make-heightmap.ts

import fs from 'fs';
import path from 'path';
import sharp from 'sharp';

function addPngExtension(path: string) {
  return path.split(".").at(0) + ".png";
}

function ensureDir(dirPath: string): Promise<void> {
  return new Promise((resolve, reject) => {
    const fullPath = path.resolve(dirPath);

    fs.stat(fullPath, (err, stats) => {
      if (err && err.code === 'ENOENT') {
        fs.mkdir(fullPath, { recursive: true }, (mkdirErr) => {
          if (mkdirErr) {
            reject(mkdirErr);
          } else {
            resolve();
          }
        });
      } else if (stats && stats.isDirectory()) {
        resolve();
      } else {
        reject(new Error(`${fullPath} is not a directory`));
      }
    });
  });
}

async function processImages(inputFolder = "input", outputFolder = "output", size = 175) {
  try {
    await Promise.all([ensureDir(inputFolder), ensureDir(outputFolder)])

    const files = await fs.promises.readdir(inputFolder);

    const imageFiles = files.filter(file => {
      const ext = path.extname(file).toLowerCase();
      return ['.jpg', '.jpeg', '.png', '.heic'].includes(ext);
    });

    for (const file of imageFiles) {
      const inputPath = path.join(inputFolder, file);
      const outputPath = path.join(outputFolder, file);

      sharp(inputPath)
        .grayscale()
        .resize(size, size, { fit: "cover" })
        .toFormat("png")
        .toFile(addPngExtension(outputPath), (err, info) => {
          if (err) {
            console.error(`Error processing ${file}:`, err);
          } else {
            console.log(`Processed ${file}:`, info);
          }
        });
    }
  } catch (error) {
    console.error('Error:', error);
  }
}

await processImages();