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[NTVDM]

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Implement VGA panning.


svn path=/trunk/; revision=67938
This commit is contained in:
Aleksandar Andrejevic 2015-05-27 23:31:49 +00:00
parent b61240a9fd
commit 2cbf3e4d56
1 changed files with 45 additions and 19 deletions
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64
reactos/subsystems/mvdm/ntvdm/hardware/video/vga.c
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@ -1059,9 +1059,11 @@ static VOID VgaUpdateFramebuffer(VOID)
{
SHORT i, j, k;
DWORD AddressSize = VgaGetAddressSize();
DWORD Address = MAKEWORD(VgaCrtcRegisters[VGA_CRTC_START_ADDR_LOW_REG],
VgaCrtcRegisters[VGA_CRTC_START_ADDR_HIGH_REG]);
DWORD ScanlineSize = (DWORD)VgaCrtcRegisters[VGA_CRTC_OFFSET_REG] * 2;
BYTE PresetRowScan = VgaCrtcRegisters[VGA_CRTC_PRESET_ROW_SCAN_REG] & 0x1F;
DWORD Address = MAKEWORD(VgaCrtcRegisters[VGA_CRTC_START_ADDR_LOW_REG],
VgaCrtcRegisters[VGA_CRTC_START_ADDR_HIGH_REG])
+ ((VgaCrtcRegisters[VGA_CRTC_PRESET_ROW_SCAN_REG] >> 5) & 3);
/*
* If console framebuffer is NULL, that means something went wrong
@ -1075,6 +1077,7 @@ static VOID VgaUpdateFramebuffer(VOID)
/* Graphics mode */
PBYTE GraphicsBuffer = (PBYTE)ConsoleFramebuffer;
DWORD InterlaceHighBit = VGA_INTERLACE_HIGH_BIT;
SHORT X, Y;
/*
* Synchronize access to the graphics framebuffer
@ -1097,6 +1100,10 @@ static VOID VgaUpdateFramebuffer(VOID)
Address |= InterlaceHighBit;
}
/* Apply the preset row scan */
Y = i - PresetRowScan;
if (Y < 0) Y += CurrResolution.Y;
/* Loop through the pixels */
for (j = 0; j < CurrResolution.X; j++)
{
@ -1216,58 +1223,71 @@ static VOID VgaUpdateFramebuffer(VOID)
: 0);
}
/* Apply horizontal pixel panning */
if (VgaAcRegisters[VGA_AC_CONTROL_REG] & VGA_AC_CONTROL_8BIT)
{
X = j - ((VgaAcRegisters[VGA_AC_HORZ_PANNING_REG] & 0x0F) >> 1);
}
else
{
X = j - (VgaAcRegisters[VGA_AC_HORZ_PANNING_REG] & 0x0F);
}
/* Wrap around */
if (X < 0) X += CurrResolution.X;
/* Take into account DoubleVision mode when checking for pixel updates */
if (DoubleWidth && DoubleHeight)
{
/* Now check if the resulting pixel data has changed */
if (GraphicsBuffer[(i * 2 * CurrResolution.X * 2) + (j * 2)] != PixelData)
if (GraphicsBuffer[(Y * 2 * CurrResolution.X * 2) + (X * 2)] != PixelData)
{
/* Yes, write the new value */
GraphicsBuffer[(i * 2 * CurrResolution.X * 2) + (j * 2)] = PixelData;
GraphicsBuffer[(i * 2 * CurrResolution.X * 2) + (j * 2 + 1)] = PixelData;
GraphicsBuffer[((i * 2 + 1) * CurrResolution.X * 2) + (j * 2)] = PixelData;
GraphicsBuffer[((i * 2 + 1) * CurrResolution.X * 2) + (j * 2 + 1)] = PixelData;
GraphicsBuffer[(Y * 2 * CurrResolution.X * 2) + (X * 2)] = PixelData;
GraphicsBuffer[(Y * 2 * CurrResolution.X * 2) + (X * 2 + 1)] = PixelData;
GraphicsBuffer[((Y * 2 + 1) * CurrResolution.X * 2) + (X * 2)] = PixelData;
GraphicsBuffer[((Y * 2 + 1) * CurrResolution.X * 2) + (X * 2 + 1)] = PixelData;
/* Mark the specified pixel as changed */
VgaMarkForUpdate(i, j);
VgaMarkForUpdate(Y, X);
}
}
else if (DoubleWidth && !DoubleHeight)
{
/* Now check if the resulting pixel data has changed */
if (GraphicsBuffer[(i * CurrResolution.X * 2) + (j * 2)] != PixelData)
if (GraphicsBuffer[(Y * CurrResolution.X * 2) + (X * 2)] != PixelData)
{
/* Yes, write the new value */
GraphicsBuffer[(i * CurrResolution.X * 2) + (j * 2)] = PixelData;
GraphicsBuffer[(i * CurrResolution.X * 2) + (j * 2 + 1)] = PixelData;
GraphicsBuffer[(Y * CurrResolution.X * 2) + (X * 2)] = PixelData;
GraphicsBuffer[(Y * CurrResolution.X * 2) + (X * 2 + 1)] = PixelData;
/* Mark the specified pixel as changed */
VgaMarkForUpdate(i, j);
VgaMarkForUpdate(Y, X);
}
}
else if (!DoubleWidth && DoubleHeight)
{
/* Now check if the resulting pixel data has changed */
if (GraphicsBuffer[(i * 2 * CurrResolution.X) + j] != PixelData)
if (GraphicsBuffer[(Y * 2 * CurrResolution.X) + X] != PixelData)
{
/* Yes, write the new value */
GraphicsBuffer[(i * 2 * CurrResolution.X) + j] = PixelData;
GraphicsBuffer[((i * 2 + 1) * CurrResolution.X) + j] = PixelData;
GraphicsBuffer[(Y * 2 * CurrResolution.X) + X] = PixelData;
GraphicsBuffer[((Y * 2 + 1) * CurrResolution.X) + X] = PixelData;
/* Mark the specified pixel as changed */
VgaMarkForUpdate(i, j);
VgaMarkForUpdate(Y, X);
}
}
else // if (!DoubleWidth && !DoubleHeight)
{
/* Now check if the resulting pixel data has changed */
if (GraphicsBuffer[i * CurrResolution.X + j] != PixelData)
if (GraphicsBuffer[Y * CurrResolution.X + X] != PixelData)
{
/* Yes, write the new value */
GraphicsBuffer[i * CurrResolution.X + j] = PixelData;
GraphicsBuffer[Y * CurrResolution.X + X] = PixelData;
/* Mark the specified pixel as changed */
VgaMarkForUpdate(i, j);
VgaMarkForUpdate(Y, X);
}
}
}
@ -1298,6 +1318,12 @@ static VOID VgaUpdateFramebuffer(VOID)
PCHAR_CELL CharBuffer = (PCHAR_CELL)ConsoleFramebuffer;
CHAR_CELL CharInfo;
/*
* Technically, the horizontal panning and preset row count should
* affect text mode too. However, it works on pixels and not characters,
* so we can't support it currently.
*/
/* Loop through the scanlines */
for (i = 0; i < CurrResolution.Y; i++)
{