diff --git a/src/Map.cpp b/src/Map.cpp
index 58fd035..bd81064 100644
--- a/src/Map.cpp
+++ b/src/Map.cpp
@@ -185,23 +185,22 @@ void Map::shift(Point& pointToShift, Direction direction) const
 
 void Map::tagAreaAsChanged(Point leftUpper, Point rightLower)
 {
-    const int tileSize{Config::getInstance().getTileSize()};
     TilePosition position{screenPointToTilePosition(leftUpper)};
     if (point_utils::isValidPoint(leftUpper))
         changedTiles_[position.x_][position.y_] = tileChanged_;
 
-    position =
-        screenPointToTilePosition({leftUpper.x_, leftUpper.y_ + tileSize});
-    if (point_utils::isValidPoint({leftUpper.x_, leftUpper.y_ + tileSize}))
+    Point point{leftUpper.x_, rightLower.y_};
+    position = screenPointToTilePosition(point);
+    if (point_utils::isValidPoint(point))
         changedTiles_[position.x_][position.y_] = tileChanged_;
 
     position = screenPointToTilePosition(rightLower);
     if (point_utils::isValidPoint(rightLower))
         changedTiles_[position.x_][position.y_] = tileChanged_;
 
-    position = screenPointToTilePosition(
-        Point{rightLower.x_, rightLower.y_ - tileSize});
-    if (point_utils::isValidPoint({rightLower.x_, rightLower.y_ - tileSize}))
+    point = {rightLower.x_, leftUpper.y_};
+    position = screenPointToTilePosition(point);
+    if (point_utils::isValidPoint(point))
         changedTiles_[position.x_][position.y_] = tileChanged_;
 }
 
diff --git a/test/FakeDisplay.h b/test/FakeDisplay.h
index d55e79b..109f044 100644
--- a/test/FakeDisplay.h
+++ b/test/FakeDisplay.h
@@ -1,10 +1,19 @@
 #pragma once
 
+#include <vector>
+
 #include <src/Display.h>
 
 class FakeDisplay : public Display
 {
 public:
+    struct ChangedArea
+    {
+        ResourceType type_;
+        int x_;
+        int y_;
+    };
+
     bool init() override { return true; };
 
     void drawText([[maybe_unused]] int x, [[maybe_unused]] int y,
@@ -20,7 +29,10 @@ class FakeDisplay : public Display
     void drawScaledBitmap([[maybe_unused]] ResourceType resourceType,
                           [[maybe_unused]] int x, [[maybe_unused]] int y,
                           [[maybe_unused]] int width,
-                          [[maybe_unused]] int height) const override {};
+                          [[maybe_unused]] int height) const override
+    {
+        changedAreas_.push_back({resourceType, x, y});
+    };
 
     void drawScaledBitmapWithRotation(
         [[maybe_unused]] ResourceType resourceType, [[maybe_unused]] int x,
@@ -54,7 +66,13 @@ class FakeDisplay : public Display
 
     void useWindowedMode() override {};
 
+    std::vector<ChangedArea> getChangedAreas() const { return changedAreas_; }
+
+    void resetChangedAreas() { changedAreas_.clear(); }
+
 private:
     int resourceWidth_;
     int resourceHeight_;
+
+    mutable std::vector<ChangedArea> changedAreas_;
 };
diff --git a/test/MapTest.cpp b/test/MapTest.cpp
index 9f107f5..a54a270 100644
--- a/test/MapTest.cpp
+++ b/test/MapTest.cpp
@@ -9,6 +9,8 @@
 #include <src/Tank.h>
 #include <src/Utils.h>
 
+#include "FakeDisplay.h"
+
 // 0 - plain
 // 1 - brick
 // 2 - water
@@ -306,3 +308,84 @@ TEST_CASE("shift", "[map]")
         REQUIRE(pointToShift == expectedShiftedPoint);
     }
 }
+
+TEST_CASE("changed area", "[map]")
+{
+    const int tileSize{Config::getInstance().getTileSize()};
+
+    Map map(tileCount);
+    std::stringstream stream(getTestMap());
+    map.loadMap(stream);
+
+    FakeDisplay display;
+    map.drawBackground(display);
+    map.drawForeground(display);
+
+    SECTION("First draw on display")
+    {
+        REQUIRE(display.getChangedAreas().size() == (25 + 1));
+    }
+
+    display.resetChangedAreas();
+
+    SECTION("change one tile and draw background")
+    {
+        map.tagAreaAsChanged({0, 0}, {0, 0});
+        map.drawBackground(display);
+        auto changed{display.getChangedAreas()};
+        REQUIRE(display.getChangedAreas().size() == 1);
+    }
+
+    SECTION("change 2 tiles in line and draw background")
+    {
+        map.tagAreaAsChanged({0, 0}, {tileSize, 0});
+        map.drawBackground(display);
+        REQUIRE(display.getChangedAreas().size() == 2);
+    }
+
+    SECTION("change 2 tiles in column and draw background")
+    {
+        map.tagAreaAsChanged({0, 0}, {0, tileSize});
+        map.drawBackground(display);
+        REQUIRE(display.getChangedAreas().size() == 2);
+    }
+
+    SECTION("change 4 tiles and draw background")
+    {
+        map.tagAreaAsChanged({0, 0}, {tileSize, tileSize});
+        map.drawBackground(display);
+        REQUIRE(display.getChangedAreas().size() == 4);
+    }
+
+    SECTION("change one tile and draw foreground")
+    {
+        map.tagAreaAsChanged({3 * tileSize, 3 * tileSize},
+                             {3 * tileSize, 3 * tileSize});
+        map.drawForeground(display);
+        REQUIRE(display.getChangedAreas().size() == 1);
+    }
+
+    SECTION("change 2 tiles in line and draw foreground")
+    {
+        map.tagAreaAsChanged({3 * tileSize, 3 * tileSize},
+                             {4 * tileSize, 3 * tileSize});
+        map.drawForeground(display);
+        REQUIRE(display.getChangedAreas().size() == 1);
+    }
+
+    SECTION("change 2 tiles in column and draw foreground")
+    {
+        map.tagAreaAsChanged({3 * tileSize, 3 * tileSize},
+                             {3 * tileSize, 4 * tileSize});
+        map.drawForeground(display);
+        REQUIRE(display.getChangedAreas().size() == 1);
+    }
+
+    SECTION("change 4 tiles and draw foreground")
+    {
+        map.tagAreaAsChanged({3 * tileSize, 3 * tileSize},
+                             {4 * tileSize, 4 * tileSize});
+        map.drawForeground(display);
+        REQUIRE(display.getChangedAreas().size() == 1);
+    }
+}