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[NTVDM]

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Properly clear the video memory when switching to a different mode.


svn path=/trunk/; revision=68091
This commit is contained in:
Aleksandar Andrejevic 2015-06-09 14:48:30 +00:00
parent e730ef4e7d
commit a9a14ab22b
1 changed files with 39 additions and 24 deletions
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63
reactos/subsystems/mvdm/ntvdm/bios/vidbios.c
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@ -2387,6 +2387,44 @@ static inline BYTE VidBiosGetVideoMode(VOID)
return Bda->VideoMode | (Bda->VGAOptions & 0x80);
}
static inline VOID VidBiosClearScreen(VOID)
{
static const DWORD MemoryMaps[4] = { 0xA0000, 0xA0000, 0xB0000, 0xB8000 };
static const DWORD MemorySizes[4] = { 0x20000, 0x10000, 0x10000, 0x8000 };
DWORD VideoAddress;
BYTE Buffer[0x20000];
DWORD BufferSize;
BYTE Misc;
/* Read the misc register */
IOWriteB(VGA_GC_INDEX, VGA_GC_MISC_REG);
Misc = IOReadB(VGA_GC_DATA);
/* Get the video address */
VideoAddress = MemoryMaps[(Misc >> 2) & 3];
BufferSize = MemorySizes[(Misc >> 2) & 3];
if (Misc & 1)
{
/* Graphics mode */
RtlZeroMemory(Buffer, BufferSize);
}
else
{
INT i;
/* Text mode */
for (i = 0; i < (BufferSize >> 1); i++)
{
((PWORD)Buffer)[i] = MAKEWORD(' ', DEFAULT_ATTRIBUTE);
}
}
/* Write to video memory */
EmulatorWriteMemory(&EmulatorContext, VideoAddress, Buffer, BufferSize);
}
static BOOLEAN VidBiosSetVideoMode(BYTE ModeNumber)
{
BYTE Page;
@ -2503,30 +2541,7 @@ static BOOLEAN VidBiosSetVideoMode(BYTE ModeNumber)
for (Page = 0; Page < BIOS_MAX_PAGES; ++Page)
VidBiosSetCursorPosition(0, 0, Page);
// HACK: We clear here all the text memory. TODO: Do it better!
if (!DoNotClear && ((ModeNumber >= 0x00 && ModeNumber <= 0x03) || (ModeNumber == 0x07)))
{
INT i, j;
DWORD VideoAddress;
WORD FillCharacter = MAKEWORD(' ', DEFAULT_ATTRIBUTE);
for (Page = 0; Page < BIOS_MAX_PAGES; ++Page)
{
VideoAddress = TO_LINEAR(TEXT_VIDEO_SEG, Page * Bda->VideoPageSize);
for (i = 0; i <= Bda->ScreenRows; i++)
{
for (j = 0; j <= Bda->ScreenColumns - 1; j++)
{
/* Write to video memory */
EmulatorWriteMemory(&EmulatorContext,
VideoAddress + (i * Bda->ScreenColumns + j) * sizeof(WORD),
(LPVOID)&FillCharacter,
sizeof(FillCharacter));
}
}
}
}
if (!DoNotClear) VidBiosClearScreen();
/* Refresh display */
VgaRefreshDisplay();