Render textured aerial maps and support legacy recovery links

scripts/render-map.mjs

@@ -1,7 +1,7 @@
-import { readFile, mkdir } from "node:fs/promises";
-import { dirname, resolve } from "node:path";
+import { readFile, mkdir, mkdtemp, copyFile, rm } from "node:fs/promises";
+import { dirname, resolve, sep } from "node:path";
 import { gunzipSync } from "node:zlib";
-import { renderSurfaceMap } from "../renderer/surface-map.mjs";
+import { renderSnapshot } from "../renderer/render.mjs";
 
 const [input, output] = process.argv.slice(2);
 if (!input || !output)
@@ -13,8 +13,17 @@ const terrain = JSON.parse(
     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}`,
-);
+const parent = dirname(resolve(output));
+await mkdir(parent, { recursive: true });
+const temporary = await mkdtemp(resolve(parent, ".minegeo-map-"));
+try {
+  const report = await renderSnapshot(terrain, [], temporary);
+  await copyFile(resolve(temporary, "map.webp"), resolve(output));
+  console.log(
+    `Rendered ${report.map.width} × ${report.map.height} aerial map from Y=${report.map.cameraY}: ${output}`,
+  );
+} finally {
+  if (!temporary.startsWith(parent + sep))
+    throw new Error("Refusing to remove a map directory outside its parent");
+  await rm(temporary, { recursive: true, force: true });
+}

scripts/test-renderer.mjs

@@ -22,7 +22,9 @@ for (let x = -24; x < 24; x++) {
       z,
       x > 12 && z < -12
         ? "minecraft:water[level=0]"
-        : "minecraft:grass_block[snowy=false]",
+        : x < -12
+          ? "minecraft:grass_block"
+          : "minecraft:grass_block[snowy=false]",
     ]);
   }
 }
@@ -91,6 +93,32 @@ assert.equal(
   false,
 );
 await assertTerrainImage(await readFile(`${output}/map.webp`), "Surface map");
+const mapMeta = await sharp(`${output}/map.webp`).metadata();
+assert.equal(mapMeta.width, report.map.width);
+assert.equal(mapMeta.height, report.map.height);
+assert.equal(report.map.cameraY, 320);
+const { data: mapPixels, info: mapInfo } = await sharp(`${output}/map.webp`)
+  .raw()
+  .toBuffer({ resolveWithObject: true });
+const westGrass = (24 * mapInfo.width + 24) * mapInfo.channels;
+assert.ok(
+  mapPixels[westGrass + 1] > mapPixels[westGrass],
+  "blocks without explicit default properties must appear on the aerial map",
+);
+const mapPixel = (x, z) => {
+  const pixelX = Math.floor(((x - snapshot.bounds.minX + 0.5) / 48) * mapInfo.width);
+  const pixelY = Math.floor(((z - snapshot.bounds.minZ + 0.5) / 48) * mapInfo.height);
+  const offset = (pixelY * mapInfo.width + pixelX) * mapInfo.channels;
+  return mapPixels.subarray(offset, offset + 3);
+};
+if (!process.argv[2]) {
+  const shadedGrass = mapPixel(10, 9);
+  const sunlitGrass = mapPixel(10, -9);
+  assert.ok(
+    sunlitGrass[1] - shadedGrass[1] > 20,
+    "the raised building must cast a visible shadow on the aerial map",
+  );
+}
 for (const point of points) {
   for (const face of ["px", "nx", "py", "ny", "pz", "nz"]) {
     const metadata = await sharp(