diff --git a/src/tools/map_extractor/System.cpp b/src/tools/map_extractor/System.cpp
index 4b5bbdfcee..9e02a67251 100644
--- a/src/tools/map_extractor/System.cpp
+++ b/src/tools/map_extractor/System.cpp
@@ -511,6 +511,7 @@ bool ConvertADT(std::string const& inputPath, std::string const& outputPath, int
         // Set map height as grid height
         for (int y = 0; y <= ADT_CELL_SIZE; y++)
         {
+            // edge V9s are overlapping between cells (i * ADT_CELL_SIZE is correct, otherwise we would be missing a row/column of V8s between)
             int cy = mcnk->iy * ADT_CELL_SIZE + y;
             for (int x = 0; x <= ADT_CELL_SIZE; x++)
             {
@@ -536,6 +537,7 @@ bool ConvertADT(std::string const& inputPath, std::string const& outputPath, int
             // get V9 height map
             for (int y = 0; y <= ADT_CELL_SIZE; y++)
             {
+                // edge V9s are overlapping between cells (i * ADT_CELL_SIZE is correct, otherwise we would be missing a row/column of V8s between)
                 int cy = mcnk->iy * ADT_CELL_SIZE + y;
                 for (int x = 0; x <= ADT_CELL_SIZE; x++)
                 {