diff --git a/src/util/AreaMap2D.hpp b/src/util/AreaMap2D.hpp
index 54c10657..3b550ae2 100644
--- a/src/util/AreaMap2D.hpp
+++ b/src/util/AreaMap2D.hpp
@@ -104,9 +104,12 @@ namespace util {
                 return false;
             }
             auto& element = firstBuffer[ly * sizeX + lx];
-            if (!element) {
+            if (value && !element) {
                 valuesCount++;
             }
+            if (element && !value) {
+                valuesCount--;
+            }
             element = std::move(value);
             return true;
         }
diff --git a/test/util/AreaMap2D.cpp b/test/util/AreaMap2D.cpp
index 4fdd78fe..a4535926 100644
--- a/test/util/AreaMap2D.cpp
+++ b/test/util/AreaMap2D.cpp
@@ -1,7 +1,78 @@
 #include <gtest/gtest.h>
+#include <atomic>
 
 #include "util/AreaMap2D.hpp"
 
 TEST(AreaMap2D, BaseTest) {
-    util::AreaMap2D<int> window({6, 6});
+    util::AreaMap2D<int> window({7, 5});
+    window.setCenter(0, 0);
+    {
+        int i = 1;
+        for (int y = -2; y <= 2; y++) {
+            for (int x = -3; x <= 3; x++, i++) {
+                window.set(x, y, i);
+            }
+        }
+    }
+    EXPECT_EQ(window.count(), 7 * 5);
+    {
+        int i = 1;
+        for (int y = -2; y <= 2; y++) {
+            for (int x = -3; x <= 3; x++, i++) {
+                EXPECT_EQ(window.require(x, y), i);
+            }
+        }
+    }
+    window.set(0, 0, 0);
+    EXPECT_EQ(window.count(), 7 * 5 - 1);
+}
+
+
+TEST(AreaMap2D, ResizeTest) {
+    util::AreaMap2D<int> window({7, 5});
+    window.setCenter(0, 0);
+    {
+        int i = 1;
+        for (int y = -2; y <= 2; y++) {
+            for (int x = -3; x <= 3; x++, i++) {
+                window.set(x, y, i);
+            }
+        }
+    }
+    EXPECT_EQ(window.count(), 7 * 5);
+    window.resize(9, 7);
+    window.setCenter(0, 0);
+    EXPECT_EQ(window.count(), 7 * 5);
+    window.resize(7, 5);
+
+    EXPECT_EQ(window.count(), 7 * 5);
+    {
+        int i = 1;
+        for (int y = -2; y <= 2; y++) {
+            for (int x = -3; x <= 3; x++, i++) {
+                EXPECT_EQ(window.require(x, y), i);
+            }
+        }
+    }
+}
+
+TEST(AreaMap2D, TranslateWithOut) {
+    util::AreaMap2D<int> window({7, 5});
+    window.setCenter(0, 0);
+    {
+        int i = 1;
+        for (int y = -2; y <= 2; y++) {
+            for (int x = -3; x <= 3; x++, i++) {
+                window.set(x, y, i);
+            }
+        }
+    }
+    std::atomic_int outside = 0;
+    window.setOutCallback([&outside](auto, auto, auto) {
+        outside++;
+    });
+    window.setCenter(-2, -1);
+    EXPECT_EQ(window.require(-3, -2), 1);
+    EXPECT_EQ(outside, 15);
+    EXPECT_EQ(window.count(), 20);
 }
diff --git a/test/world/generator/SurroundMap.cpp b/test/world/generator/SurroundMap.cpp
index b61db149..7131ff94 100644
--- a/test/world/generator/SurroundMap.cpp
+++ b/test/world/generator/SurroundMap.cpp
@@ -5,22 +5,28 @@
 
 TEST(SurroundMap, InitTest) {
     int maxLevelZone = 50;
-    int x = 20;
-    int y = 30;
+    int x = 0;
+    int y = 0;
     int8_t maxLevel = 5;
-    std::atomic_int affected = 0;
 
     SurroundMap map(maxLevelZone, maxLevel);
+    std::atomic_int affected = 0;
+
     map.setLevelCallback(1, [&affected](auto, auto) {
         affected++;
     });
+    map.setCenter(0, 0);
     map.completeAt(x, y);
-    EXPECT_EQ(affected, (maxLevel * 2 - 1)*(maxLevel * 2 - 1));
+    EXPECT_EQ(affected, (maxLevel * 2 - 1) * (maxLevel * 2 - 1));
 
-    for (int ly = -maxLevel+1; ly < maxLevel; ly++) {
-        for (int lx = -maxLevel+1; lx < maxLevel; lx++) {
-            int levelExpected = maxLevel-std::max(std::abs(lx), std::abs(ly));
-            EXPECT_EQ(map.at(x+lx, y+ly), levelExpected);
+    for (int ly = -maxLevel + 1; ly < maxLevel; ly++) {
+        for (int lx = -maxLevel + 1; lx < maxLevel; lx++) {
+            int levelExpected = maxLevel - std::max(std::abs(lx), std::abs(ly));
+            EXPECT_EQ(map.at(x + lx, y + ly), levelExpected);
         }
     }
+
+    affected = 0;
+    map.completeAt(x - 1, y);
+    EXPECT_EQ(affected, maxLevel * 2 - 1);
 }