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[NTVDM]

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Fix CGA emulation in shift interleave mode.
CORE-8177 #comment Possibly fixed. Can you redo your tests with r63199?


svn path=/trunk/; revision=63199
This commit is contained in:
Aleksandar Andrejevic 2014-05-09 00:15:40 +00:00
parent 0ef1e2610a
commit ef8bb583c9
2 changed files with 21 additions and 6 deletions
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25
reactos/subsystems/ntvdm/hardware/vga.c
View file

@ -1146,6 +1146,8 @@ static VOID VgaUpdateFramebuffer(VOID)
/* Loop through the scanlines */
for (i = 0; i < Resolution.Y; i++)
{
BOOL RepeatScanline = FALSE;
/* Loop through the pixels */
for (j = 0; j < Resolution.X; j++)
{
@ -1199,10 +1201,23 @@ static VOID VgaUpdateFramebuffer(VOID)
* 2 bits shifted from plane 0 and 2 for the first 4 pixels,
* then 2 bits shifted from plane 1 and 3 for the next 4
*/
BYTE LowPlaneData = VgaMemory[((j / 4) % 2) * VGA_BANK_SIZE
+ (Address + (j / 8)) * AddressSize];
BYTE HighPlaneData = VgaMemory[(((j / 4) % 2) + 2) * VGA_BANK_SIZE
+ (Address + (j / 8)) * AddressSize];
DWORD BankNumber = (j / 4) % 2;
DWORD Offset = Address + (j / 8);
BYTE LowPlaneData, HighPlaneData;
if (i % 2 == 0)
{
/* Odd-numbered line - add the CGA emulation offset */
Offset += VGA_CGA_ODD_LINE_OFFSET;
}
else
{
/* Even-numbered line - use the same scanline */
RepeatScanline = TRUE;
}
LowPlaneData = VgaMemory[BankNumber * VGA_BANK_SIZE + Offset * AddressSize];
HighPlaneData = VgaMemory[(BankNumber + 2) * VGA_BANK_SIZE + Offset * AddressSize];
/* Extract the two bits from each plane */
LowPlaneData = (LowPlaneData >> (6 - ((j % 4) * 2))) & 3;
@ -1296,7 +1311,7 @@ static VOID VgaUpdateFramebuffer(VOID)
}
/* Move to the next scanline */
Address += ScanlineSize;
if (!RepeatScanline) Address += ScanlineSize;
}
/*

2
reactos/subsystems/ntvdm/hardware/vga.h
View file

@ -24,7 +24,7 @@
#define VGA_MINIMUM_HEIGHT 300
#define VGA_DAC_TO_COLOR(x) (((x) << 2) | ((x) >> 4))
#define VGA_COLOR_TO_DAC(x) ((x) >> 2)
#define VGA_CGA_ODD_LINE_OFFSET 0x1000
/* Register I/O ports */