diff --git a/session_data.cpp b/session_data.cpp
index 48e5468..98ca0a5 100644
--- a/session_data.cpp
+++ b/session_data.cpp
@@ -39,19 +39,19 @@ short SurfaceData::getSurface(coord& point) {
     return surfaceMatrix[point.x][point.y];
 }
 
-bool SurfaceData::IsValidCoord(coord& point) {
+bool SurfaceData::CoordIsValid(coord& point) {
     if ((point.x < 0 || point.x > mapWidth) || (point.y < 0 || point.y > mapHeight))
         return false;
     return true;
 }
 
-bool SurfaceData::IsValidRadius(coord& point, short radius) {
+bool SurfaceData::RadiusIsValid(coord& point, short radius) {
     if (
         (point.x - radius <= 0) || 
         (point.x + radius >= mapWidth) || 
         (point.y + radius >= mapHeight) ||
         (point.y - radius <= 0) ||
-        (!IsValidCoord(point))
+        (!CoordIsValid(point))
     ) return false;
 
     bool flag = false;
diff --git a/session_data.h b/session_data.h
index ac7e951..ba5c474 100644
--- a/session_data.h
+++ b/session_data.h
@@ -29,14 +29,15 @@ class SurfaceData {
     bool Init();
     int getWidth();
     int getHeight();
-    bool IsValidRadius(coord&, short);
-    bool IsValidCoord(coord&);
+    bool RadiusIsValid(coord&, short);
     bool IsWalkable(coord&);
     short getSurface(coord&);
     Surface& getSurface(str);   
 private:
+    bool CoordIsValid(coord&);
     int mapWidth, mapHeight;
-    short** surfaceMatrix;    // std::unordered_map<str, Surface> currentSurfaceList; // currently useless
+    short** surfaceMatrix;    
+    // std::unordered_map<str, Surface> currentSurfaceList; // currently useless
     // std::unordered_map<str, Surface> globalSurfaceList; //will be added in future
 };