Factorio: Restore Crash Site

factorio-restore-crash-site.lua

/silent-command
--[[
  This is Factorio code from data/core/lualib/crash-site.lua, with unnecessary parts removed,
  especially the fires and explosions which were many lines of code.
  It is Wube code and subject to their EULA, and they can DMCA it, but they generally don't care
  about their script being reused in mods and player script.

  If the crash site area is cluttered, it will displace the crash parts into places that fit, which may look weird.
  So it's best to clear the area before using it.
  It could of course be modified to clear things itself, but I didn't try.
]]

local crash_site_location = {-5, -6}

local default_ship_parts = {
  {
    name = "crash-site-spaceship-wreck-big-1",
    angle_deviation = 0.1,
    max_distance = 25,
    min_separation = 2,
  },
  {
    name = "crash-site-spaceship-wreck-big-2",
    angle_deviation = 0.1,
    max_distance = 25,
    min_separation = 2,
  },
  {
    name = "crash-site-spaceship-wreck-medium",
    variations = 3,
    angle_deviation = 0.05,
    max_distance = 30,
    min_separation = 1,
  },
  {
    name = "crash-site-spaceship-wreck-small",
    variations = 6,
    angle_deviation = 0.05,
    min_separation = 1,
  }
}

local rotate = function(offset, angle)
  local x = offset[1]
  local y = offset[2]
  local rotated_x = x * math.cos(angle) - y * math.sin(angle)
  local rotated_y = x * math.sin(angle) + y * math.cos(angle)
  return {rotated_x, rotated_y}
end

local entry_angle = 0.70
local random = math.random
local get_offset = function(part)
  local angle = entry_angle + ((random() - 0.5) * part.angle_deviation)
  angle = angle - 0.25
  angle = angle * math.pi * 2
  local distance = 8 + (random() * (part.max_distance or 40))
  local offset = rotate({distance, 0}, angle)
  return offset
end

local get_name = function(part, k)
  if not part.variations then return part.name end
  local variant = k or random(part.variations)
  return part.name.."-"..variant
end

local function create_crash_site(surface, position)
  local main_ship = surface.create_entity
  {
    name = "crash-site-spaceship",
    position = position,
    force = "player",
    create_build_effect_smoke = false
  }
  local box = main_ship.bounding_box
  for k, entity in pairs (surface.find_entities_filtered{area = box, force = "neutral", collision_mask = "player"}) do
    if entity.valid then
      if entity.type == "tree" then
        entity.die()
      else
        entity.destroy()
      end
    end
  end

  for k, part in pairs(default_ship_parts) do
    for k = 1, (part.variations or 1) do
      local name = get_name(part, k)
      for i = 1, part.repeat_count or 1 do
        local part_position
        local count = 0
        local offset
        while true do
          offset = get_offset(part)
          local x = (position[1] or position.x) + offset[1]
          local y = (position[2] or position.y) + offset[2]
          part_position = {x, y}

          local can_place = surface.can_place_entity
          {
            name = name,
            position = part_position,
            force = "player",
            build_check_type = defines.build_check_type.manual_ghost,
            forced = true
          }

          if can_place then
            if not part.min_separation or surface.count_entities_filtered{position = part_position, radius = part.min_separation, limit = 1, type = "tree", invert = true} == 0 then
              break
            end
          end

          count = count + 1
          if count > 20 then
            part_position = surface.find_non_colliding_position(name, part_position, 50, 4)
            break
          end
        end

        if part_position then
          local entity = surface.create_entity
          {
            name = name,
            position = part_position,
            force = part.force or "neutral",
            create_build_effect_smoke = false
          }

          for k, entity in pairs (surface.find_entities_filtered{type = {"tree", "simple-entity"}, position = part_position, radius = 1 + entity.get_radius()}) do
            if entity.type == "tree" then
              entity.die()
            else
              entity.destroy()
            end
          end
        end

      end
    end
  end

end

create_crash_site(game.get_surface("nauvis"), crash_site_location)