diff --git a/Sources/Engine/Base/SDL/SDLEvents.cpp b/Sources/Engine/Base/SDL/SDLEvents.cpp
index 512cfce..6ef1800 100644
--- a/Sources/Engine/Base/SDL/SDLEvents.cpp
+++ b/Sources/Engine/Base/SDL/SDLEvents.cpp
@@ -59,7 +59,7 @@ BOOL PeekMessage(MSG *msg, void *hwnd, UINT wMsgFilterMin,
             break;
 
         case SDL_MOUSEBUTTONDOWN:
-            if (sdlevent.button.button == 2)  // right button...
+            if (sdlevent.button.button == SDL_BUTTON_RIGHT)  // right button...
             {
                 msg->message = WM_RBUTTONDOWN;
             } // if
@@ -78,7 +78,7 @@ BOOL PeekMessage(MSG *msg, void *hwnd, UINT wMsgFilterMin,
             break;
 
         case SDL_MOUSEBUTTONUP:
-            if (sdlevent.button.button == 2)  // right button...
+            if (sdlevent.button.button == SDL_BUTTON_RIGHT)  // right button...
             {
                 msg->message = WM_RBUTTONUP;
             } // if
diff --git a/Sources/Engine/Base/SDL/SDLInput.cpp b/Sources/Engine/Base/SDL/SDLInput.cpp
index 332fa72..07f985d 100644
--- a/Sources/Engine/Base/SDL/SDLInput.cpp
+++ b/Sources/Engine/Base/SDL/SDLInput.cpp
@@ -328,13 +328,13 @@ static void sdl_event_handler(const SDL_Event *event)
         case SDL_MOUSEBUTTONDOWN:
             switch (event->button.button)
             {
-                case 1:
+                case SDL_BUTTON_LEFT:
                     _abKeysPressed[KID_MOUSE1] = TRUE;
                     break;
-                case 2:
+                case SDL_BUTTON_RIGHT:
                     _abKeysPressed[KID_MOUSE2] = TRUE;
                     break;
-                case 3:
+                case SDL_BUTTON_MIDDLE:
                     _abKeysPressed[KID_MOUSE3] = TRUE;
                     break;
 
@@ -351,13 +351,13 @@ static void sdl_event_handler(const SDL_Event *event)
         case SDL_MOUSEBUTTONUP:
             switch (event->button.button)
             {
-                case 1:
+                case SDL_BUTTON_LEFT:
                     _abKeysPressed[KID_MOUSE1] = FALSE;
                     break;
-                case 2:
+                case SDL_BUTTON_RIGHT:
                     _abKeysPressed[KID_MOUSE2] = FALSE;
                     break;
-                case 3:
+                case SDL_BUTTON_MIDDLE:
                     _abKeysPressed[KID_MOUSE3] = FALSE;
                     break;