reactos/win32ss/gdi/dib/dib24bppc.c
Amine Khaldi 527f2f9057 [SHELL/EXPERIMENTS]
* Create a branch for some evul shell experiments.

svn path=/branches/shell-experiments/; revision=61927
2014-02-02 19:37:27 +00:00

81 lines
1.9 KiB
C

/*
* PROJECT: Win32 subsystem
* LICENSE: See COPYING in the top level directory
* FILE: subsystems/win32/win32k/dib/dib24bppc.c
* PURPOSE: C language equivalents of asm optimised 24bpp functions
* PROGRAMMERS: Jason Filby
* Magnus Olsen
*/
#include <win32k.h>
#define NDEBUG
#include <debug.h>
VOID
DIB_24BPP_HLine(SURFOBJ *SurfObj, LONG x1, LONG x2, LONG y, ULONG c)
{
PBYTE addr = (PBYTE)SurfObj->pvScan0 + y * SurfObj->lDelta + (x1 << 1) + x1;
ULONG Count = x2 - x1;
if (Count < 8)
{
/* For small fills, don't bother doing anything fancy */
while (Count--)
{
*(PUSHORT)(addr) = c;
addr += 2;
*(addr) = c >> 16;
addr += 1;
}
}
else
{
ULONG Fill[3];
ULONG MultiCount;
/* Align to 4-byte address */
while (0 != ((ULONG_PTR) addr & 0x3))
{
*(PUSHORT)(addr) = c;
addr += 2;
*(addr) = c >> 16;
addr += 1;
Count--;
}
/* If the color we need to fill with is 0ABC, then the final mem pattern
* (note little-endianness) would be:
*
* |C.B.A|C.B.A|C.B.A|C.B.A| <- pixel borders
* |C.B.A.C|B.A.C.B|A.C.B.A| <- ULONG borders
*
* So, taking endianness into account again, we need to fill with these
* ULONGs: CABC BCAB ABCA */
c = c & 0xffffff; /* 0ABC */
Fill[0] = c | (c << 24); /* CABC */
Fill[1] = (c >> 8) | (c << 16); /* BCAB */
Fill[2] = (c << 8) | (c >> 16); /* ABCA */
MultiCount = Count / 4;
do
{
*(PULONG)addr = Fill[0];
addr += 4;
*(PULONG)addr = Fill[1];
addr += 4;
*(PULONG)addr = Fill[2];
addr += 4;
}
while (0 != --MultiCount);
Count = Count & 0x03;
while (0 != Count--)
{
*(PUSHORT)(addr) = c;
addr += 2;
*(addr) = c >> 16;
addr += 1;
}
}
}