Various fixes

items.lua

@@ -413,10 +413,10 @@ local function copy_map_item(stack)
         local new_id = maps.create(src.x, src.z, src.w, src.h, false, src.detail, src.scale);
         local dest = maps.get(new_id);
         for k,v in pairs(src.fill) do
-            dest.fill[k] = v;
+            dest.fill[k] = table.copy(v);
         end
         for k,v in pairs(src.markers) do
-            dest.markers[k] = v;
+            dest.markers[k] = table.copy(v);
         end
 
         copy_meta:set_int("cartographer:map_id", new_id);

map_api.lua

@@ -19,7 +19,6 @@ function Map.resize(self, w, h)
     if w >= self.w and h >= self.h then
         self.w = w;
         self.h = h;
-        -- FIXME: Is this really correct? Seems questionable.
     end
 end
 
@@ -32,8 +31,12 @@ end
 -- h: The height, in map coordinates
 function Map.fill_area(self, x, z, w, h)
     for i = math.max(x, 0),math.min(x + w - 1, self.w),1 do
+        if not self.fill[i] then
+            self.fill[i] = {};
+        end
+
         for j = math.max(z, 0),math.min(z + h - 1, self.h),1 do
-            self.fill[i + (j * self.w)] = self.detail;
+            self.fill[i][j] = self.detail;
         end
     end
 end
@@ -112,7 +115,7 @@ end
 -- x: The x position, in map coordinates
 -- z: The z position, in map coordinates
 function Map.is_filled(self, x, z)
-    return self.fill[(x - self.x) + ((z - self.z) * self.w)] ~= nil;
+    return self.fill[x - self.x] and self.fill[x - self.x][z - self.z];
 end
 
 -- The Map API

scanner.lua

@@ -238,9 +238,7 @@ end
 --
 -- flush: Flush the entire scan queue, scanning all queued regions
 function scanner.scan_regions(flush)
-    local len = #scan_queue;
-
-    if len == 0 then
+    if #scan_queue == 0 then
         return;
     end
 
@@ -250,6 +248,10 @@ function scanner.scan_regions(flush)
         end
     else
         for _=1,settings.backup_scan_count do
+            if #scan_queue == 0 then
+                break;
+            end
+
             scan_internal();
         end
     end