Render surface maps directly and preserve their quality

scripts/render-map.mjs

@@ -0,0 +1,20 @@
+import { readFile, mkdir } from "node:fs/promises";
+import { dirname, resolve } from "node:path";
+import { gunzipSync } from "node:zlib";
+import { renderSurfaceMap } from "../renderer/surface-map.mjs";
+
+const [input, output] = process.argv.slice(2);
+if (!input || !output)
+  throw new Error(
+    "Usage: npm run render:map -- <terrain.json.gz> <output.webp>",
+  );
+const terrain = JSON.parse(
+  gunzipSync(await readFile(input), {
+    maxOutputLength: 256 * 1024 * 1024,
+  }).toString(),
+);
+await mkdir(dirname(resolve(output)), { recursive: true });
+const report = await renderSurfaceMap(terrain, output);
+console.log(
+  `Rendered ${report.width} × ${report.height} map cells from ${report.columns.toLocaleString()} surface columns: ${output}`,
+);