diff --git a/source/build/include/sdlayer.h b/source/build/include/sdlayer.h
index c6545428c..c31ecc361 100644
--- a/source/build/include/sdlayer.h
+++ b/source/build/include/sdlayer.h
@@ -37,26 +37,29 @@ int32_t SDL_WaitEventTimeout(SDL_Event *event, int32_t timeout);
     }
 
 #define SDL_ADDMODE(x, y, c, f)                                                                                        \
-    do                                                                                                                 \
     {                                                                                                                  \
-        if (validmodecnt < MAXVALIDMODES)                                                                              \
+        int fullscreen;                                                                                                \
+        for (fullscreen = f; fullscreen >= 0; --fullscreen)                                                            \
         {                                                                                                              \
-            int32_t mn;                                                                                                \
-            for (mn = 0; mn < validmodecnt; mn++)                                                                      \
-                if (validmode[mn].xdim == x && validmode[mn].ydim == y && validmode[mn].bpp == c &&                    \
-                    validmode[mn].fs == f)                                                                             \
-                    break;                                                                                             \
-            if (mn == validmodecnt)                                                                                    \
+            if (validmodecnt < MAXVALIDMODES)                                                                          \
             {                                                                                                          \
-                validmode[validmodecnt].xdim = x;                                                                      \
-                validmode[validmodecnt].ydim = y;                                                                      \
-                validmode[validmodecnt].bpp = c;                                                                       \
-                validmode[validmodecnt].fs = f;                                                                        \
-                validmodecnt++;                                                                                        \
-                /*initprintf("  - %dx%d %d-bit %s\n", x, y, c, (f&1)?"fullscreen":"windowed");*/                       \
+                int32_t mn;                                                                                            \
+                for (mn = 0; mn < validmodecnt; mn++)                                                                  \
+                    if (validmode[mn].xdim == x && validmode[mn].ydim == y && validmode[mn].bpp == c &&                \
+                        validmode[mn].fs == fullscreen)                                                                \
+                        break;                                                                                         \
+                if (mn == validmodecnt)                                                                                \
+                {                                                                                                      \
+                    validmode[validmodecnt].xdim = x;                                                                  \
+                    validmode[validmodecnt].ydim = y;                                                                  \
+                    validmode[validmodecnt].bpp = c;                                                                   \
+                    validmode[validmodecnt].fs = fullscreen;                                                           \
+                    validmodecnt++;                                                                                    \
+                    /*initprintf("  - %dx%d %d-bit %s\n", x, y, c, (fullscreen&1)?"fullscreen":"windowed");*/          \
+                }                                                                                                      \
             }                                                                                                          \
         }                                                                                                              \
-    } while (0)
+    }
 
 #define SDL_CHECKMODE(w, h) ((w < MAXXDIM) && (h < MAXYDIM) && (w >= MINXDIM) && (h >= MINYDIM) && (((float)w/(float)h) >= 1.3f))
 
diff --git a/source/build/src/winlayer.cpp b/source/build/src/winlayer.cpp
index 8980e5d49..bdc755297 100644
--- a/source/build/src/winlayer.cpp
+++ b/source/build/src/winlayer.cpp
@@ -1655,16 +1655,23 @@ int32_t setvideomode(int32_t x, int32_t y, int32_t c, int32_t fs)
 //
 // getvalidmodes() -- figure out what video modes are available
 //
-#define ADDMODE(x,y,c,f,n) if (validmodecnt<MAXVALIDMODES) { \
-    validmode[validmodecnt].xdim=x; \
-    validmode[validmodecnt].ydim=y; \
-    validmode[validmodecnt].bpp=c; \
-    validmode[validmodecnt].fs=f; \
-    validmode[validmodecnt].extra=n; \
-    validmodecnt++; \
-}
-/*	initprintf("  - %dx%d %d-bit %s\n", x, y, c, (f&1)?"fullscreen":"windowed"); \
-} */
+#define ADDMODE(x,y,c,f,n)                                                                          \
+    {                                                                                               \
+        int fullscreen;                                                                             \
+        for (fullscreen = f; fullscreen >= 0; --fullscreen)                                         \
+        {                                                                                           \
+            if (validmodecnt<MAXVALIDMODES)                                                         \
+            {                                                                                       \
+                validmode[validmodecnt].xdim=x;                                                     \
+                validmode[validmodecnt].ydim=y;                                                     \
+                validmode[validmodecnt].bpp=c;                                                      \
+                validmode[validmodecnt].fs=fullscreen;                                              \
+                validmode[validmodecnt].extra=n;                                                    \
+                validmodecnt++;                                                                     \
+/*           initprintf("  - %dx%d %d-bit %s\n", x, y, c, (fullscreen&1)?"fullscreen":"windowed");*/\
+            }                                                                                       \
+        }                                                                                           \
+    }
 
 #define CHECK(w,h) if ((w < maxx) && (h < maxy))