diff --git a/srv/game/world.cpp b/srv/game/world.cpp
index 3039b0b..0518096 100644
--- a/srv/game/world.cpp
+++ b/srv/game/world.cpp
@@ -1,4 +1,5 @@
 #include <chrono>
+#include <cmath>
 
 #include "world.h"
 #include "bettola/game/chunk.h"
@@ -38,7 +39,7 @@ void World::_generate_chunk(BettolaLib::Game::Chunk& chunk, int chunk_x, int chu
         + (z - BettolaLib::Game::CHUNK_BORDER_SIZE));
 
       /* generate noise value. */
-      chunk.heightmap[z * BettolaLib::Game::CHUNK_DATA_WIDTH + x] = _noise.GetNoise(world_x, world_z);
+      chunk.heightmap[z * BettolaLib::Game::CHUNK_DATA_WIDTH + x] = fabsf(_noise.GetNoise(world_x, world_z));
     }
   }
 }