Just for fun, a dotfile to help plan a train-based Factorio base

production-traffic.gv

digraph {
  rankdir=LR;

  { iron_ore copper_ore stone coal uranium_ore } -> ore_line
  
  // smelter: specific to iron/copper plate production (1:1 ratio)
  // quarry: any stone or pure stone-based production
  // steel mill: specific for steel plate production
  //     due to 5:1 ratio, iron ore fed separate from general smelter
  
  // processor: centrifuges for uranium processing and enrichment

  // train depot: production of trains and their infrastructure
  
  processor -> ore_line
  ore_line -> {
    quarry
    smelter
    steel_mill
    plant
    processor
    train_depot
    armory
  }

  // water proximity preference
  { rank=same; quarry refinery plant power }
  water -> { quarry refinery plant power }

  // there are three basic train traffic patterns
  
  // ore-liquid line: raw materials from world into the base
  // plate-liquid-fuel line: products made directly from raw materials
  // parts-product line: some assembly required

  { rank=same; liquid_line plate_line fuel_line }
  { rank=same; parts_line product_line }

  refinery -> liquid_line
  crude_oil -> liquid_line
  liquid_line -> {
    refinery
    electronics
    engines
    infrastructure
  }

  // plant: chemical plant production not purely from raw refinery liquid
  plant -> { plate_line ore_line liquid_line fuel_line }

  // solid/rocket/nuclear fuel for rocket, trains and backup steam power
  fuel_line -> {
    power
    train_depot
    rockets
  }

  // components: basically, solely composed from plate products
  //   wire, stick, gear, pipe, barrel, low density structure

  { smelter steel_mill } -> plate_line
  // plate line destinations
  plate_line -> {
      armory
      science
      plant
      components
      electronics
      infrastructure
      engines
      robotics
      train_depot
  }

  components -> parts_line
  electronics -> parts_line
  engines -> parts_line
  robotics -> parts_line
  armory -> product_line
  quarry -> product_line
  infrastructure -> product_line

  parts_line -> {
    infrastructure
    science
    train_depot
    engines
    robotics
  }

  product_line -> {
    science
    electronics
    robotics
    rockets
    infrastructure
    train_depot
  }

  // there could be a "science line"
  // science production lends itself better to co-locate with the lab

  science -> lab
}