wine users - Mar 2009 - Dialog base units implementation question

Hi,

I make a new topic here because i don't know if it is a bug or a
"behaviour"

CreateDialog, MapDialogRect and many api uses the dialog box base units to
convert from dialog units to pixels.

Seeing the implementation in wine and the results that real Windows o.s. do I
think that instead of using these formulas:

pixels_x = MulDiv(dlu_x, xBaseUnit, 4);
pixels_y = MulDiv(dlu_y, yBaseUnit, 8);

i get best results converting values to floating points and then rounding the
result:

pixels_x = (int)(((double)dlu_x * (double)xBaseUnit / 4.0) + 0.5);
pixels_y = (int)(((double)dlu_y * (double)yBaseUnit / 8.0) + 0.5);

If anyone can confirm (or negate) this please inform me.

Best regards,
Mauro H. Leggieri

mxmauro wrote:
> i get best results converting values to floating points and then rounding
the result:
Integer arithmetic is always faster then float point. And it makes no sense to
convert something into float just to do 2 operations. MulDiv is specifically
made for that.