRAINAGE_FREQUENCY:1:1:1:1:1:1]
[TEMPERATURE_FREQUENCY:1:1:1:1:1:1]
[SAVAGERY_FREQUENCY:1:1:1:1:1:1]
[VOLCANISM_FREQUENCY:1:1:1:1:1:1]
[MINERAL_SCARCITY:1000]
[MEGABEAST_CAP:0]
[SEMIMEGABEAST_CAP:0]
[TITAN_NUMBER:0]
[TITAN_ATTACK_TRIGGER:0:0:0]
[DEMON_NUMBER:0]
[NIGHT_TROLL_NUMBER:0]
[BOGEYMAN_NUMBER:0]
[VAMPIRE_NUMBER:0]
[WEREBEAST_NUMBER:0]
[SECRET_NUMBER:0]
[REGIONAL_INTERACTION_NUMBER:0]
[DISTURBANCE_INTERACTION_NUMBER:0]
[EVIL_CLOUD_NUMBER:0]
[EVIL_RAIN_NUMBER:0]
[GOOD_SQ_COUNTS:0:0:0]
[EVIL_SQ_COUNTS:0:0:0]
[PEAK_NUMBER_MIN:0]
[PARTIAL_OCEAN_EDGE_MIN:0]
[COMPLETE_OCEAN_EDGE_MIN:0]
[VOLCANO_MIN:0]
[REGION_COUNTS:SWAMP:0:0:0]
[REGION_COUNTS:DESERT:0:0:0]
[REGION_COUNTS:FOREST:0:0:0]
[REGION_COUNTS:MOUNTAINS:0:0:0]
[REGION_COUNTS:OCEAN:0:0:0]
[REGION_COUNTS:GLACIER:0:0:0]
[REGION_COUNTS:TUNDRA:0:0:0]
[REGION_COUNTS:GRASSLAND:0:0:0]
[REGION_COUNTS:HILLS:0:0:0]
[EROSION_CYCLE_COUNT:0]
[RIVER_MINS:0:0]
[PERIODICALLY_ERODE_EXTREMES:0]
[OROGRAPHIC_PRECIPITATION:0]
[SUBREGION_MAX:1500]
[CAVERN_LAYER_COUNT:1]
[CAVERN_LAYER_OPENNESS_MIN:1]
[CAVERN_LAYER_OPENNESS_MAX:2]
[CAVERN_LAYER_PASSAGE_DENSITY_MIN:0]
[CAVERN_LAYER_PASSAGE_DENSITY_MAX:0]
[CAVERN_LAYER_WATER_MIN:10]
[CAVERN_LAYER_WATER_MAX:15]
[HAVE_BOTTOM_LAYER_1:1]
[HAVE_BOTTOM_LAYER_2:0]
[LEVELS_ABOVE_GROUND:1]
[LEVELS_ABOVE_LAYER_1:40]
[LEVELS_ABOVE_LAYER_2:2]
[LEVELS_ABOVE_LAYER_3:2]
[LEVELS_ABOVE_LAYER_4:2]
[LEVELS_ABOVE_LAYER_5:2]
[LEVELS_AT_BOTTOM:2]
[CAVE_MIN_SIZE:1]
[CAVE_MAX_SIZE:1]
[MOUNTAIN_CAVE_MIN:0]
[NON_MOUNTAIN_CAVE_MIN:0]
[ALL_CAVES_VISIBLE:1]
[SHOW_EMBARK_TUNNEL:2]
[TOTAL_CIV_NUMBER:5]
[TOTAL_CIV_POPULATION:0]
[SITE_CAP:0]
[PLAYABLE_CIVILIZATION_REQUIRED:1]
[ELEVATION_RANGES:0:0:0]
[RAIN_RANGES:0:0:0]
[DRAINAGE_RANGES:0:0:0]
[SAVAGERY_RANGES:0:0:0]
[VOLCANISM_RANGES:0:0:0]
To bring up the Preset Field Values (PFV) interface, from the Main Menu, select: Design New World with Advanced Parameters, then move the selection to the worldgen you pasted into \init\worldgen.txt, then choose e to edit, and p for "set Preset Field Values"
You'll be presented with a box on the left, and some geographical aspects on the right:
ELEV = Elevation. This is how high the land is. 0-99 is ocean. 100-299 is a variety of landscapes. 300-400 is mountain.
RAIN = Rain! How much rain will this area get. Yes, you can control exactly which region tiles get rain. Deserts next to swamps, if you want.
TEMP = Temperature. You can designate areas to be freezing or scorching, as you wish.
DRAIN = Drainage. Again, badlands next to swamps, or forests next to grasslands.
SAV = Savagery. Lets you control if your mountains are calm, and the rest of the world is 100% savage. Or have savage plains, but calm forests.
VOLC = Volcanism. You can paint where you want volcanoes and/or igneous extrusive layers to be generated. In general, if a volcano breaks the surface, it will significantly alter the elevation in an area, so you've been warned.
If you left-click on (View) for any of the geographical aspects, it will presume you wish to modify them, and switch to "Will be saved" if you had previously changed it to "Randomize at gen"
If you left-click on "Randomize at gen" or "Will be saved" it will toggle between them
If you left-click on the Brush Radius number, it will let you type in a new number.
If you left-click on the word "Normal Brush" it will toggle between "Normal Brush" and "Smoothing Brush"
If you press enter, wherever the mouse cursor is will be updated to show all the geographical aspects on that spot, and will "render" the world to give you a rough idea of how things will look.
If you left-click on the word "Painting" it will toggle between "Painting" and "No painting".
Right click pans the working area - however, it's reversed. If you right click at the bottom, it will pan up. If you right click at the top, it will pan down. Right clicking closer to an edge will make the pan jump farther. If you right click closer to the center, it will pan in very small increments. 0x0 is the upper left, 32x32 (in this sized map) is the lower right.
To start out, you want to see Not Painting and Randomize at Gen for all aspects (ELEV, RAIN, TEMP, DRAIN, SAV, VOLC)
Why? This is what a "normal" worldgen would look like. Each aspect is randomized, and there are no manual adjustments to begin with. Once you've set every Painting to Not Painting, and every "Will be saved" to "randomize at gen" you're ready to start. (12 clicks!)
So, lets do something simple. Left click once on (View) next to ELEV. We see the brush is set to some value like 200/125. We want to set that to something different, to make all the world a flat low elevation, to start. click on the light blue Brush word under ELEV. Now you can type a value. Type in 0 and see what happens. It should change to 100/100. This means our minimum value is elevation 100, which it was, in the worldgen settings. We tried to set it to zero, and it adjusted it to the lowest possible value, which is 100.
Now left click in the upper left corner of the painting area. Nothing happened, right? Nothing should have happened, because "Not painting" was selected. Toggle that back to "painting" under ELEV and try again. You'll see a single tile changed color (to a darker green). This indicates the elevation here is different. We could change the entire map one tile at a time, but that's tedious. Let's enlarge the brush and try again. Click on "Brush Radius" and put in 8. Now left click in the upper left corner again. You'll see a much larger area has been changed. left click all over until everything is covered in the 100 elevation paint.
You haven't done the whole map! You think you have, but you haven't. You need to pan the map down to see the rest. Do this by right clicking in the upper half of the painting area. You'll see there's some unpainted elevation down south there. paint all that. Ensure you're at the bottom by left clicking on the bottom right, and noting it is 32x32. Now pan back up by right clicking in the bottom half of the painting area until the upper left corner is 0x0.
Now, lets paint some mountains! Left click again on the light blue Brush word under ELEV. Type in 400. You'll note the elevation value changes to 360/210. Again, 360 was our maximum in the worldgen parameters, so it's the highest we can paint. Ensure the brush is set to "painting" for ELEV and left click once in the middle of the map. You'll see the elevation change reflected in a a different color and symbol.
That's enough for now, press escape twice, and F6 to save. Now try generating a world and see if it looks as you would expect (mountains in the middle!)
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I wasn't sure where would be a good spot to start with this, but the plan was: If this one worked for enough people, to write a second one that would continue on and describe how to make a forest in the middle of some grassland by modifying rain and drainage both. Then solicit feedback and continue on from there.