Re: *fast* changing of LineColor?

After some suggestions from the answers of the to-quick-posted-post, i
now have the following solution:

void QGLDrawProgressiveRect(CDC* pDc, CRect& rc, COLORREF crStart,
COLORREF crEnd, bool fHorizontal) {
register ULONG nMax;
register ULONG nCnt;
double dFak;
LONG* pSlice1;
LONG* pSlice2;
LONG Slice0;

CRect rcSlice = rc;
HDC hdc = pDc->GetSafeHdc();
if (hdc == 0) return;

if (fHorizontal) {
nMax = rc.right - rc.left;
pSlice1 = &rcSlice.left;
pSlice2 = &rcSlice.right;
Slice0 = rc.left;
} else {
nMax = rc.bottom - rc.top;
pSlice1 = &rcSlice.top;
pSlice2 = &rcSlice.bottom;
Slice0 = rc.top;
}

*pSlice1 = Slice0;
*pSlice2 = Slice0;

for (nCnt = 0; nCnt < nMax; nCnt++) {
dFak = nCnt;
dFak /= nMax;
(*pSlice1)++;
::SetBkColor(hdc, ColorProgressive(crStart, crEnd, dFak));
::ExtTextOut(hdc, 0, 0, ETO_OPAQUE, &rcSlice, NULL, 0, NULL);
*pSlice2 = *pSlice1;
}
}

any ideas to make it still faster?