diff --git a/win32ss/gdi/dib/dib1bpp.c b/win32ss/gdi/dib/dib1bpp.c
index 6a90282808..588d6cf502 100644
--- a/win32ss/gdi/dib/dib1bpp.c
+++ b/win32ss/gdi/dib/dib1bpp.c
@@ -65,6 +65,7 @@ DIB_1BPP_BitBltSrcCopy_From1BPP (
                                  BOOLEAN bTopToBottom,
                                  BOOLEAN bLeftToRight )
 {
+    DWORD Index;
     LONG Height = RECTL_lGetHeight(DestRect);
     BOOLEAN XorBit = !!XLATEOBJ_iXlate(pxlo, 0);
 
@@ -74,25 +75,77 @@ DIB_1BPP_BitBltSrcCopy_From1BPP (
     ASSERT(Height > 0);
     ASSERT(RECTL_lGetWidth(DestRect) > 0);
 
-    while (Height--)
+    if (!bLeftToRight && !bTopToBottom)
     {
+      while (Height--)
+      {
         LONG yDst = DestRect->top + Height;
-        LONG ySrc = bTopToBottom ?
-            SourcePoint->y + RECTL_lGetHeight(DestRect) - Height
-            : SourcePoint->y + Height;
+        LONG ySrc = SourcePoint->y + Height;
         LONG Width = RECTL_lGetWidth(DestRect);
 
         while (Width--)
         {
             LONG xDst = DestRect->left + Width;
-            LONG xSrc = bLeftToRight ?
-                SourcePoint->x + RECTL_lGetWidth(DestRect) - Width
-                : SourcePoint->x + Width;
+            LONG xSrc = SourcePoint->x + Width;
             ULONG PixelPut = DIB_1BPP_GetPixel(SourceSurf, xSrc, ySrc);
             if (XorBit)
                 PixelPut = !PixelPut;
             DIB_1BPP_PutPixel(DestSurf, xDst, yDst, PixelPut);
+          }
+      }
+    }
+    else if (bLeftToRight && !bTopToBottom)
+    {
+      DPRINT1("Flip is bLeftToRight.\n");
+
+      /* Allocate enough pixels for a row in DWORD's */
+      DWORD *store = ExAllocatePoolWithTag(NonPagedPool,
+        (RECTL_lGetWidth(DestRect) + 1) * 4, TAG_DIB);
+      if (store == NULL)
+      {
+        DPRINT1("Storage Allocation Failed.\n");
+        return;
+      }
+
+      while (Height--)
+      {
+        LONG yDst = DestRect->top + Height;
+        LONG ySrc = SourcePoint->y + Height;
+
+        LONG Width = RECTL_lGetWidth(DestRect);
+        Index = 0;
+
+        while (Width--)
+        {
+            LONG xSrc = SourcePoint->x + RECTL_lGetWidth(DestRect) - Width - 1;
+            ULONG PixelPut = DIB_1BPP_GetPixel(SourceSurf, xSrc, ySrc);
+            if (XorBit)
+                PixelPut = !PixelPut;
+            store[Index] = PixelPut;
+            Index++;
+        }
+
+        Width = RECTL_lGetWidth(DestRect);
+        Index = 0;
+
+        while (Width--)
+        {
+            LONG xDst = DestRect->left + Width;
+            DIB_1BPP_PutPixel(DestSurf, xDst, yDst, store[Index]);
+            Index++;
         }
+
+      } // While (Height--)
+
+      ExFreePoolWithTag(store, TAG_DIB);
+    }
+    else if (!bLeftToRight && bTopToBottom)
+    {
+      DPRINT1("bTopToBottom and no bLeftToRight not handled yet!\n");
+    }
+    else
+    {
+      DPRINT1("Both bLeftToRight and bTopToBottom not handled yet!\n");
     }
 }