void
rot(uchar * bd, int widthd, uchar * bs, int widths, int deltax, int deltay)
{
int xs, ys;
int lvl;
for(ys = 0; ys < deltay; ++ys) {
for(xs = 0; xs < deltax; ++xs) {
lvl = getlvl(bs, xs, ys, widths);
putlvl(bd, ys, deltax - xs - 1, widthd, lvl);
}
}
}
int
getlvl(uchar * b, int x, int y, int width)
{
int i;
i = offset(x, y, width);
return((b[i] & mask[x%WDSZ]) ? 1 : 0);
}
int
offset(int x, int y, int width)
{
int wbits;
wbits = (width*WDSZ);
return((y*wbits + x)/WDSZ);
}
void
putlvl(uchar * b, int x, int y, int width, int lvl)
{
uchar *p;
p = &b[offset(x, y, width)];
if(lvl) *p |= mask[x%WDSZ];
else *p &= ~mask[x%WDSZ];
}
