| Re: [AD] Color convertors |
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> Do you mean that windows are aligned on 4 pixels boundaries, or is it just
> the width that is a multiple of 4 pixels?
The latter (I'm lazy and 4-aligned is shorter than multiple of 4): the
current asm code requires the width of the rectangles to be a multiple of 4
pixels.
> The former will in fact speed things up (even more so on 8 byte
> boundaries),
Of course. The windowed driver already makes use of a trick to ensure that
the window (position) is always aligned on a 4-byte boundary, that is
2-pixel alignment on 15/16-bit desktops and 4-pixel alignment on 24-bit
desktop.
> The non-MMX code will sufer a slight penalty since I'll be needing an
> extra register.
Playing with the legacy 80386 registers is a very fun game ;-)
---
Eric Botcazou
ebotcazou@xxxxxxxxxx