[NTVDM]: Temporarily fix for r65015 before a proper fix.

svn path=/trunk/; revision=65018

diff --git a/reactos/subsystems/ntvdm/bios/vidbios.c b/reactos/subsystems/ntvdm/bios/vidbios.c
index 3db458f..bb5e537 100644 (file)
--- a/reactos/subsystems/ntvdm/bios/vidbios.c
+++ b/reactos/subsystems/ntvdm/bios/vidbios.c
@@ -2296,9 +2296,16 @@ static BOOLEAN VidBiosSetVideoMode(BYTE ModeNumber)
 {
     BYTE Page;
     COORD Resolution;
 {
     BYTE Page;
     COORD Resolution;

-    BOOLEAN DoNotClear = !!(ModeNumber & 0x80);

     PVGA_REGISTERS VgaMode;
 
     PVGA_REGISTERS VgaMode;
 

+    /*
+     * IBM standard modes do not clear the screen if the
+     * high bit of AL is set (EGA or higher only).
+     * See Ralf Brown: http://www.ctyme.com/intr/rb-0069.htm
+     * for more information.
+     */
+    BOOLEAN DoNotClear = !!(ModeNumber & 0x80);
+

     /* Retrieve the real mode number and check its validity */
     ModeNumber &= 0x7F;
     // if (ModeNumber >= sizeof(VideoModes)/sizeof(VideoModes[0]))
     /* Retrieve the real mode number and check its validity */
     ModeNumber &= 0x7F;
     // if (ModeNumber >= sizeof(VideoModes)/sizeof(VideoModes[0]))


@@ -2308,8 +2315,13 @@ static BOOLEAN VidBiosSetVideoMode(BYTE ModeNumber)
         return FALSE;
     }
 
         return FALSE;
     }
 

-    /* Check if this is the same mode */
-    if (ModeNumber == Bda->VideoMode) return TRUE;
+    /* Check if this is the current mode */
+    if (ModeNumber == Bda->VideoMode)
+    {
+        /* Just clear the VGA memory if needed */
+        if (!DoNotClear) VgaClearMemory();
+        return TRUE;
+    }

 
     VgaMode = VideoModes[ModeNumber];
 
 
     VgaMode = VideoModes[ModeNumber];
 


@@ -2320,12 +2332,7 @@ static BOOLEAN VidBiosSetVideoMode(BYTE ModeNumber)
 
     VgaChangePalette(ModeNumber);
 
 
     VgaChangePalette(ModeNumber);
 

-    /*
-     * IBM standard modes do not clear the screen if the
-     * high bit of AL is set (EGA or higher only).
-     * See Ralf Brown: http://www.ctyme.com/intr/rb-0069.htm
-     * for more information.
-     */
+    /* Clear the VGA memory if needed */

     if (!DoNotClear) VgaClearMemory();
 
     // Bda->CrtModeControl;
     if (!DoNotClear) VgaClearMemory();
 
     // Bda->CrtModeControl;