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svn path=/trunk/; revision=1410
This commit is contained in:
Jason Filby 2000-10-18 10:42:07 +00:00
parent 14b2a471ce
commit 201009ddd9
1 changed files with 28 additions and 0 deletions
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28
reactos/drivers/dd/vga/display/vgavideo/vgavideo.h
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@ -64,3 +64,31 @@ static unsigned char saved_GC_mask; /* 0x08 */
static unsigned char leftMask;
static int byteCounter;
static unsigned char rightMask;
static void
get_masks(int x, int w)
{
register int tmp;
leftMask = rightMask = 0;
byteCounter = w;
/* right margin */
tmp = (x+w) & 7;
if (tmp) {
byteCounter -= tmp;
rightMask = (unsigned char)(0xff00 >> tmp);
}
/* left margin */
tmp = x & 7;
if (tmp) {
byteCounter -= (8 - tmp);
leftMask = (0xff >> tmp);
}
/* too small ? */
if (byteCounter < 0) {
leftMask &= rightMask;
rightMask = 0;
byteCounter = 0;
}
byteCounter /= 8;
}