Render textured aerial maps and support legacy recovery links

renderer/map-view.mjs

@@ -0,0 +1,19 @@
+// Keep one world block square in the image, including rectangular exports.
+// Eight pixels per block preserves the vanilla textures in typical 128-block
+// exports; large worlds are capped to a manageable image size.
+export function mapDimensions(bounds) {
+  const spanX = bounds.maxX - bounds.minX;
+  const spanZ = bounds.maxZ - bounds.minZ;
+  if (
+    !Number.isInteger(spanX) ||
+    !Number.isInteger(spanZ) ||
+    spanX < 1 ||
+    spanZ < 1
+  )
+    throw new Error("Surface map bounds must have a positive integer size");
+  const scale = Math.min(8, 2048 / Math.max(spanX, spanZ));
+  return {
+    width: Math.max(1, Math.round(spanX * scale)),
+    height: Math.max(1, Math.round(spanZ * scale)),
+  };
+}