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windows-nt/Source/XPSP1/NT/drivers/video/ms/8514a/disp/strips.c

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2020-09-26 03:20:57 -05:00
/******************************Module*Header*******************************\
* Module Name: Strips.c
*
* All the line code in this driver amounts to a big bag of dirt. Someday,
* I'm going to rewrite it all. Not today, though (sigh)...
*
* Copyright (c) 1992-1994 Microsoft Corporation
\**************************************************************************/
#include "precomp.h"
/******************************Public*Routine******************************\
* VOID vssSolidHorizontal
*
* Draws left-to-right x-major near-horizontal lines using short-stroke
* vectors. Is faster than using the radial-line routine, but only works
* when every strip is 15 pels in length or less.
*
\**************************************************************************/
VOID vssSolidHorizontal(
PDEV* ppdev,
STRIP* pStrip,
LINESTATE* pLineState)
{
LONG i, cStrips;
PLONG pStrips;
LONG xPels, xSumPels, yDir;
USHORT Cmd, ssCmd, dirDraw, dirSkip;
Cmd = DRAW | WRITE | MULTIPLE_PIXELS |
DIR_TYPE_RADIAL | LAST_PIXEL_OFF |
BUS_SIZE_16 | BYTE_SWAP;
cStrips = pStrip->cStrips;
IO_FIFO_WAIT(ppdev, 3);
IO_CUR_X(ppdev, pStrip->ptlStart.x);
IO_CUR_Y(ppdev, pStrip->ptlStart.y);
IO_CMD(ppdev, Cmd);
// Setup the drawing direction and the skip direction.
dirDraw = 0x10;
if (!(pStrip->flFlips & FL_FLIP_V))
{
yDir = 1;
dirSkip = 0xC100;
}
else
{
dirSkip = 0x4100;
yDir = -1;
}
// Output the short stroke commands.
xSumPels = 0;
pStrips = pStrip->alStrips;
for (i = 0; i < cStrips; i++)
{
xPels = *pStrips++;
xSumPels += xPels;
ssCmd = (USHORT) (dirSkip | dirDraw | xPels);
IO_FIFO_WAIT(ppdev, 4);
IO_SHORT_STROKE(ppdev, ssCmd);
}
pStrip->ptlStart.x += xSumPels;
pStrip->ptlStart.y += cStrips * yDir;
}
/******************************Public*Routine******************************\
* VOID vrlSolidHorizontal
*
* Draws left-to-right x-major near-horizontal lines using radial lines.
*
\**************************************************************************/
VOID vrlSolidHorizontal(
PDEV* ppdev,
STRIP* pStrip,
LINESTATE* pLineState)
{
LONG cStrips;
USHORT Cmd;
LONG i, yInc, x, y;
PLONG pStrips;
Cmd = DRAW_LINE | DRAW | DIR_TYPE_RADIAL |
LAST_PIXEL_OFF | MULTIPLE_PIXELS | DRAWING_DIRECTION_0 |
WRITE;
cStrips = pStrip->cStrips;
x = pStrip->ptlStart.x;
y = pStrip->ptlStart.y;
yInc = 1;
if (pStrip->flFlips & FL_FLIP_V)
yInc = -1;
pStrips = pStrip->alStrips;
for (i = 0; i < cStrips; i++)
{
IO_FIFO_WAIT(ppdev, 4);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_MAJ_AXIS_PCNT(ppdev, *pStrips);
IO_CMD(ppdev, Cmd);
x += *pStrips++;
y += yInc;
}
pStrip->ptlStart.x = x;
pStrip->ptlStart.y = y;
}
/******************************Public*Routine******************************\
* VOID vssSolidVertical
*
* Draws left-to-right y-major near-vertical lines using short-stroke
* vectors. Is faster than using the radial-line routine, but only works
* when every strip is 15 pels in length or less.
*
\**************************************************************************/
VOID vssSolidVertical(
PDEV* ppdev,
STRIP* pStrip,
LINESTATE* pLineState)
{
LONG i, cStrips;
PLONG pStrips;
LONG yPels, ySumPels, yDir;
USHORT Cmd, ssCmd, dirDraw, dirSkip;
Cmd = DRAW | WRITE | MULTIPLE_PIXELS |
DIR_TYPE_RADIAL | LAST_PIXEL_OFF |
BUS_SIZE_16 | BYTE_SWAP;
cStrips = pStrip->cStrips;
IO_FIFO_WAIT(ppdev, 3);
IO_CUR_X(ppdev, pStrip->ptlStart.x);
IO_CUR_Y(ppdev, pStrip->ptlStart.y);
IO_CMD(ppdev, Cmd);
// Setup the drawing direction and the skip direction.
if (!(pStrip->flFlips & FL_FLIP_V))
{
yDir = 1;
dirDraw = 0xD0;
}
else
{
yDir = -1;
dirDraw = 0x50;
}
dirSkip = 0x0100;
// Output the short stroke commands.
ySumPels = 0;
pStrips = pStrip->alStrips;
for (i = 0; i < cStrips; i++)
{
yPels = *pStrips++;
ySumPels += yPels;
ssCmd = (USHORT) (dirSkip | dirDraw | yPels);
IO_FIFO_WAIT(ppdev, 4);
IO_SHORT_STROKE(ppdev, ssCmd);
}
pStrip->ptlStart.x += cStrips;
pStrip->ptlStart.y += ySumPels * yDir;
}
/******************************Public*Routine******************************\
* VOID vrlSolidVertical
*
* Draws left-to-right y-major near-vertical lines using radial lines.
*
\**************************************************************************/
VOID vrlSolidVertical(
PDEV* ppdev,
STRIP* pStrip,
LINESTATE* pLineState)
{
LONG cStrips;
USHORT Cmd;
LONG i, x, y;
PLONG pStrips;
cStrips = pStrip->cStrips;
pStrips = pStrip->alStrips;
x = pStrip->ptlStart.x;
y = pStrip->ptlStart.y;
if (!(pStrip->flFlips & FL_FLIP_V))
{
Cmd = DRAW_LINE | DRAW | DIR_TYPE_RADIAL |
LAST_PIXEL_OFF | MULTIPLE_PIXELS | DRAWING_DIRECTION_270 |
WRITE;
for (i = 0; i < cStrips; i++)
{
IO_FIFO_WAIT(ppdev, 4);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_MAJ_AXIS_PCNT(ppdev, *pStrips);
IO_CMD(ppdev, Cmd);
y += *pStrips++;
x++;
}
}
else
{
Cmd = DRAW_LINE | DRAW | DIR_TYPE_RADIAL |
LAST_PIXEL_OFF | MULTIPLE_PIXELS | DRAWING_DIRECTION_90 |
WRITE;
for (i = 0; i < cStrips; i++)
{
IO_FIFO_WAIT(ppdev, 4);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_MAJ_AXIS_PCNT(ppdev, *pStrips);
IO_CMD(ppdev, Cmd);
y -= *pStrips++;
x++;
}
}
pStrip->ptlStart.x = x;
pStrip->ptlStart.y = y;
}
/******************************Public*Routine******************************\
* VOID vssSolidDiagonalHorizontal
*
* Draws left-to-right x-major near-diagonal lines using short-stroke
* vectors. Is faster than using the radial-line routine, but only
* works when every strip is 15 pels in length or less.
*
\**************************************************************************/
VOID vssSolidDiagonalHorizontal(
PDEV* ppdev,
STRIP* pStrip,
LINESTATE* pLineState)
{
LONG i, cStrips;
PLONG pStrips;
LONG Pels, SumPels, yDir;
USHORT Cmd, ssCmd, dirDraw, dirSkip;
Cmd = DRAW | WRITE | MULTIPLE_PIXELS |
DIR_TYPE_RADIAL | LAST_PIXEL_OFF |
BUS_SIZE_16 | BYTE_SWAP;
cStrips = pStrip->cStrips;
IO_FIFO_WAIT(ppdev, 3);
IO_CUR_X(ppdev, pStrip->ptlStart.x);
IO_CUR_Y(ppdev, pStrip->ptlStart.y);
IO_CMD(ppdev, Cmd);
// Setup the drawing direction and the skip direction.
if (!(pStrip->flFlips & FL_FLIP_V))
{
yDir = 1;
dirDraw = 0xF0;
dirSkip = 0x4100;
}
else
{
yDir = -1;
dirDraw = 0x30;
dirSkip = 0xC100;
}
// Output the short stroke commands.
SumPels = 0;
pStrips = pStrip->alStrips;
for (i = 0; i < cStrips; i++)
{
Pels = *pStrips++;
SumPels += Pels;
ssCmd = (USHORT)(dirSkip | dirDraw | Pels);
IO_FIFO_WAIT(ppdev, 4);
IO_SHORT_STROKE(ppdev, ssCmd);
}
pStrip->ptlStart.x += SumPels;
pStrip->ptlStart.y += (SumPels - cStrips) * yDir;
}
/******************************Public*Routine******************************\
* VOID vrlSolidDiagonalHorizontal
*
* Draws left-to-right x-major near-diagonal lines using radial lines.
*
\**************************************************************************/
VOID vrlSolidDiagonalHorizontal(
PDEV* ppdev,
STRIP* pStrip,
LINESTATE* pLineState)
{
LONG cStrips;
USHORT Cmd;
LONG i, x, y;
PLONG pStrips;
cStrips = pStrip->cStrips;
pStrips = pStrip->alStrips;
x = pStrip->ptlStart.x;
y = pStrip->ptlStart.y;
if (!(pStrip->flFlips & FL_FLIP_V))
{
Cmd = DRAW_LINE | DRAW | DIR_TYPE_RADIAL |
LAST_PIXEL_OFF | MULTIPLE_PIXELS | DRAWING_DIRECTION_315 |
WRITE;
for (i = 0; i < cStrips; i++)
{
IO_FIFO_WAIT(ppdev, 4);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_MAJ_AXIS_PCNT(ppdev, *pStrips);
IO_CMD(ppdev, Cmd);
y += *pStrips - 1;
x += *pStrips++;
}
}
else
{
Cmd = DRAW_LINE | DRAW | DIR_TYPE_RADIAL |
LAST_PIXEL_OFF | MULTIPLE_PIXELS | DRAWING_DIRECTION_45 |
WRITE;
for (i = 0; i < cStrips; i++)
{
IO_FIFO_WAIT(ppdev, 4);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_MAJ_AXIS_PCNT(ppdev, *pStrips);
IO_CMD(ppdev, Cmd);
y -= *pStrips - 1;
x += *pStrips++;
}
}
pStrip->ptlStart.x = x;
pStrip->ptlStart.y = y;
}
/******************************Public*Routine******************************\
* VOID vssSolidDiagonalVertical
*
* Draws left-to-right y-major near-diagonal lines using short-stroke
* vectors. Is faster than using the radial-line routine, but only
* works when every strip is 15 pels in length or less.
*
\**************************************************************************/
VOID vssSolidDiagonalVertical(
PDEV* ppdev,
STRIP* pStrip,
LINESTATE* pLineState)
{
LONG i, cStrips;
PLONG pStrips;
LONG Pels, SumPels, yDir;
USHORT Cmd, ssCmd, dirDraw, dirSkip;
Cmd = DRAW | WRITE | MULTIPLE_PIXELS |
DIR_TYPE_RADIAL | LAST_PIXEL_OFF |
BUS_SIZE_16 | BYTE_SWAP;
cStrips = pStrip->cStrips;
IO_FIFO_WAIT(ppdev, 3);
IO_CUR_X(ppdev, pStrip->ptlStart.x);
IO_CUR_Y(ppdev, pStrip->ptlStart.y);
IO_CMD(ppdev, Cmd);
// Setup the drawing direction and the skip direction.
if (!(pStrip->flFlips & FL_FLIP_V))
{
yDir = 1;
dirDraw = 0xF0;
}
else
{
yDir = -1;
dirDraw = 0x30;
}
dirSkip = 0x8100;
// Output the short stroke commands.
SumPels = 0;
pStrips = pStrip->alStrips;
for (i = 0; i < cStrips; i++)
{
Pels = *pStrips++;
SumPels += Pels;
ssCmd = (USHORT)(dirSkip | dirDraw | Pels);
IO_FIFO_WAIT(ppdev, 4);
IO_SHORT_STROKE(ppdev, ssCmd);
}
pStrip->ptlStart.x += SumPels - cStrips;
pStrip->ptlStart.y += SumPels * yDir;
}
/******************************Public*Routine******************************\
* VOID vrlSolidDiagonalVertical
*
* Draws left-to-right y-major near-diagonal lines using radial lines.
*
\**************************************************************************/
VOID vrlSolidDiagonalVertical(
PDEV* ppdev,
STRIP* pStrip,
LINESTATE* pLineState)
{
LONG cStrips;
USHORT Cmd;
LONG i, x, y;
PLONG pStrips;
cStrips = pStrip->cStrips;
pStrips = pStrip->alStrips;
x = pStrip->ptlStart.x;
y = pStrip->ptlStart.y;
if (!(pStrip->flFlips & FL_FLIP_V))
{
Cmd = DRAW_LINE | DRAW | DIR_TYPE_RADIAL |
LAST_PIXEL_OFF | MULTIPLE_PIXELS | DRAWING_DIRECTION_315 |
WRITE;
for (i = 0; i < cStrips; i++)
{
IO_FIFO_WAIT(ppdev, 4);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_MAJ_AXIS_PCNT(ppdev, *pStrips);
IO_CMD(ppdev, Cmd);
y += *pStrips;
x += *pStrips++ - 1;
}
}
else
{
Cmd = DRAW_LINE | DRAW | DIR_TYPE_RADIAL |
LAST_PIXEL_OFF | MULTIPLE_PIXELS | DRAWING_DIRECTION_45 |
WRITE;
for (i = 0; i < cStrips; i++)
{
IO_FIFO_WAIT(ppdev, 4);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_MAJ_AXIS_PCNT(ppdev, *pStrips);
IO_CMD(ppdev, Cmd);
y -= *pStrips;
x += *pStrips++ - 1;
}
}
pStrip->ptlStart.x = x;
pStrip->ptlStart.y = y;
}
/******************************Public*Routine******************************\
* VOID vStripStyledHorizontal
*
* Takes the list of strips that define the pixels that would be lit for
* a solid line, and breaks them into styling chunks according to the
* styling information that is passed in.
*
* This particular routine handles x-major lines that run left-to-right,
* and are comprised of horizontal strips. It draws the dashes using
* short-stroke vectors.
*
* The performance of this routine could be improved significantly if
* anyone cared enough about styled lines improve it.
*
\**************************************************************************/
VOID vStripStyledHorizontal(
PDEV* ppdev,
STRIP* pstrip,
LINESTATE* pls)
{
LONG x;
LONG y;
ULONG dirSkip;
LONG dy;
LONG* plStrip;
LONG cStrips;
LONG cStyle;
LONG cStrip;
LONG cThis;
ULONG bIsGap;
if (pstrip->flFlips & FL_FLIP_V)
{
// The minor direction of the line is 90 degrees, and the major
// direction is 0 (it's a left-to-right x-major line going up):
dirSkip = 0x4110;
dy = -1;
}
else
{
// The minor direction of the line is 270 degrees, and the major
// direction is 0 (it's a left-to-right x-major line going down):
dirSkip = 0xc110;
dy = 1;
}
cStrips = pstrip->cStrips; // Total number of strips we'll do
plStrip = pstrip->alStrips; // Points to current strip
x = pstrip->ptlStart.x; // x position of start of first strip
y = pstrip->ptlStart.y; // y position of start of first strip
// Warm up the hardware so that it will know we'll be outputing
// short-stroke vectors, and so that it will have the current position
// correctly set if we're starting in the middle of a 'dash':
IO_FIFO_WAIT(ppdev, 3);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_CMD(ppdev, DRAW | WRITE | MULTIPLE_PIXELS |
DIR_TYPE_RADIAL | LAST_PIXEL_OFF | BUS_SIZE_16 |
BYTE_SWAP);
cStrip = *plStrip; // Number of pels in first strip
cStyle = pls->spRemaining; // Number of pels in first 'gap' or 'dash'
bIsGap = pls->ulStyleMask; // Tells whether in a 'gap' or a 'dash'
// ulStyleMask is non-zero if we're in the middle of a 'gap',
// and zero if we're in the middle of a 'dash':
if (bIsGap)
goto SkipAGap;
else
goto OutputADash;
PrepareToSkipAGap:
// Advance in the style-state array, so that we can find the next
// 'dot' that we'll have to display:
bIsGap = ~bIsGap;
pls->psp++;
if (pls->psp > pls->pspEnd)
pls->psp = pls->pspStart;
cStyle = *pls->psp;
// If 'cStrip' is zero, we also need a new strip:
if (cStrip != 0)
goto SkipAGap;
// Here, we're in the middle of a 'gap' where we don't have to
// display anything. We simply cycle through all the strips
// we can, keeping track of the current position, until we run
// out of 'gap':
while (TRUE)
{
// Each time we loop, we move to a new scan and need a new strip:
y += dy;
plStrip++;
cStrips--;
if (cStrips == 0)
goto AllDone;
cStrip = *plStrip;
SkipAGap:
cThis = min(cStrip, cStyle);
cStyle -= cThis;
cStrip -= cThis;
x += cThis;
if (cStyle == 0)
goto PrepareToOutputADash;
}
PrepareToOutputADash:
// Advance in the style-state array, so that we can find the next
// 'dot' that we'll have to display:
bIsGap = ~bIsGap;
pls->psp++;
if (pls->psp > pls->pspEnd)
pls->psp = pls->pspStart;
cStyle = *pls->psp;
// We're gonna need the current position to be correct when we
// start outputing short-stroke vectors:
IO_FIFO_WAIT(ppdev, 2);
IO_CUR_X(ppdev, x);
// If 'cStrip' is zero, we also need a new strip.
if (cStrip != 0)
{
// There's more to be done in the current strip, so set 'y'
// to be the current scan:
IO_CUR_Y(ppdev, y);
goto OutputADash;
}
// Set 'y' to be the scan we're about to move to, because we've
// finished with the current strip:
IO_CUR_Y(ppdev, y + dy);
while (TRUE)
{
// Each time we loop, we move to a new scan and need a new strip:
y += dy;
plStrip++;
cStrips--;
if (cStrips == 0)
goto AllDone;
cStrip = *plStrip;
OutputADash:
cThis = min(cStrip, cStyle);
cStyle -= cThis;
cStrip -= cThis;
x += cThis;
// Short stroke vectors can handle lines that are a maximum of
// 15 pels long. When we have to draw a longer consecutive
// segment than that, we simply break it into 16 pel portions:
while (cThis > 15)
{
// Draw two horizontal strokes together to make up one 16 pel
// segment:
IO_FIFO_WAIT(ppdev, 1);
IO_SHORT_STROKE(ppdev, 0x1f11);
cThis -= 16;
}
// Draw the remaining lit part of the strip:
IO_FIFO_WAIT(ppdev, 1);
IO_SHORT_STROKE(ppdev, dirSkip | cThis);
if (cStyle == 0)
goto PrepareToSkipAGap;
}
AllDone:
// Update our state variables so that the next line can continue
// where we left off:
pls->spRemaining = cStyle;
pls->ulStyleMask = bIsGap;
pstrip->ptlStart.x = x;
pstrip->ptlStart.y = y;
}
/******************************Public*Routine******************************\
* VOID vStripStyledVertical
*
* Takes the list of strips that define the pixels that would be lit for
* a solid line, and breaks them into styling chunks according to the
* styling information that is passed in.
*
* This particular routine handles y-major lines that run left-to-right,
* and are comprised of vertical strips. It draws the dashes using
* short-stroke vectors.
*
* The performance of this routine could be improved significantly if
* anyone cared enough about styled lines improve it.
*
\**************************************************************************/
VOID vStripStyledVertical(
PDEV* ppdev,
STRIP* pstrip,
LINESTATE* pls)
{
LONG x;
LONG y;
ULONG dirSkip;
ULONG dirSkip16;
LONG dy;
LONG* plStrip;
LONG cStrips;
LONG cStyle;
LONG cStrip;
LONG cThis;
ULONG bIsGap;
if (pstrip->flFlips & FL_FLIP_V)
{
// The minor direction of the line is 0 degrees, and the major
// direction is 90 (it's a left-to-right y-major line going up):
dirSkip = 0x0150;
dirSkip16 = 0x5f51; // For drawing 16 pels straight up
dy = -1;
}
else
{
// The minor direction of the line is 0 degrees, and the major
// direction is 270 (it's a left-to-right y-major line going down):
dirSkip = 0x01d0;
dirSkip16 = 0xdfd1; // For drawing 16 pels straight down
dy = 1;
}
cStrips = pstrip->cStrips; // Total number of strips we'll do
plStrip = pstrip->alStrips; // Points to current strip
x = pstrip->ptlStart.x; // x position of start of first strip
y = pstrip->ptlStart.y; // y position of start of first strip
// Warm up the hardware so that it will know we'll be outputing
// short-stroke vectors, and so that it will have the current position
// correctly set if we're starting in the middle of a 'dash':
IO_FIFO_WAIT(ppdev, 3);
IO_CUR_X(ppdev, x);
IO_CUR_Y(ppdev, y);
IO_CMD(ppdev, DRAW | WRITE | MULTIPLE_PIXELS |
DIR_TYPE_RADIAL | LAST_PIXEL_OFF | BUS_SIZE_16 |
BYTE_SWAP);
cStrip = *plStrip; // Number of pels in first strip
cStyle = pls->spRemaining; // Number of pels in first 'gap' or 'dash'
bIsGap = pls->ulStyleMask; // Tells whether in a 'gap' or a 'dash'
// ulStyleMask is non-zero if we're in the middle of a 'gap',
// and zero if we're in the middle of a 'dash':
if (bIsGap)
goto SkipAGap;
else
goto OutputADash;
PrepareToSkipAGap:
// Advance in the style-state array, so that we can find the next
// 'dot' that we'll have to display:
bIsGap = ~bIsGap;
pls->psp++;
if (pls->psp > pls->pspEnd)
pls->psp = pls->pspStart;
cStyle = *pls->psp;
// If 'cStrip' is zero, we also need a new strip:
if (cStrip != 0)
goto SkipAGap;
// Here, we're in the middle of a 'gap' where we don't have to
// display anything. We simply cycle through all the strips
// we can, keeping track of the current position, until we run
// out of 'gap':
while (TRUE)
{
// Each time we loop, we move to a new column and need a new strip:
x++;
plStrip++;
cStrips--;
if (cStrips == 0)
goto AllDone;
cStrip = *plStrip;
SkipAGap:
cThis = min(cStrip, cStyle);
cStyle -= cThis;
cStrip -= cThis;
y += (dy > 0) ? cThis : -cThis;
if (cStyle == 0)
goto PrepareToOutputADash;
}
PrepareToOutputADash:
// Advance in the style-state array, so that we can find the next
// 'dot' that we'll have to display:
bIsGap = ~bIsGap;
pls->psp++;
if (pls->psp > pls->pspEnd)
pls->psp = pls->pspStart;
cStyle = *pls->psp;
// We're gonna need the current position to be correct when we
// start outputing short-stroke vectors:
IO_FIFO_WAIT(ppdev, 2);
IO_CUR_Y(ppdev, y);
// If 'cStrip' is zero, we also need a new strip.
if (cStrip != 0)
{
// There's more to be done in the current strip, so set 'x'
// to be the current column:
IO_CUR_X(ppdev, x);
goto OutputADash;
}
// Set 'x' to be the column we're about to move to, because we've
// finished with the current strip:
IO_CUR_X(ppdev, x + 1);
while (TRUE)
{
// Each time we loop, we move to a new column and need a new strip:
x++;
plStrip++;
cStrips--;
if (cStrips == 0)
goto AllDone;
cStrip = *plStrip;
OutputADash:
cThis = min(cStrip, cStyle);
cStyle -= cThis;
cStrip -= cThis;
y += (dy > 0) ? cThis : -cThis;
// Short stroke vectors can handle lines that are a maximum of
// 15 pels long. When we have to draw a longer consecutive
// segment than that, we simply break it into 16 pel portions:
while (cThis > 15)
{
// Draw two vertical strokes together to make up one 16 pel
// segment:
IO_FIFO_WAIT(ppdev, 1);
IO_SHORT_STROKE(ppdev, dirSkip16);
cThis -= 16;
}
// Draw the remaining lit part of the strip:
IO_FIFO_WAIT(ppdev, 1);
IO_SHORT_STROKE(ppdev, dirSkip | cThis);
if (cStyle == 0)
goto PrepareToSkipAGap;
}
AllDone:
// Update our state variables so that the next line can continue
// where we left off:
pls->spRemaining = cStyle;
pls->ulStyleMask = bIsGap;
pstrip->ptlStart.x = x;
pstrip->ptlStart.y = y;
}
Reference in a new issue Copy permalink