townscaper.js

const { readFile, writeFile } = require('fs/promises');
const { parseStringPromise: parseXML } = require('xml2js');

const maxHeight = 10;
const schema = 'xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"';
const directory = 'c:/Users/denis/AppData/LocalLow/Oskar Stalberg/Townscaper';
const settingsFile = `${directory}/Sett.ings`;
const saveDirectory = `${directory}/Saves`;
const gridFile = `${saveDirectory}/Grid.scape`;
const saveFileName = 'Random.scape';
const saveFile = `${saveDirectory}/${saveFileName}`;

async function run() {
  const grid = await getGrid(gridFile);
  // Choose a set of corners, heights and colours
  const cornerCount = rand(2, 10);
  const heightCount = rand(2, 6);
  const colourCount = rand(1, 15, 2);
  const corners = nOf(cornerCount, () => grid.any());
  const heights = nOf(heightCount, () => rand(0, maxHeight, 2));
  const colours = nOf(colourCount, () => rand(0, 15));
  const spaceCount = cornerCount * heightCount;
  const addCount = rand(4, 10 * spaceCount);

  const cornerHeightColour = new Map();
  nOf(addCount, () => cornerHeightColour.getMap(corners.any()).set(heights.any(), colours.any()));

  const blockCount = cornerHeightColour.totalSize();
  const density = blockCount / spaceCount;
  console.log(cornerCount, 'corners', heightCount, 'heights', colourCount, 'colours',
    addCount, 'blocks', blockCount, 'unique', Math.floor(100 * density), '% occupied');
  await writeFile(settingsFile, settingsText());
  await writeFile(saveFile, saveText(cornerHeightColour));
  console.log(saveFile, 'written');
}

function settingsText() {
  return `<?xml version="1.0" encoding="utf-8"?>
<SettingsData ${schema}>
  <version>1</version>
  <lastSave>${saveFileName}</lastSave>
  <saveIterator>0</saveIterator>
  <currentColor>0</currentColor>
  <audioVolume>255</audioVolume>
  <screenshot><path /><x>1280</x><y>1024</y></screenshot>
</SettingsData>
`;
}

async function getGrid(file) {
  const gridText = await readFile(file);

  return (await parseXML(gridText))
    .SaveData.corners[0].C
    .map((g) => ({ x: parseInt(g.x[0], 10), y: parseInt(g.y[0], 10) }));
}

function saveText(cornerHeightColour) {
  const cornerXmls = [];
  const voxelXmls = [];

  cornerHeightColour.forEach((heightColour, corner) => {
    cornerXmls.push(cornerXml(corner, heightColour.size));
    heightColour.forEach((colour, height) => voxelXmls.push(voxelXml(colour, height)));
  });

  const cornersXml = `\n${cornerXmls.join('')}  `;
  const voxelsXml = `\n${voxelXmls.join('')}  `;

  return `<?xml version="1.0" encoding="utf-8"?>
<SaveData ${schema}>
<cam><x>80</x><y>200</y><z>200</z>
</cam>
<corners>${cornersXml}</corners>
<voxels>${voxelsXml}</voxels>
</SaveData>
`;
}

function cornerXml({ x, y }, count) {
  return `    <C><x>${x}</x><y>${y}</y><count>${count}</count></C>\n`;
}

function voxelXml(colour, height) { return `    <V><t>${colour}</t><h>${height}</h></V>\n`; }

function rand(min, max, power = 1) {
  return Math.floor(min + (max - min + 1) * Math.random() ** power);
}

function nOf(n, f) {
  const result = [];
  while (n-- > 0) result.push(f());
  return result;
}

Array.prototype.any = function any(power = 1) { return this[rand(0, this.length - 1, power)]; };

Array.prototype.sum = function sum() { return this.reduce((a, b) => a + b, 0); };

// Map of Maps

Map.prototype.getMap = function getMap(key) {
  let m = this.get(key);
  if (!m) this.set(key, m = new Map());
  return m;
};

Map.prototype.totalSize = function totalSize() {
  return [...this.values()].map((m) => m.size).sum();
};

run();