diff --git a/include/snake.h b/include/snake.h
index 5f6990d..ddd784a 100644
--- a/include/snake.h
+++ b/include/snake.h
@@ -39,6 +39,9 @@ bool snakeIsAlive();
 // Überprüfen, ob Schlange noch lebt
 // Prüft Kollision mit sich selbst
 
-void snakeSetHeadPos(); // optional
+void snakeSetHeadPos(int xPos, int yPos); // optional
 // für handlePortals
-// generiert zufällige Zielsposition, wohin sich die Schlange nach Betreten eines Portals bewegt
\ No newline at end of file
+// generiert zufällige Zielposition(Übergabeparameter), wohin sich die Schlange nach Betreten eines Portals bewegt
+
+void snakeUpdateHeadPos();
+// berechnet neue Position des Kopfs anhand der aktuellen Bewegungsrichtung
\ No newline at end of file
diff --git a/src/game.c b/src/game.c
index 1e4b1ab..7cc247d 100644
--- a/src/game.c
+++ b/src/game.c
@@ -38,6 +38,7 @@ void gameInit()
     //load default map if no map loaded yet
     if (!game.mapIsLoaded){
         loadMapByName("default");
+        //loadMapByName("empty");
         //loadMapByName("intermediate");
     }
     
@@ -92,8 +93,10 @@ void runGameCycle()
         // show leaderboard when collided
         // TODO consider game.lifesRemaining and reset if still good?
         LOGI("game: collided with wall or self! => show leaderboard\n");
-        game.gameState = MENU;
-        showLeaderboard();
+        LOGI("DEBUG: collision currently disabled, game will continue in 1s...\n");
+        DELAY(1000);
+        //game.gameState = MENU; //TODO add config.collisionEnabled option?
+        //showLeaderboard();
         return;
     }
 
@@ -103,13 +106,13 @@ void runGameCycle()
     //--- handle food ---
     if (checkEaten()) {
         LOGI("game: picked up food at x=%d y=%d -> growing, placing food\n", game.foodX, game.foodY);
+        // NOTE: order of place and grow is relevant, otherwise function in food.c will access invalid memory
+        placeFood(); 
         snakeGrow();
-        placeFood();
-    }
+}
 
     //--- update frame ---
-    
     renderGame();
-    //printMap(game.map); (render game to console)
+    printMap(game.map); //render game to console
     return;
 }
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index a3000e1..c1efde5 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -20,6 +20,18 @@ extern "C"{
 //uninitialize SDL
 
 
+
+//==========================
+//====== enabled test ======
+//==========================
+//uncomment one test at a time to run the corresponding code in main()
+//#define TEST__FOOD_PLACEMENT
+//#define TEST__SDL_INPUT
+#define TEST__GAME_WITH_CONSOLE_OUTPUT
+
+
+
+
 int main(int argc, char *argv[])
 {
   gameInit();
diff --git a/src/map.c b/src/map.c
index 13eec17..22a669a 100644
--- a/src/map.c
+++ b/src/map.c
@@ -28,7 +28,7 @@ void renderGameToArray(int mapFrame[MAX_MAP_SIZE][MAX_MAP_SIZE], map_t map, snak
     {
         mapFrame[snake.tail[i][1]][snake.tail[i][0]] = 5;
     }
-    // copy food
+     // copy food
     mapFrame[game.foodY][game.foodX] = 6;
     // copy snake head (last element -> head overwrites previous elements)
     mapFrame[snake.headY][snake.headX] = 4;
@@ -205,6 +205,22 @@ static const map_t map_default = {
          .color = "blue"}},
     .portalCount = 1};
 
+
+static const map_t map_empty = {
+    .width = 20,
+    .height = 10,
+    .name = "empty",
+    .collisions = {},
+    .collisionCount = 0,
+    .portals = {
+        {.posX = 5,
+         .posY = 8,
+         .targetX = 7,
+         .targetY = 1,
+         .color = "blue"}},
+    .portalCount = 1};
+
+
 static const map_t map_intermediate = {
     .width = 15,
     .height = 15,
@@ -225,5 +241,5 @@ static const map_t map_intermediate = {
     .portalCount = 2};
 
 // global variables for accessing the stored maps
-const map_t *storedMaps[16] = {&map_default, &map_intermediate};
-const int storedMapsCount = 2;
\ No newline at end of file
+const map_t *storedMaps[16] = {&map_default, &map_empty, &map_intermediate};
+const int storedMapsCount = 3;
\ No newline at end of file
diff --git a/src/snake.c b/src/snake.c
index 42f8c94..b348b27 100644
--- a/src/snake.c
+++ b/src/snake.c
@@ -45,8 +45,8 @@ void snakeMove()
 {   
     int i = game.snake.length - 1;  // counter for snake moving
 
-    // update head position
-    snakeSetHeadPos();
+    // update head position automatically
+    snakeUpdateHeadPos();
 
     // tail part of[x,y][0,1] get coordinates of tail part before
     while(i)
@@ -77,9 +77,19 @@ bool snakeIsAlive()
     return true;
 }
 
-void snakeSetHeadPos()
+void snakeSetHeadPos(int xPos, int yPos)
 {
-        switch(game.snake.direction)
+    game.snake.headX = xPos;
+    game.snake.headY = yPos;
+    game.snake.tail[0][0] = xPos;
+    game.snake.tail[0][1] = yPos;
+    return;
+}
+
+
+void snakeUpdateHeadPos()
+{
+    switch(game.snake.direction)
     {   
         // DOWN
         case DOWN: